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Scots pine (Pinus sylvestris L.) seeds have variable levels of primary dormancy which reflect within-species adaptation to local environments. The objective of this study was to use a thermal time approach to determine whether primary dormancy levels in seeds were correlated with mean ambient temperature during temperature-sensitive phases of the reproductive cycle. Seedlots were obtained from a single open-pollinated clonal seed orchard in five crop years and germinated over a wide temperature range (7–35 °C) to calculate base temperature for germination with and without pre-chills (4 and 8 weeks). Primary dormancy levels varied amongst seedlots collected in different crop years (CY). Unchilled seeds were the most dormant for CY2007 (Tb = 10.9 °C) and least dormant for CY2012 (Tb = 5.6 °C). Base temperatures for germination were correlated with mean ambient temperature during different phases of the reproductive cycle. There was a strong positive correlation between base temperature for germination of unchilled seeds and mean temperature during pollination and early pollen tube growth. This suggests that maternal environmental effects during this phase could potentially select for dormant or non-dormant seeds, which has implications for tree breeding and seedling production in forest nurseries.

In multisite forest genetic experiments, the presence of genotype × environment interaction (GEI) is common. GEI may negatively affect the estimates of genetic variance and hamper selection decisions in tree breeding programs. Several measures exist to evaluate the stability of tested genotypes’ performance across environments with a choice of the method likely affecting breeders’ decisions. In this study, we evaluated variation in diameter and height growth performance in the progeny test established at 4 sites with 80 open-pollinated half-sib families of Scots pine. We found significant variation among examined progeny at age 10, reaching up to 31% for diameter and 20% for height depending on site, and significant GEI in both traits. We estimated contribution of each family to GEI using various methods and tools of GEI analysis—AMMI, GGE biplots, heterogeneity of regression coefficients (bi’s), the deviation mean squares from regression (s2di) and Kang’s yield-stability index (YSi). Despite the presence of the cross-over interaction, family ranks did not vary much among sites. The selections based on the phenotype, YSi and restricted bi corresponded well to each other leading to the expected response to selection up to 7.8% on diameter and 4.4% on height, whereas those based on the AMMI stability variance were different and lead to a slight loss in both traits. We discuss our results in the context of the usefulness of those measures of genotype stability for tree breeding programs and propose the procedure to follow for making selection decisions in forest experiments with GEI.

The study of vegetative phenology is important to understand adaptation to different environments and potential trade-offs with growth traits. Crown leaf-out and leaf-fall phenology was evaluated on 168 open-pollinated families from 19 Cedrela odorata provenances in an eleven-year-old provenance/progeny trial established in the state of Veracruz, Eastern coast of Mexico. The objectives were: (a) to evaluate the extent of inter- and intra-population genetic variation of leaf phenology traits; (b) to examine the relationship between leaf phenology traits and climate variables at the population level; (c) to estimate the genetic relationships between leaf phenology and growth traits; and (d) to evaluate the accuracy, in terms of genetic control, of using alternative methods to measure leaf phenology in broadleaf trees. The study revealed significant genetic variation in leaf phenology traits both among and within populations. Leaf-out traits showed higher genetic variation than leaf-fall traits. A moderate to large genetic differentiation among Cedrela odorata populations was found; Qst values for leaf-out were 2–6 times higher than those for leaf-fall. Leaf-fall was primarily associated with mean annual temperature, while leaf-out and length of the leafless period were related to annual precipitation and the aridity index of the site of origin. Leaf phenology traits showed moderate to high genetic control (h2i = 0.12–0.67; h2f = 0.27–0.72). However, it was higher for leaf-out traits, so they might play a more important adaptive role. Genetic correlations between leaf phenology and growth traits allow selecting early flushing genotypes within populations to increase adaptation and growth, but caution should be taken when selecting among populations.

Tolitoli District has a potential for agarwood trees in the forests, but it has not been optimally utilized and preserved by the local communities. Therefore, efforts are needed to increase understanding and community involvement in cultivation and product development of agarwood trees. The objectives of this activity are: to explore agarwood tree species in the forest and sources of local inoculums using a purposive sampling method for agarwood production, to assess the suitability of agro-climates for agarwood tree cultivation, to conduct face-to-face training and practice for agarwood tree breeding and bio-induction by injection, and to identify socio-economic conditions to support agarwood tree cultivation for community empowerment through product development and cultivation in Kabupaten Tolitoli. The project was implementated by exploring and identifying the existence of natural agarwood trees and agarwood farmers, training, and mentoring. The results of exploration and identification showed that Kabupaten Tolitoli has natural resources of agarwood trees in the forest and local inoculums for the bio-induction of agarwood formation. Also, the local community, including the local government, practitioners, farmers, and educational institutions, have great interest and desire for product development and cultivation of agarwood trees. Thus, it can be concluded that community empowerment through product development and cultivation of agarwood trees in Kabupaten Tolitoli can be implemented.

Made available in DSpace on 2021-06-25T10:20:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The survival, initial productivity, and the genetic parameters of Corymbia citriodora subsp. citriodora (CCC), Corymbia citriodora subsp. variegata (CCV), and Corymbia torelliana (CT) were used to develop a breeding strategy for the Corymbia species. Survival, height, and diameter at breast height (DBH) data were assessed 24 and 36 months after planting, and the mean annual volume increment was estimated in three trials. Longitudinal DBH data analysis was applied individually to each trial to identify the best and the poorest families at both ages. The mortality ranged from 5% in CT to 27% in CCC, and the mean annual increment varied from 17.8 to 20 m3·ha 1·year 1 at 36 months after planting. The 36-month narrow-sense heritability (h2a) was high for CCV (0.69 6 0.17), moderate for CCC (0.41 6 0.11), and low for CT (0.21 6 0.09). The genetic parameters indicated the need for different breeding strategies for each species. Selecting the best families while roguing the poor families allowed forward selection of CCC and CCV. It was possible to select good CT trees for hybrid breeding; however, improving the species population requires focusing on increasing the effective size and expanding the genetic variability in the CT population. São Paulo State University (Unesp) School of Agricultural and Veterinary Sciences, Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, Km 5 Forest Industries Research Centre University of the Sunshine Coast, Maroochydore DC Midwestern State University (UNICENTRO) Sector of Agricultural and Environmental Sciences (SEAA/I), Rua Professora Maria Roza Zanon de Almeida Engenheiro-Gutierrez Forest Science and Research Institute (IPEF), Via Comendador Pedro Morganti, 3500 Bairro Monte Alegre São Paulo State University (Unesp) School of Agricultural and Veterinary Sciences, Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, Km 5

Tree breeding has focused on increasing stem volume growth with a cost to fecundity. However, fecundity is important in maintaining the fitness in natural stands and facilitating cross‐pollination to advance breeding populations. Understanding the inheritance of fecundity and the genetic relationship between fecundity and growth is essential to understand the constraints of evolution in natural population and design an optimal selection strategy to balance breeding for growth and fecundity. Inheritance of female fecundity and the genetic relationship between fecundity and growth in radiata pine were investigated using a large Australia‐wide progeny test, planted on eight sites involving 279 control‐pollinated families. It was found that fecundity of female cones was highly heritable with an estimated heritability of 0.39–0.61, but genetically correlated with growth (−0.30 to −0.39). This indicates that improvement in tree growth alone could reduce the fecundity, thus to break the possible evolutionary constraint in natural population. To maintain fecundity for breeding purposes and minimize the interruption of the evolutionary constraint between fecundity and growth, use of a restraint selection index to impose no change of fecundity is developed in current breeding, while dissecting the genetic basis of adversely correlated traits at loci level is required for optimal long‐term strategy.

With climate change, the pressure on tree breeding to provide varieties with improved resilience to biotic and abiotic stress is increasing. As such, pest resistance is of high priority but has been neglected in most tree breeding programs, given the complexity of phenotyping for these traits and delays to assess mature trees. In addition, the existing genetic variation of resistance and its relationship with productivity should be better understood for their consideration in multitrait breeding. In this study, we evaluated the prospects for genetic improvement of the levels of acetophenone aglycones (AAs) in white spruce needles, which have been shown to be tightly linked to resistance to spruce budworm. Furthermore, we estimated the accuracy of genomic selection (GS) for these traits, allowing selection at a very early stage to accelerate breeding. A total of 1,516 progeny trees established on five sites and belonging to 136 full‐sib families from a mature breeding population in New Brunswick were measured for height growth and genotyped for 4,148 high‐quality SNPs belonging to as many genes along the white spruce genome. In addition, 598 trees were assessed for levels of AAs piceol and pungenol in needles, and 578 for wood stiffness. GS models were developed with the phenotyped trees and then applied to predict the trait values of unphenotyped trees. AAs were under moderate‐to‐high genetic control (h 2: 0.43–0.57) with null or marginally negative genetic correlations with other traits. The prediction accuracy of GS models (GBLUP) for AAs was high (PAAC: 0.63–0.67) and comparable or slightly higher than pedigree‐based (ABLUP) or BayesCπ models. We show that AA traits can be improved and that GS speeds up the selection of improved trees for insect resistance and for growth and wood quality traits. Various selection strategies were tested to optimize multitrait gains.

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook), a fast-growing and economically important timber tree species in China, is widely used in construction, furniture, and paper manufacture but has a long breeding cycle. Chemical mutagens, such as ethyl methane sulfonate (EMS) and sodium azide (SA), are widely used in crops such as rice, wheat, cotton, soybean and sugarcane but their utility for tree breeding is unknown. In this study we examined the effects of EMS and SA on Chinese fir seed germination and growth. Chinese fir seeds were treated with the two chemical mutagens; were planted in Jiangle County, Fujian Province, China; and their heights were measured from 2011 to 2017. The concentrations and durations of treatment with the two chemical mutagens were significantly associated with the Chinese fir seedling and mortality rates, as well as with the heights of trees from the seedling stage to 3 years old. We also generated 127 mutants with abnormal branches and reproductive growth. We report here the effects of two chemical mutagens on Chinese fir breeding; our data will contribute to knowledge of the utility of EMS and SA in forestry.

Sandalwood (Santalum austrocaledonicum) is a fragrant tree of cultural and commercial importance in Vanuatu. The trade in its wild products has long provided income to landowners on remote islands....

Santalum yasi is a high-value hemiparasitic tree endemic to Fiji, Niue and Tonga. It has been overexploited for its oil-yielding heartwood and is now threatened. Remaining stands lack genetic diver...

Introduction Representatives of the genus Fagus are mainly forest-forming species of first storey of stands. European beech (Fagus sylvatica L.) outside its natural range is used to plant forest stands, mainly in western regions of Ukraine. On the right bank of the Dnipro, it forms productive stands (Korinko 2007, Belous 1962, Kokhno & Parkhomenko 2002). Despite the fact that the Left-Bank part of Ukraine has a more continental climate compared to the climate in the natural range of beech, the results of the European and Crimean (Fagus taurica Popl.) beeches introduction were positive in most of the cases (Ihnatenko et al. 2006, Los et al. 2014). According to previous studies, European and Crimean beeches in the northern Left-Bank Forest-Steppe have mainly high adaptive properties and are characterized by sufficiently high quantitative and qualitative indicators (Los et al. 2014, 2018). Thus, the introduction of these species can be considered relatively successful. The aim of the study was to determine how promising the species of the genus Fagus are for the plantations of different purposes in the northeast of Ukraine based on a complex assessment of the growth and development of Fagus trees in the experimental plantations and arboretums. Materials and Methods The article represents generalized results of the research of beech in arboretums and experimental plantations in the northeast of Ukraine, mainly in fresh fertile sites, on dark grey forest soil of loamy mechanical composition. The study has been carried out in recent years, in accordance with generally accepted forest mensuration and tree breeding methods, as well as by an improved methodology for a complex assessment of promising non-native tree species. Results In most of the plots (6 out of 9) the trees of different beech species were in good and satisfactory conditions, mass damage by pests or diseases had not been detected. The 56-year-old trees in the experimental plantation in Trostianets Forest Enterprise of Sumy Region had the highest growth intensity. The average annual growth by height was from 0.48 to 0.62 m there, and by diameter – from 0.48 to 0.66 cm. The part of trees of I and II selection categories were 23.1–24.0%. The studied plantations in Kharkiv Region had worse growth rates. A high proportion of multitrunk trees (50–79%) was observed in provenance test in the Kharkiv Forest Research Station. Comparison of the average heights and diameters of European beech climatypes in provenance test in Kharkiv Region (Ukrainian Research Institute of Forestry and Forest Melioration) showed the advantages of the variant originating from the Shchyrets district (Transcarpathia). A trunk volume of an average tree of this climatype at the age of 48 was twice as large as the other variants had and almost the same as that of the common oak. The growth intensity indicators of Crimean beech were similar to those of European beech. The increase in the height of Eastern beech in the arboretum of Kharkiv National Agrarian University was similar to that of forest beech at other sites in Kharkiv Region, but Eastern beech was characterized by the largest increase in diameter (0.7 cm/year). Regular fruiting and self-seeding of European and Crimean beeches were noted in both the experimental plantations and arboretums of Trostianets Forest Enterprise, Ukrainian Research Institute of Forestry and Forest Melioration and Kharkiv National Agrarian University. Most of the observed stands have been assessed as 4 or 5 degrees of acclimatization according to the scale of O. Lypa. The total score of the complex assessment of most beech objects on six indicators was from 13 to 28. The results of the assessment of two forest beech plantations (experimental crops and a site in the arboretum of Trostianets Forest Enterprise) showed that the species is promising for its usage in forestry. The findings indicate not only a high adaptive capacity of the genus Fagus species when being introduced, they also point at their high plasticity. Therefore, we can assume that these species are able to tolerate an increase in the climate’s continentally in their natural areas with no significant loss in productivity. However, this suggestion requires a further study. Conclusions European beech in the experimental plantations of Trostianets Forest Enterprise in Sumy Region showed better growth intensity and trunk quality compared to other studied Fagus trees there, so to English oak of a local origin (height was 13.5% higher, diameter was 6.4% higher). Growth intensity rates of Crimean beech were similar to those of European beech. In other plots of the experimental plantations and in arboretums, beech was characterized by growth indices equal or below the yield table level of English oak. In most of the observed stands regular fruiting and self-seeding were noted. According to the results of the complex assessment, both European and Crimean beeches are recommended to use when establishing forest plantations in the Forest-Steppe part of Sumy Region, as well as in landscaping in Kharkiv and Sumy Regions. 9 Figs., 3 Tables, 23 Refs. Key words: Fagus, complex assessment, multitrunk, selection category, reproduction.

It is important to improve the understanding of the interactions between the trees and pathogens and integrate this knowledge about disease resistance into tree breeding programs. The conifer Norway spruce (Picea abies) is an important species for the forest industry in Europe. Its major pathogen is Heterobasidion parviporum, causing stem and root rot. In this study, we identified 11 Norway spruce QTLs (Quantitative trait loci) that correlate with variation in resistance to H. parviporum in a population of 466 trees by association genetics. Individual QTLs explained between 2.1 and 5.2% of the phenotypic variance. The expression of candidate genes associated with the QTLs was analysed in silico and in response to H. parviporum hypothesizing that (a) candidate genes linked to control of fungal sapwood growth are more commonly expressed in sapwood, and; (b) candidate genes associated with induced defences are respond to H. parviporum inoculation. The Norway spruce laccase PaLAC5 associated with control of lesion length development is likely to be involved in the induced defences. Expression analyses showed that PaLAC5 responds specifically and strongly in close proximity to the H. parviporum inoculation. Thus, PaLAC5 may be associated with the lignosuberized boundary zone formation in bark adjacent to the inoculation site.

Introduction Austrian pine is naturally distributed in the Central Europe mountains, where it forms resistant stands at an altitude of 250–1,800 m. Due to environmental plasticity, Black pine is one of the most common species in forest regeneration worldwide. Thanks to its high ornamentality and resistance to air pollution, this species is widespread in parks and urban and industrial areas. The species was introduced into Ukraine about 200 years ago. Dobrovolsky recommended using it on richer types of sandy soils and sandy loams, transitional to clay-loams, for marginal pine forests with a small admixture of deciduous trees and shade-tolerant shrubs. The aim of the work was to characterize the Austrian pine stands of various ages of the first and second generations in Kirovohrad, Kharkiv and Sumy Regions and conduct a comprehensive assessment of their productivity, trunk quality and condition. Materials and methods Five Austrian pine stands were observed in Kirovohrad, Kharkiv and Sumy Regions during 2017–2018. The stands assessment was carried out based on the average height and diameter, an average tree volume, selection category, health category and reproduction. Mensuration variables were determined by generally accepted methods; both the selection category and the health category were defined according to the classification developed by the Laboratory of Forest Tree Breeding of URIFFM. Furthermore, the variability level of the growth indices was determined based on S. S. Mamayev scale. Growth rates of Austrian pine and Sсotсh pine were compared by means of Student's test. Prospective viability of Austrian pine was determined according to a 3-point scale. Results In the State Enterprise “Oleksandrivske Forest Economy” in Kirovohrad Region in the fresh fairly infertile site, Austrian pine and Sсots pine grow according to the II productivity class. Austrian pine at the age of 117 reached the height of 26.5 m which was 6.4% shorter than the Scots pine. Moreover, its diameter was 32.7 cm and it was 19.9% less than that of Scots pine. The Student’s test showed that the diameter of Austrian pines is significantly less than that of Scots pines (tfact = 4.83, tSt = 1.98). The stands are normal by their selection structure; the trees of the second breeding category at the age of 117 made 14% of all trees. At that, more than half of the trees had straight trunks. Over the last 7 years, the stands’ health has worsened. Thus, the trees of excellent condition made 7% only. In severe steppe conditions in Veseli Bokovenky Dendrology Selection Forest Experemental Center, Kirovohrad Region, Austrian pine had an alley arrangement and was growing accoding to the VI productivity class. The average height of the 80–82-year-old trees was 17.2 m and their diameter was 28.1 cm. According to the yield tables, Austrian pine trees had 3% better height indices and 57.9% better diameter ones compared to Scots pine trees of the same age and productivity class. Most of the trees had straight trunks. The trees of I and II selection categories made 20.5%. At that, the share of minus trees was considerable, namely 36.4%. The trees of good and satisfactory conditions (73.3%) prevailed, 17.8% of trees had unsatisfactory condition. Almost all the trees had formed cones. The stand in Neskuchanske Forestry in the State Enterprise “Trostyanets Forest Economy” in Sumy Region in fresh fairly fertile site had the III productivity class. The height of 114-year-old Austrian pine trees ranged from 21.5 to 24.5 m, their diameter varied from 29.3 to 57.3 cm. Scots pine trees in this stand had the height from 22.5 to 25.0 m and diameter from 30.6 to 43.0 cm. Black pine had an average height which was 6.4% inferior to that of Sсots pine. However, its average diameter was 16.9% higher than that of Scotch pine. The Student’s test showed a significant difference (height tfact = 2.9, diameter tfact = 2.5, tSt = 2.04 at P = 0.95). In the State Enterprise “Kharkiv Forest Research Station” arboretum, in the fresh fertile site, where Austrian and Scots pines are planted as alleys, Austrian pine had the I productivity class and Scots pine Ia. Austrian pine had the height variation level twice as high as Scots pine (13.6% vs. 7.4%). The Scots pine trees with straight trunks made 25%, while only 16.7% of Scots trees had straight trunks. The analysis of the 27-year-old mix forest stand on eroded lands in the Oleksandrivske Forest Economy showed that the conservation status of Austrian pine was 33%; that of English oak was 35%. The growth of Scots pine in the fresh fairly fertile site corresponds to the 1B productivity class, the growth of the rest of the species – to the I class. The yield table data demonstrated that Scots pine trees were 9.4% higher and 56.6% wider in their diameter. At that, Austrian pine trees dropped 14.7% behind in their height and 1.0% in their diameter. Trees of the 1st selection category were only among Austrian pines (2.4%). The total share of trees of I and II categories were 26.1%. The proportion of trees of 2nd selection category was 18.2% for Scots pine and 13.8% for English oak. The comprehensive assessment of the studied stands provided the following data. Austrian pine scored more points than Scotch pine (3/4 cases) and the same number of points in the 27-year-old stand. Therefore, it is considered promising for planting forests and protective stands on eroded soils as well as for landscaping. Сonclusions Austrian pine drops behind Scotch pine by height in all studied stands, but in most of the cases it prevails by diameter, has higher-quality trunks and is of better condition. According to the results of the comprehensive assessment, Austrian pine has scored more or the same points with Scotch pine. Austrian pine is recognized as promising for planting forests and protective stands on eroded soils in central and north-eastern parts of Ukraine. Furthermore, with moderate recreational load it is able to perform ameliorative functions, and thanks to its high ornamentality it is promising for landscape gardening. To further introduce the species, it is necessary to expand the forest seed plantation base, namely: to select plus trees, to establish clonal and family seed plantations. At the present stage it is recommended to use the best stands for harvesting cones. 2 Figs., 3 Tables, 20 Refs.

Мониторинговые исследования за растительными объектами позволяют получить массив данных по особенностям роста, фенологии, развитию генеративных органов, характеру плодоношения, качеству семян, устойчивости к стресс-факторам, т.е. по показателям, которые находятся в функциональной зависимости между собой и позволяют судить о степени экологической пластичности растений. Для обоснования перспективности видов рода Juniperus, дальнейшего прогнозирования уровня адаптивности видов за пределами естественного ареала необходима достоверная и актуальная информация об успешности адаптации интродуцентов в условиях урбанизированных территорий малолесных регионов. Цель исследований – обоснование перспективности использования видов рода Juniperus на основе изучения их биологического потенциала в условиях интродукции. Объектами исследований являлись виды рода Juniperus: J. virginiana L., J. sabina L., J. communis L. и их формы, интродуцированные в дендрологических коллекциях Волгоградской области: ФНЦ агроэкологии РАН, кадастр №34:34:000000:122, 34:34:060061:10 и Нижневолжской станции по селекции древесных пород, № 34:36:0000:14:0178. Обследование проводилось маршрутным методом. Изучение сезонных ритмов развития интродуцентов проводилось методом фенологических наблюдений. Характеристика декоративности, роста и развития трех видов Juniperus L. (J. sabina L., J. virginiana L., J. communis L.) в условиях каштановых почв Волгоградской области, оценка репродуктивной способности, особенности размножения различных видов в культуре выявлялись по методикам ФНЦ агроэкологии РАН. Для определения характера плодоношения объектов исследования использовался метод определения массы 1000 семян, взвешивание проводили на весах марки «MASSA-K». Для математической обработки данных использовали стандартные алгоритмы: средняя арифметическая с абсолютной и относительной ошибками; коэффициент вариации для оценки особенностей репродуктивных процессов; достоверность различий между отдельными показателями. Приведена характеристика декоративности, роста и развития трех видов Juniperus L. (J. sabina L., J. virginiana L., J. communis L.) в условиях каштановых почв Волгоградской области. Дана оценка репродуктивной способности, выявлены особенности размножения различных видов в культуре. По комплексу изученных количественных показателей семенного материала установлено, что семена можжевельника виргинского (Juniperus virginiana L.) (10 г) меньше по массе семян обыкновенного практически в полтора раза; масса семян можжевельника казацкого (Juniperus sabina L.) (24 г) больше по массе семян можжевельника обыкновенного в полтора раза и почти в два с половиной раза больше можжевельника виргинского в сравнении с нормативными данными по можжевельнику обыкновенному (масса 1000 шт. которых составила 16 г). Изучение характера плодоношения можжевельника виргинского (J. virginiana) показало, что в 10,0 граммах шишкоягод содержится в среднем 156 ягод и 270 шт семян, выход чистых семян – 15,84 % от массы плодов. В 10,0 граммах шишкоягод можжевельника казацкого (J. sabina) содержится в среднем 86 ягод и 170 шт семян, выход чистых семян – 20,09 % от массы плодов. Установлено, что для озеленения урбанизированных территорий Волгоградской области Juniperus virginiana рекомендуется использовать в аллейных насаждениях, в чистых группах и в качестве второго яруса в насаждениях Betula, Robinia, Pseudotsuga, Larix. Juniperus sabina наиболее ценен для декорирования и укрепления склонов. В садах и парках общего пользования его применение ограничивается, а при озеленении детских учреждений исключается (хвоя и плоды ядовиты). В Волгоградской области Juniperus communis и его формы могут быть использованы на бедных песчаных почвах в групповых посадках, на опушках и в формованных живых изгородях. Пирамидальные формы пригодны на партерах, карликовые – для оформления каменистых участков. Форма с золотистой окраской в небольших группах на газоне. Monitoring studies of plant objects provide an array of data on the characteristics of growth, phenology, the development of generative organs, the specifics of fruiting, seed quality, and resistance to stress factors, i.e. indicators that are in a functional relationship with each other and allow estimating the degree of environmental plasticity of plants. To justify the prospects of species of the Juniperus genus, forecast the adaptability level of species outside the natural range, reliable and relevant information on the success of adaptation of introduced plants in urbanized areas of sparsely wooded regions is necessary. The purpose of the research is to justify the prospects of using species of the Juniperus genus based on the study of their biological potential under the conditions of introduction. The objects of research were species of the Juniperus genus: J. virginiana L., J. sabina L., J. communis L. and their forms introduced in dendrological collections of the Volgograd Region: Federal Research Center of Agroecology of the Russian Academy of Sciences, Cadastre No. 34:34:000000:122, 34:34:060061:10 and the Lower Volga tree breeding station, No. 34:36 0000:14:0178. The survey was conducted by the route method. The seasonal development rhythms of introduced plants were studied by the method of phenological observations. The characteristics of decorativeness, growth, and development of three species of Juniperus L. (J. sabina L., J. virginiana L., J. communis L.) in chestnut soils of the Volgograd Region, the assessment of reproductive ability, and the reproduction specifics of various cultivated species culture were revealed according to the methods of the Federal Scientific Center of Agroecology of the Russian Academy of Sciences. To determine the fruiting specifics of the study objects, the method of determining the mass of 1000 seeds was used; weighing was performed using a MASSA-K brand balance. For mathematical data processing, standard algorithms were used: the arithmetic mean with absolute and relative errors; the coefficient of variation to assess the characteristics of reproductive processes; the significance of differences between individual indicators. The characteristics of decorativeness, growth, and development of three species of Juniperus L. (J. sabina L., J. virginiana L., J. communis L.) in chestnut soils of the Volgograd Region are described. An assessment of reproductive ability is given, the features of reproduction of various cultivate species are revealed. According to the complex of the studied quantitative indicators of the seed material, it was found that the weight of seeds of Virginian juniper (Juniperus virginiana L.) (10 g) was almost half of the weight of common juniper seeds; the weight of the seeds of savin juniper (Juniperus sabina L.) (24 g) exceeded the weight of the seeds of common juniper by 1.5 times and that of Virginian juniper – by 2.5 times, in comparison with the standard data for common juniper (weight of 1000 pcs. – 16 g). A study of the fruiting specifics of Virginian juniper (J. virginiana) showed that 10.0 grams of conifer berries contained an average of 156 berries and 270 seeds, the yield of pure seeds was 15.84% of the fruit weight; 10.0 grams of cone berry of savin juniper (J. sabina) contained an average of 86 berries and 170 seeds, the yield of pure seeds was 20.09% of the fruit weight. It has been established that for landscaping the urban areas of the Volgograd Region, Juniperus virginiana is recommended to be used in alley stands, in clean groups, and as a second tier in the stands of Betula, Robinia, Pseudotsuga, Larix. Juniperus sabina is most valuable for decorating and strengthening slopes. In gardens and public parks, its use is limited, and when planting children's institutions, it is excluded (needles and fruits are poisonous). In the Volgograd Region, Juniperus communis and its forms can be used on poor sandy soils in group plantings, at the edges, and in molded hedges. Pyramidal forms are suitable in the level spaces, dwarf forms – for the design of rocky areas. The form with a golden color can be used in small groups on lawns.

Leaf litter or organic matters can decompossed by microorganisms like fungi.This study aims to determine the ability of growth and the rate of decomposition of Suren (Toona sureni Merr.) rhizosphere fungi isolates on various organic media. The testing process was carried out at the Biotechnology and Tree Breeding Laboratory, Faculty of Forestry, Hasanuddin University, Makassar. The research method consisted of making fungi growing media, rejuvenating isolates and making organic media from teak leaf litter (Tectona grandis), Jabon (Anthocephalus cadamba), and Mahogany (Swietenia macrophylla). The highest growth of mycelium was found in Fusarium sp. The growth of the five best fungi isolates in the formulation of mahogany leaf litter and the highest average decomposition rate in the combination treatment of mahogany leaf litter and Fusarium sp.

Tree breeding in holes has been recorded for the Common Swift (Apus apus) mainly in Northern Europe and Siberia. This behaviour, considered as ancestral, has also been noted in Corsican forests. Although marginal in terms of numbers, it is a perennial phenomenon. We present here a synthesis on the distribution and the characteristics of nesting sites, and we compare these breeding sites to the occurrences in continental Europe and Northern Africa. Our data add to the body of arguments in favour of the preservation of mature forests of the Corsican Pine on the island., Thibault Jean-Claude, Armand Thomas, Beuneux Grégory, Cibois Alice, Courtois Jean-Yves, Seguin Jean-François. Common Swifts (Apus apus) nesting in mature pine forests in Corsica. In: Ecologia mediterranea, tome 46 n°1, 2020. pp. 75-82.

RUSSIAN JOURNAL OF FOREST SCIENCE, 2020, No. 5, P. 442–450 OPTIMAL AGE OF THE ELITE TREES’ GENETIC PROPERTIES ASSESSMENT IN TEST CULTURES OF A NORWAY SPRUCE A. S. Bondarenko 1 , А. V. Zhigunov 2 1 Saint-Petersburg Forest Research Institute, Instituskii pr. 21, 194021, St. Petersburg, Russia E-mail: asbond@mail.ru 2 Saint-Petersburg State Forest Technical University, Institutskii per. 5, 194021, St. Petersburg, Russia E-mail: a.zhigunov@bk.ru Received 27 February 2018 Estimation of the time when individual trees and half-sib families acquire stable rank position in progeny tests makes it possible to determine the optimal age best suited for estimation of genetic properties of trees with respect to their seed progeny. Individual trees and half-sib families in Norway spruce ( Picea abies L.) stands may significantly change their rank position in the first 10–15 years of their life, whereas later on, their rank positions become stable. Starting from age class 2 (21 years and older), the rank positions of Picea abies families become relatively stable with respect to the growth rate. At the age exceeding the age of the final estimation of families in progeny tests (40 years for Picea abies ), families may also change their rank positions but not so significantly. The group of half-sib families with average rates of growth is characterized by a more significant change in its ranking position as compared with the families from extreme ranking groups. Based on the results of the research, it is recommended that the genetic properties of Picea abies families in progeny tests in the North-West of Russia be estimated prior to the age of 20. Key words: progeny tests, Picea abies, seed progeny, growth rate, growth group, differentiation, cluster analysis. 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International audience; Despite recent developments in molecular markers, most forest tree breeding programmes do not use them routinely. One way to integrate markers would be to use them for pedigree reconstruction after a simplified mating design through polymix or open-pollinated breeding. Thanks to the latest developments in the POPSIM simulator, various breeding strategies, including some based on paternity recovery, were evaluated with specified constraints on the level of diversity over breeding cycles. These simulations were carried out in two case studies: the French Pinus pinaster (Ait.) and the New Zealand Eucalyptus nitens (H. Dean & Maiden) Maiden breeding programmes. The Pinus pinaster case study produced lower genetic gain for the polymix breeding strategy with paternity recovery compared with double-pair mating or optimal-contribution strategies. However, the polymix breeding strategy could be of interest if the mating design is faster to complete. In the Eucalyptus nitens case study, pedigree recovery was shown to be a mandatory step to controlling the erosion of diversity over breeding cycles. In both cases, the strategies based on pedigree reconstruction were applicable with a limited level of genotyping. Finally, these simulations allow some general recommendations to be drawn to help breeders when designing a strategy for forest tree breeding.; Dans la plupart des programmes d’amélioration forestiers, les marqueurs moléculaires ne sont pas utilisés en routine malgré les développements récents en génomique. Une des possibilités d’intégration des marqueurs serait de les utiliser pour reconstituer les pedigrees après des croisements simplifiés de type polycross ou pollinisation libre. Grâce aux derniers développements du simulateur POPSIM, différentes stratégies d’amélioration, dont certaines incluant une recherche de paternité, ont été évaluées avec des contraintes spécifiques relatives au niveau de diversité au cours des cycles de sélection. Ces simulations ont été menées pour deux cas d’étude : les programmes d’amélioration de Pinus pinaster (Ait.) en France et d’Eucalyptus nitens (H. Deane & Maiden) Maiden en Nouvelle-Zélande. Le cas d’étude Pinus pinaster révèle un gain génétique moindre pour la stratégie de croisements polycross avec recherche de paternité en comparaison aux stratégies de croisements double-paire ou de contributions optimales. Néanmoins, la stratégie de croisements polycross pourrait être intéressante si elle permet une réduction de la durée des cycles de sélection. Pour le cas d’étude Eucalyptus nitens, la reconstitution de pedigree est une étape obligatoire pour contrôler l’érosion de la diversité au cours des cycles de sélection. Dans les deux cas, les stratégies basées sur la reconstitution de pedigree peuvent être mises en œuvre en génotypant un nombre limité d’individus. Finalement, ces simulations ont permis de formuler des recommandations générales afin d’aider les sélectionneurs à élaborer des stratégies d’amélioration chez les arbres forestiers.

Full understanding and control of pine wilt disease (PWD) is a work in progress and breeding for disease resistance constitutes an essential management strategy for reducing its impact, as evidenced by advanced breeding programs in countries such as Japan. Since Pinus radiata is one of the most commercially relevant species in northern Spain, we designed a study to assess genetic variation in susceptibility to this pathogen using 44 P. radiata half-sib families from the Galician breeding program. Three Bursaphelenchus xylophilus (pinewood nematode, PWN) inoculation experiments were performed to evaluate disease-related variables, estimate genetic parameters, and study sources of genotype by environment interaction (G × E). We also looked at differences in the constitutive chemical compounds of susceptible and non-susceptible individuals. The results showed great variation in PWN susceptibility, with survival rates for P. radiata families ranging from 0% to 90%. In addition, heritability estimates (hi2 = 0.43, hf2 = 0.72) and genetic gain (&gt, 26% selecting 50% of the families) were both moderately high for survival. Significant differences in several constitutive chemical compounds were found between susceptible and non-susceptible seedlings in the two susceptibility groups considered. These results confirm the potential of breeding to obtain P. radiata genotypes that are resistant to pine wilt disease and open possibilities for mitigating its future impact on P. radiata stands.

The objective of this study was to evaluate photosynthetic performance based on gas exchange traits, chlorophyll a fluorescence, and leaf water potential (ΨL) in nine Hevea brasiliensis genotypes from the ECC-1 (Élite Caquetá Colombia) selection and the cultivar IAN 873 (control) in response to different climatic (semi-humid warm and humid warm climates), seasonal (dry and rainy periods), and hourly (3:00 to 18:00) variations that can generate stress in the early growth stage (two-year-old plants) in two large-scale clonal trials in the Colombian Amazon. The photosynthetic performance in 60% of the Colombian genotypes was slightly affected under the conditions with less water availability (dry period, semi-humid warm site, and between 9:00 and 15:00 h), as compared with IAN 873, whose affectation was moderate in terms of photosynthesis rates, but its water conservation strategy was strongly affected. The ECC 90, ECC 83, and ECC 73 genotypes had the best photosynthetic performance under conditions of greater water limitation, and ECC 35, and ECC 64 had a higher water status based on the leaf water potential, with intermediate photosynthetic performance. This germplasm has a high potential for selection in rubber tree breeding programs in future scenarios of climate change in the Colombian Amazon.

The objective of this work was to assess the genetic variability of Araucaria cunninghamii in a provenance test and to estimate the genetic gains in its wood production, based on different selection intensities. The trial was established in Luís Antônio, in the state of São Paulo, Brazil, using open-pollinated seed from Queensland, Australia. The experimental design used was a randomized complete block with six replicates, and four plants per plot. Diameter at breast height (DBH), stem form, and survival were measured at 29 years after planting. Significant differences were detected among provenances. The coefficient of genotypic variation between provenances was high (60%) for DBH and stem form. The mean values for DBH and stem form were 23.21 cm and 4.50, respectively. The provenances Langkelly Creek, Brooweena L.A., Yarraman, and St. Agnes showed the best performance for DBH, and Imbil Seed Orchard, Brooweena L.A, St. Agnes, St. John, and Yarraman, for stem form. Genetic gains ranged from 0.5 to 24.8% for DBH, and from 0.9 to 3.5% for stem form. Resumo: O objetivo deste trabalho foi avaliar a variabilidade genética de Araucaria cunninghamii, em teste de procedência, e estimar ganhos genéticos para a produção de sua madeira, com base em diferentes intensidades de seleção. O experimento foi estabelecido em Luís Antônio, no estado de São Paulo, Brasil, com sementes de polinização aberta coletadas em Queensland, Austrália. O delineamento experimental utilizado foi o de blocos ao acaso, com seis repetições e quatro plantas por parcela. O diâmetro à altura do peito (DBH), a forma do fuste e a sobrevivência foram medidos 29 anos após o plantio. Diferenças significativas foram detectadas entre as procedências. O coeficiente de variação genotípica foi alto (60%) para DBH. Os valores médios de DBH e forma do fuste foram de 23,21 cm e 4,50, respectivamente. As procedências Langkelly Creek, Brooweena L.A., Yarraman e St. Agnes apresentaram melhor desempenho em DBH, e Imbil Seed Orchard, Brooweena L.A., St. Agnes, St. John e Yarraman, em forma do fuste. Os ganhos estimados com a seleção variaram de 0,5 a 24,8%, para DBH, e de 0,9 a 3,5%, para forma do fuste.

The productivity of forests has been linked to the sensitivity of tree growth to meteorological conditions and their fluctuations, hence moderation of tree sensitivity is one of the goals for climate-smart forest management. For this, tree breeding is among the most effective means, particularly if breeding populations are supplemented with genotypes (provenances) adapted to the expected climates. Nonetheless, heritability of traits is essential for their improvement by breeding. In this study, heritability of growth sensitivity of south-eastern Baltic provenances of Scots pine differing by field performance to meteorological conditions was assessed combining methods of quantitative genetics and dendrochronology. Five parallel provenance trials within the south-eastern Baltic region were investigated. The effects of regional weather drivers of growth (moisture regime in summer, temperature regime in preceding summer and in the dormancy period) were estimated, yet their strengths differed among the provenances, indicating local specialization of metapopulations of Scots pine. The heritability of growth sensitivity to these factors ranged from low to moderate, similarly as observed for the morphometric traits within the region, however, the provenance (genetic) variation appeared to be higher. The differences in heritability of responses, however, indicated uneven adaptive significance of weather conditions. Although the estimates were based on a limited set of genotypes implying caution in the extrapolation of results, the weather-growth relationships and their heritability indicate that sensitivity of growth is a complementary trait aiding breeding of forest reproductive material best suited for future climates. Heritable weather-growth relationships also imply a high potential for forest breeding to moderate the sensitivity of the trees.

Hevea brasiliensis (rubber tree) is a large tree species of the Euphorbiaceae family with inestimable economic importance. Rubber tree breeding programs currently aim to improve growth and production, and the use of early genotype selection technologies can accelerate such processes, mainly with the incorporation of genomic tools, such as marker-assisted selection (MAS). However, few quantitative trait loci (QTLs) have been used successfully in MAS for complex characteristics. Recent research shows the efficiency of genome-wide association studies (GWAS) for locating QTL regions in different populations. In this way, the integration of GWAS, RNA-sequencing (RNA-Seq) methodologies, coexpression networks and enzyme networks can provide a better understanding of the molecular relationships involved in the definition of the phenotypes of interest, supplying research support for the development of appropriate genomic based strategies for breeding. In this context, this work presents the potential of using combined multiomics to decipher the mechanisms of genotype and phenotype associations involved in the growth of rubber trees. Using GWAS from a genotyping-by-sequencing (GBS) Hevea population, we were able to identify molecular markers in QTL regions with a main effect on rubber tree plant growth under constant water stress. The underlying genes were evaluated and incorporated into a gene coexpression network modelled with an assembled RNA-Seq-based transcriptome of the species, where novel gene relationships were estimated and evaluated through in silico methodologies, including an estimated enzymatic network. From all these analyses, we were able to estimate not only the main genes involved in defining the phenotype but also the interactions between a core of genes related to rubber tree growth at the transcriptional and translational levels. This work was the first to integrate multiomics analysis into the in-depth investigation of rubber tree plant growth, producing useful data for future genetic studies in the species and enhancing the efficiency of the species improvement programs.

Intraspecific genetic variation in drought response is expected to play an important role in determining the persistence of tree populations in global change as it (1) allows for spontaneous selection and local adaptation of tree populations, (2) supports assisted seed transfer of less-drought-sensitive provenance, and (3) enables the integration of drought-sensitivity traits into tree breeding. Estimating the potential of such adaptation options requires quantitative genetic knowledge of drought sensitivity across significant parts of species distributions and a comparative assessment of genetic variation within economically and ecologically important tree species. We quantified genetic variation within and among populations of four conifers growing within common garden experiments in the drought-prone eastern Austria. This region experienced three strong drought periods between 1980 and 2010 that resulted in significant reductions in radial growth. Among the four tested species, Douglas-fir revealed the highest resistance during drought and silver fir the best recovery after drought, while European larch and Norway spruce showed the lowest resistance. High genetic variation among populations and phenotypic stability across all three drought events was found for Norway spruce and silver fir, but not for the other species. Heritability and evolvability of drought traits, both approximated via genetic repeatability, revealed strong differences among populations of all four species. Repeatability and evolvability for resistance were highest in Norway spruce and, for recovery, highest in European larch. Our comparison indicates that the mean drought sensitivity of a species is not related to the intraspecific genetic variation in drought response. Thus, also highly drought-sensitive species, such as Norway spruce and European larch, harbor significant genetic variation in drought response within and among populations to justify targeted tree breeding, assisted gene flow, and supportive forest management to foster local adaptations to future conditions.

Made available in DSpace on 2022-04-28T19:40:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Araucaria angustifolia provides timber, edible seeds and pharmaceuticals and has a unique ecology (once shared with that of the dinosaurs), yet is now threatened with extinction. Here, we assess and reconcile the counteracting goals of enhancing genetic fitness and maintaining genetic variability during ex-situ conservation of A. angustifolia in a provenance-and-progeny test to improve growth vigor. After 33 years, survival, height, diameter at breast height, and volume of trees were determined. Sixteen selection scenarios were tested using two strategies: Selection among and within progenies, and selection only within progenies, each one for eight values of selection intensity of total survival in the trial (7.6, 11.5, 15.3, 19.1, 22.9, 26.8, 30.6, and 34.4%). The variance components and genetic parameter estimates were determined using REML/BLUP. There was significant genetic variation among provenances and progenies for all traits. For all growth-phenotype traits, the heritability at mean (0.419-0.542) and within progeny level (0.186-0.207) indicate the potential for tree improvement by selection among and within progenies. The selection strategy enhanced growth phenotype whilst maintaining an effective population size of 19.1% selected individuals within progenies (three females and two males). This preserved sufficient genetic variability among and within provenances, and resulted in genetic gain, providing higher-value seed production. Instituto Florestal de São Paulo - IF Empresa Brasileira de Pesquisa Agropecuária - Embrapa Florestas Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista Júlio de Mesquita Filho- UNESP Institute for Global Food Security School of Biological Sciences Queen's University Belfast, Chlorine Gardens Faculdade de Engenharia de Ilha Solteira Universidade Estadual Paulista Júlio de Mesquita Filho- UNESP

The study aims to analyse the stability of the narrow crowned Norway spruce (pendula form) compared to the normal spruce form (pyramidalis form) and the hybrids of the two forms, in 5 field trials (Comandău, Lepşa 12, Ilva Mică and Voineasa) located in the Romanian Carpathians. Trees height (Th), breast height diameter (Dbh), height growth of the last year, crown diameter (Cd), number of branches per whorl (Nbw) and dominant branch diameter (Dbd) traits were measured and survival rate (Sr) was determined, at 20 years old. Also, branches finesse (Bf), trees volume (Tv) and trees slenderness (Ts) were calculated. In order to compare the wood density (Cwd) there were collected cores. In all trials ANOVA revealed significant (p 0.05) differences between the two forms of spruce and the hybrids (mainly between those that have a different crown form mother), especially for the stability and quality traits. Factorial ANOVA revealed a high influence (p 0.001) of the locality and also a significant influence (p 0.05) of the locality × spruce form interaction. The factor "form" was significant for some traits involved in Norway spruce stability (Ts, Cd, Nbw). The pendula trees present higher values for Sr, Dbh and Tv, and lower values for Ts, Cd, Nbw, Dbd and Bf, compared to pyramidalis spruce form, which showed a higher stability. Heritability was in generally low (h

Acacia × mangiiformis Maslin & L.A.J.Thomson, hybrida nova, is described. Its parents are Acacia auriculiformis A.Cunn. ex Benth. and A. mangium Willd., two well-known and important plantation species in Asia and elsewhere. Acacia × mangiiformis arose naturally in the Western Province of Papua New Guinea and in recent decades has become widely cultivated in southeast Asia (Indonesia, Malaysia, Thailand and Vietnam), India, and to a lesser extent in China and Taiwan. The tree has often been referred to as “Acacia hybrid” in forestry literature. Acacia × mangiiformis has morphological and other characteristics that are intermediate between its parents. Furthermore, it often has a faster growth rate, superior bole form and is more drought-tolerant than its parent species The hybrid is used primarily for pulp production but also has uses as solid wood products and fuelwood. The wood is similar to that of A. mangium but has a higher density and is more suitable for products where strength is important; it is also less susceptible to termite attack than are its parent species. Ten high-performing commercial clones of Acacia × mangiiformis have been developed in Vietnam and more are being selected. The formal naming of this important hybrid is dedicated to Professor Le Dinh Kha (formerly of Forest Science Institute of Vietnam), an outstanding researcher, supervisor, and authority on tree breeding who conducted much of the original research and promotion of Acacia × mangiiformis in Vietnam.

Spanish red cedar, Cedrela odorata L. (Meliaceae), is a valuable timber tree in tropical American forests. Existing demand for elite individuals endangers the conservation of interesting germplasm, prompting the development of efficient protocols for the establishment of orchards for tree breeding. Based on previous work regarding grafting adult individuals onto young rootstocks, superior trees from Calakmul Biosphere Reserve in Campeche, Mexico were employed as a source of explants for plant regeneration after successive rounds of grafting and micrografting onto juvenile rootstocks. The results showed that root length and appearance, internode distance, leaf length and number, and plant height values for trees derived from successive rounds of grafting and micrografting were similar to those obtained from juvenile trees derived from seeds, suggesting that developmental traits associated with reinvigoration were partially induced following the reported procedure. This protocol may be useful for the propagation of mature elite trees belonging to the Meliaceae family.

Like other outcrossing species, Scots pine (Pinus sylvestris L.) is thought to carry a “genetic load” of deleterious recessive alleles. When these alleles occur as homozygotes in inbred progeny, their expression can give rise to “inbreeding depression”. Although this phenomenon has been studied in several conifer species through selfing, few studies have quantified inbreeding depression in crosses with lower levels of relatedness between parents. We report here on the generation of a set of F3 study materials in Scots pine in which 142 families arose from a mating design among 49 F2 parents, representing nine levels of expected inbreeding coefficients between 0.0 and 0.5, and repeated over two consecutive seasons. Whereas the numbers of extractable seeds were unaffected by inbreeding, the proportion with fully developed embryos was strongly affected. This was expressed as inbreeding depression in the yield of full seeds per cone but not in their mean mass. Levels of germination of these full seeds were affected by inbreeding, but the depression was rather small and only weakly significant. The roles of pollen competition and polyembryony in mitigating the impact of inbreeding depression are discussed. The materials have been outplanted for future assessment of inbreeding depression on growth and survival.

Insect pests are part of natural forest ecosystems contributing to forest rejuvenation but can also cause ecological disturbance and economic losses that are expected to increase with climate change. The white pine or spruce weevil (Pissodes strobi) is a pest of conifer forests in North America. Weevil–host interactions with various spruce (Picea) species have been explored as a genomic and molecular reference system for conifer defence against insects. Interactions occur in two major phases of the insect life cycle. In the exophase, adult weevils are free‐moving and display behaviour of host selection for oviposition that is affected by host traits. In the endophase, insects live within the host where mobility and development from eggs to young adults are affected by a complex system of host defences. Genetic resistance exists in several spruce species and involves synergism of constitutive and induced chemical and physical defences that comprise the conifer defence syndrome. Here, we review conifer defences that disrupt the weevil life cycle and mechanisms by which trees resist weevil attack. We highlight molecular and genomic aspects and a possible role for the weevil microbiome. Knowledge of this conifer defence system is supporting forest health strategies and tree breeding for insect resistance., A review of conifer defences against a forest insect pest system. The review covers the complex conifer defence syndrome through which resistant trees cope with insect attack. Knowledge of the conifer defence system supports development of pest management and forest health strategies.

Genomics-assisted tree breeding (GATB) is an emerging biotechnology method that has the potential to produce improved planting stock in selected traits, such as greater volume or higher wood quality, more quickly and effectively compared with traditional field-based breeding (TB) methods. In this study, we conducted an ex-ante stand-level financial benefit-cost analysis that is linked to a provincial tree growth and yield projection model to investigate the potential financial benefits of using improved white spruce (Picea glauca (Moench) Voss) and lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) planting stock identified via alternative tree improvement strategies (i.e. GATB vs. TB methods) for forest companies in the province of Alberta, Canada. With consideration of major tree breeding and establishment costs, expected sawlog price premiums at harvest, a shorter breeding cycle time, and additional genetic gain in volume achieved from using the GATB method relative to the TB method in the financial analysis; this study found that the use of GATB-selected third-generation planting stock was difficult to justify economically alone compared with TB-selected seedlings under the current sawlog market value and the current planting rate with improved stock in the province. However, results of our sensitivity analysis also revealed that the GATB method is: (1) more financially supported at lower discount rates; (2) strongly supported through decreased seedling costs with increased areas planted with improved stock; and (3) strongly supported through an increase in log price premiums at harvest resulting from potentially better wood quality and higher volume production relative to TB-selected stock. The findings of this study highlight several important market and biophysical factors that forest managers should take into account when adopting biotechnology in forestry.

This study was carried out in the clone archive of old Scots pine Pinus sylvestris L. trees located in the Augustowska Primeval Forest. The aim of the study was to determine the intra-clonal diversity among quantitative and qualitative traits of the vegetative progeny of Scots pine trees older than 200 years. Our analyses included traits such as survival rate, height and diameter at breast height (DBH), stem straightness, length and width of the crowns as well as branch thickness and growth angle. There was no significant correlation between the age of mother trees and the traits of their vegetative progeny. However, mother trees did affect the survival of the progeny. In overall, the survival rate of grafts in the archive is high (about 80% at the age of 13 years) and there have been no significant fluctuations in recent years. Nevertheless, the variability of quantitative traits among vegetative progeny was high with the average height ranging from 2.16 m up to 6.71 m, and in the case of DBH, ranging from 3.23 cm to 12.1 cm. Both, height of trees and their DBH, were significantly different among the analysed clones. These intra-clone differences in growth traits indicate a high environmental impact on the growth and performance of clones. However, the diversity of quantitative and qualitative traits is comparable to the differences observed in the economic seed orchards with seedlings at a similar age. Most of the genotypes planted in the archive are fully viable and have matured to the stage of seed production. The clone archive can thus be viewed as both, a conservation effort and to obtain valuable seeds from the point of view of tree breeding. Therefore, establishing archives of tree clones using valuable genotypes is an effective method of conserving individual genotypes even of very old individuals.

Avocado (Persea americana) is an important tropical and subtropical fruit tree crop. Traditional tree breeding programs face the challenges of long generation time and significant expense in land and personnel resources. Avocado selection and breeding can be more efficient and less expensive through the development of molecular markers for the estimation of germplasm genetic diversity, marker-assisted selection (MAS), and creation of linkage maps. Two important breeding resources, the world's two largest avocado mapping populations and an extensive germplasm collection, are housed at the USDA-ARS Subtropical Horticulture Research Station (SHRS) in Miami, Florida. However, to use these resources to their greatest advantage, many thousands of genetic markers are necessary. Here, we describe the development of the first set of avocado genetic markers based on single-nucleotide polymorphism (SNP) variation in expressed genes. RNA sequencing was used both to build a reference transcriptome from 'Hass', the most widely grown avocado cultivar worldwide, and to identify SNPs by alignment of RNA sequences from the mapping population parents to the ˈHassˈ transcriptome. This study provides a new genomic tool for the avocado community that can be used to assess the genetic diversity of avocado germplasm worldwide and to optimize avocado breeding and selection programs by complementing traditional breeding methods with molecular approaches, thus increasing the efficiency of avocado genetic improvement.

The quality indicators of compatible seed lots of Pinus sylvestris L. have been studied based on the analysis of medium-sized samples from the Forest Seed Laboratory of Vinnytsia during 2006–2015. The quality indicators of seeds have been analyzed for purity, weight of 1000 seeds, germination, energy of germination and pathogen contamination. Analysis of quality indicators of seed from permanent forest seed base has been done separately. We have found that in forest plantations of Zhtomyr region of Ukraine the quality of Pinus sylvestris L. seeds is high. The average value of a specie seeds technical germination is 84,2–93,5%. Among the 653 compatible lots the seeds of I, II and III quality classes are distributed as follows: 40,6%, 44,2% and 14,7% respectively; the substandard seeds reach only 0,5%. The total mass of homogenous parts of seeds was from 1452 to 2946 kg during the period of investigation, which is primarily connected with productivity over the years and the weather conditions on the flowering stage, pollination and seed maturation. The intensive productivity of pine seeds is every 2-4 years and very rare in conditions of the Zhytomyr region. About 653 Scots pine seed lots of total weight of 22492 kg was harvested by forestry enterprises of Zhytomyr region over the last 10 years. The 139 lots of 4372 kg total weight where harvested from forest tree breeding seeds objects. Depending on the seed productivity of the year on the facilities of seed objects annually harvest 300-400 kg of seeds. The harvesting volumes of pine seeds was increased to 700 kg per year during the last two years. The intensity of harvested seed was increased from forest tree breeding objects in range 12-18% and increased to 28-30% of total harvested seeds for the last two years (2014, 2015). Increasing the weight of harvested seed from forest tree breeding objects during the last two years can be explained by high yield years and the beginning of mass production from these objects that were created in previous years. Seeds of objects of permanent forest seed base characterized by high quality. Thus, the seed class 1 set 34%, 2 class - 54% and only 12% of seeds 3 class overall quality from quantity. No cases of harvesting seeds from objects of permanent forest seed base, that would not meet the standard. Expansion of the existing permanent forest seed base improve its position and increase the genetic level enables to provide forestry enterprises with high seed sowing qualities and valuable properties in genetic and breeding terms.

RUSSIAN JOURNAL OF FOREST SCIENCE, 2019, No. 6, P. 580-584 PHENOTYPIC SELECTION IN FOREST BREEDING – PRO ET CONTRA A. L. Fedorkov Institute of Biology, Komi Scientific Centre, Ural Branch of the Russian Academy of Sciences Kommunisticheskaya st. 28, Syktyvkar, 167982, Russia E-mail: fedorkov@ib.komisc.ru Received 21 August 2017 Here we review the issues of efficiency of phenotypic selection of plus trees in forest breeding. We analyzed Russian and foreign studies of phenotypic selection and found the reasons of different estimates of the efficiency of this approach. Parameters of genetic improvement of height and diameter resulting from phenotypic selection of plus trees of pine in forest plantations were calculated using evidence. Conclusions are made on the prospects of conventional forest selection in improvement of productivity of forests were made based on personal data and literature review. Keywords: trial plantations, phenotypic selection, plus trees. DOI: 10.1134/S0024114819060032 REFERENCES Ahtikoski A., Ojansuu R., Haapanen M., Hynynen J., Karkkainen K., Financial performance of using genetically improved regeneration material of Scots pine (Pinus sylvestris L.) in Finland, New Forests , 2012, Vol. 43, No. 3, pp. 335-348. Ahtikoski A., Salminen H., Ojansuu R., Hynynen J., Karkkainen K., Haapanen M., Optimizing stand management involving the effect of genetic gain: preliminary results for Scots pine in Finland, Canadian Journal of Forest Research , 2013, Vol. 43, No. 3, pp. 299-305. Andersson B., Elfving B., Ericsson T., Persson T., Gregorsson B., Performance of improved Pinus sylvestris in northern Sweden, Scandinavian Journal of Forest Research , 2003, Vol. 18, No. 3, pp. 199-206. Andersson B., Elfving B., Persson T., Ericsson T., Kroon J., Characteristics and development of improved Pinus sylvestris in northern Sweden, Canadian Journal of Forest Research , 2007, Vol. 37, No. 1, pp. 84-92. Andersson B., Lindgren D., Molecular and other biotech methods – options for Swedish tree breeding, In: Review of the Swedish tree breeding programme Uppsala: SkogForsk, 2011, pp. 20-27 (84 p.). Byulleten' normativnykh aktov federal'nykh organov ispolnitel'noi vlasti , 2016, 28 March. Cornelius J., The effectiveness of plus-tree selection for yield, Forest Ecology and Management , 1994, Vol. 67, No. 1, pp. 23-34. Cornelius J., Heritabilities and additive genetic coefficients of variation in forest trees, Canadian Journal of Forest Research , 1994, Vol. 24, No. 2, pp. 372-379. Fedorkov A., Lindgren D., David A., Genetic gain and gene diversity following thinning in a half-sib plantation, Silvae Genetica , 2005, Vol. 54, No. 4-5, pp. 185-189. Fedorkov A.L., Nizkozatratnaya selektsiya lesnykh drevesnykh porod (na primere sosny obyknovennoi) (Low-cost selection of forest tree species: case study of Scots pine), Lesnoe khozyaistvo , 2013, No. 2, pp. 22-24. Fedorkov A.L., Puti povysheniya effektivnosti selektsionnykh rabot v taezhnoi zone Evropeiskoi Rossii (Ways of improvement of breeding in taiga zone of the European part of Russia), Lesnoe khozyaistvo , 2011, No. 1, pp. 24-25. Haapanen M., Hynynen J., Ruotsalainen S., Siipilehto J., Kilpelainen M.-L., Realised and projected gains in growth, quality and simulated yield of genetically improved Scots pine in southern Finland, European Journal of Forest Research , 2016, Vol. 135, No. 6, pp. 997-1009. Haapanen M., Jansson G., Nielsen U.B., Steffenrem A., Stener L.-G., The status of tree breeding and its potential for improving biomass production – a review of breeding activities and genetic gains in Scandinavia and Finland , Uppsala: SkogForsk, 2015, 55 p. Jansson G., Gains from selecting Pinus sylvestris in southern Sweden for volume per hectare, Scandinavian Journal of Forest Research , 2007, Vol. 22, No. 3, pp. 185-192. Jansson G., Hansen J.K., Haapanen M., Kvaalen H., Steffenrem A., The genetic and economic gains from forest tree breeding programmes in Scandinavia and Finland, Scandinavian Journal of Forest Research , 2017, Vol. 32, No. 4, pp. 273-286. Lebedev V.G., Muratova S.A., Shestibratov K.A., Polevye ispytaniya i kommertsializatsiya biotekhnologicheskikh form lesnykh drevesnykh rastenii (The field trials and the commercialization of biotech forms of the forest woody plants), Lesovedenie , 2015, No. 5, pp. 388-400. Lebedev V.G., Shestibratov K.A., Opyt sozdaniya biotekhnologicheskikh form drevesnykh rastenii (Creation of biotechnological forms of woody plants), Lesovedenie , 2015, No. 3, pp. 222-232. Lindgren D., Karlsson B., Andersson B., Prescher F., The Swedish seed orchard program for Scots pine and Norway spruce, Seed orchards , Proc. Conf., Umea, 26–28 September 2007, Umea: SLU, 2008, pp. 142-154. 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Eucalyptus tereticornis has a wide natural geographic distribution from Papua New Guinea to South Australia (6º-38º S), therefore, it is expected the existence of important differences among provenances. Although differences in performance among provenances have been reported in several countries, the existing information is insufficient to allow the choice of the most appropriate provenance as a source of seeds for commercial plantations for humid subtropical climates. In order to evaluate the performance of 20 provenances of E. tereticornis in Uruguay and to generate information that contributes to the identification of the best provenances for humid subtropical climates, survival, individual tree volume, stem straightness and forking were assessed at 9-years-old in 4 sites in the center, north and northeast of Uruguay. Significant differences among provenances for all traits and significant provenance by site interaction for survival, individual tree volume and forking were found. No provenance was best in all sites. The Buckenbowra provenance had simultaneously high volume and survival. The absence of a clear regionalization, coupled with a significant provenance-by site interaction, suggests that local evaluation of different provenances is essential to identify appropriate seed sources, both for tree breeding and for use in commercial plantations. Resumen: Eucalyptus tereticornis es una especie que tiene una amplia distribución geográfica natural, desde Papúa Nueva Guinea hasta Australia del Sur (6º-38º S), por lo tanto, es esperable la existencia de importantes diferencias entre procedencias. Aunque se han reportado diferencias en el rendimiento entre procedencias en varios países, la información existente es insuficiente para permitir la elección de la procedencia más apropiada como fuente de semillas para plantaciones comerciales en climas subtropicales húmedos. Para evaluar el desempeño de 20 procedencias de E. tereticornis en Uruguay y generar información que contribuya a la identificación de las mejores procedencias en climas subtropicales húmedos se evaluó supervivencia, volumen individual, rectitud del fuste y presencia de bifurcaciones a los 9 años de edad, en 4 sitios en el centro, norte y noreste de Uruguay. Como resultado, se encontraron diferencias significativas entre procedencias para todas las características y significativa interacción sitio por procedencia para supervivencia, volumen individual y presencia de bifurcaciones. Ninguna procedencia fue mejor en todos los sitios. La procedencia de Buckenbowra tuvo simultáneamente un alto volumen y supervivencia. La ausencia de una clara regionalización, junto con una interacción significativa de procedencia por sitio, sugiere que la evaluación local de las diferentes procedencias es esencial para identificar las fuentes de semillas apropiadas para el cultivo de esta especie y su uso en plantaciones comerciales. Resumo: Eucalyptus tereticornis é uma espécie que apresenta ampla distribuição natural, desde Papua Nova Guiné até o Sul da Austrália (6º-38º S), portanto, espera-se a existência de diferenças importantes entre procedências. Embora diferenças de rendimento entre procedências tenham sido relatadas em vários países, as informações existentes são insuficientes para permitir a escolha da procedência mais apropriada como fonte de sementes para plantações comerciais em climas subtropicais úmidos. Para avaliar o desempenho de 20 procedências de E. tereticornis no Uruguay e gerar informações que contribuam para a identificação das melhores procedências em climas subtropicais úmidos, avaliou-se a sobrevivência, o volume individual, a retidão do fuste e a presença de bifurcações aos 9 anos de idade, em quatro locais em centro, norte e nordeste do Uruguay. Como resultado, foram encontradas diferenças significativas entre procedências para todas as características e interação sitio-procedência significativa para sobrevivência, volume individual e presença de bifurcações. Nenhuma procedência foi melhor em todos os locais. A procedencia de Buckenbowra foi simultaneamente de alto volume e sobrevivencia. A ausência de uma regionalização clara, juntamente com uma interação significativa procedência por sitio, sugere que a avaliação local das diferentes procedências é essencial para identificar fontes de sementes apropriadas para o cultivo desta espécie e para uso em plantações comerciais.

Liriodendron plants have been cultivated in many regions of the world for both wood production and landscape ornamentation. Hybrid Liriodendron varieties show obvious growth and resistance heterosis; thus, interspecies hybridization and heterosis utilization constitute the major breeding strategy for Liriodendron plants. Choosing superior crossing parents/combinations and predicting the heterosis of potential hybrid combinations will greatly improve breeding efficiency and accelerate the breeding process. To explore the relationships between genetic parameters and heterosis, we investigated dynamic changes in the genetic parameters of growth traits with age by testing 57 progeny combinations derived from six cross types in Liriodendron. Tree height (H) and diameter at breast height (DBH) were under intermediate to strong genetic control and varied among combinations, indicating that parent-pair selection or combination selection is feasible. Both heritability and combining ability (general combining ability, GCA; specific combining ability, SCA) changed with age, with narrow-sense heritability fluctuating greatly in the early stage and increasing in the late stage, and the combining abilities varied among combinations. Additionally, the GCA of Liriodendron chinense parents was higher than that of Liriodendron tulipifera and hybrid Liriodendron parents, and the SCA of L. tulipifera × L. chinense combinations fluctuated less than that of other combinations. Further, midparent heterosis (MPH) and SCA were significantly positively correlated, suggesting that SCA could be a suitable criterion for predicting growth heterosis. Our findings provide useful clues for selecting parent pairs/combinations and predicting heterosis, which will accelerate Liriodendron tree breeding and shed light on cross-breeding in other plants.

Eucalyptus pellita F. Muell. is currently the predominant tree species deployed for tree plantation establishment in some parts of Borneo, particularly Sabah state, Malaysia. Its low disease susceptibility, good growth and form, and desirable wood properties make E. pellita particularly suitable for plantation development in the wet tropical regions of south-east Asia. In spite the many positive traits, practical field observations indicate that the species is susceptible to end-splitting. There is some anecdotal evidence to suggest a genetic relationship with the incidence of end-split, although these observations were not statistically tested. This study evaluates the occurrence of end-splitting in five-year old plantation E. pellita in Sabah as affected by family and growth attributes. An existing progeny tree breeding trial, involving seeds that originated from Papua New Guinea, China, Vietnam, Australia, Sabah, and Sarawak with 106 families, was used to carry out the split assessment. Logs from the second thinning were cut into 2.2-m-long sections. The end splits were measured three days later, the incidence and severity of splitting were assessed at both the large and small ends of each log by using a designated split scoring system. The study shows that 99% of all log cross sections (per cut surface) experienced signs of splitting, with an average of 2.7 splits per cut surface. Overall, 54% of all splits were classed as ‘Three-Quarter Radial Splits’ while the occurrence of internal splits was negligible. Split severity showed a heritable and significant difference (h2 = 0.24 at p ≤ 0.05) among the family levels. Splitting was also significantly related to growth factors such as tree height and diameter at breast height (DBH). The findings suggest that end-splitting is caused by family–environment interactions. This offers the opportunity to improve the wood resource of E. pellita via breeding strategies.

Pinus greggii has potential for inclusion in temperate zone breeding programs around the world as it is frost resistant and produces high yields for pulp production. This study estimates the genetic parameters for two P. greggii progeny tests established in Telêmaco Borba, Paraná, Brazil. We evaluated diameter at breast height (DBH) and total height (H) at seven and nine years of age. The narrow-sense heritability ( h i 2) ranged from 0.225 (H, 7 years) to 0.515 (H, 9 years). The genetic correlation was high for all traits, reaching up to 0.91 between traits and 0.94 between ages. In addition, the results show the presence of Genotype x Environment interaction, and as such, the most productive and stable progeny were identified based on the Harmonic Mean of the Relative Performance of Genetic Values (MHPRVG) values. These population has genetic materials that are superior in terms of both DBH and H compared to the control and to P. greggii materials analyzed internationally. Our results contribute to the literature by providing further genetic information on this species, while also demonstrating the implications of thinning for genetic gains and effective population size.

Grafting is typically utilized to merge adapted seedling rootstocks with highly productive clonal scions. This process implies the interaction of multiple genomes to produce a unique tree phenotype. However, the interconnection of both genotypes obscures individual contributions to phenotypic variation (rootstock-mediated heritability), hampering tree breeding. Therefore, our goal was to quantify the inheritance of seedling rootstock effects on scion traits using avocado (Persea americanaMill.) cv. Hass as a model fruit tree. We characterized 240 diverse rootstocks from 8 avocado cv. Hass orchards with similar management in three regions of the province of Antioquia, northwest Andes of Colombia, using 13 microsatellite markers simple sequence repeats (SSRs). Parallel to this, we recorded 20 phenotypic traits (including morphological, biomass/reproductive, and fruit yield and quality traits) in the scions for 3 years (2015–2017). Relatedness among rootstocks was inferred through the genetic markers and inputted in a “genetic prediction” model to calculate narrow-sense heritabilities (h2) on scion traits. We used three different randomization tests to highlight traits with consistently significant heritability estimates. This strategy allowed us to capture five traits with significant heritability values that ranged from 0.33 to 0.45 and model fits (r) that oscillated between 0.58 and 0.73 across orchards. The results showed significance in the rootstock effects for four complex harvest and quality traits (i.e., total number of fruits, number of fruits with exportation quality, and number of fruits discarded because of low weight or thrips damage), whereas the only morphological trait that had a significant heritability value was overall trunk height (an emergent property of the rootstock–scion interaction). These findings suggest the inheritance of rootstock effects, beyond root phenotype, on a surprisingly wide spectrum of scion traits in “Hass” avocado. They also reinforce the utility of polymorphic SSRs for relatedness reconstruction and genetic prediction of complex traits. This research is, up to date, the most cohesive evidence of narrow-sense inheritance of rootstock effects in a tropical fruit tree crop. Ultimately, our work highlights the importance of considering the rootstock–scion interaction to broaden the genetic basis of fruit tree breeding programs while enhancing our understanding of the consequences of grafting.

High-throughput sequencing (HTS) technologies became a powerful approach to generate genomic resources in non-model tree species and to assist breeding programs. These technologies are being used in native forest trees of Argentina and this chapter summarizes the state-of-the-art knowledge. A brief description of the HTS technologies is followed by general applications of HTS on forest trees for genomic resources development and massive genotyping. Genomic strategies to accelerate tree breeding includes genome-wide association studies and genomic selection. HTS technologies were applied to Argentina’s native tree species for transcriptome and genome sequencing of Nothofagus species and transcriptome sequencing of Prosopis alba and Cedrela balansae. Ongoing HTS projects include the transcriptome sequencing of Austrocedrus chilensis, Handroanthus impetiginosus and Cordia trichotoma; the genome sequencing of Austrocedrus chilensis and the transcriptome sequencing of Nothofagus alpina and N. obliqua under drought stress conditions. Current and future genetic studies on native forest tree species and implications for breeding are discussed.

Grafting is typically utilized to merge adapted seedling rootstocks with highly productive clonal scions. This process implies the interaction of multiple genomes to produce a unique tree phenotype. Yet, the interconnection of both genotypes obscures individual contributions to phenotypic variation (i.e. rootstock-mediated heritability), hampering tree breeding. Therefore, our goal was to quantify the inheritance of seedling rootstock effects on scion traits using avocado (Persea americanaMill.) cv. Hass as model fruit tree. We characterized 240 rootstocks from 8 avocado cv. Hass orchards in three regions of the province of Antioquia, in the northwest Andes of Colombia, using 13 microsatellite markers (simple sequence repeats – SSRs). Parallel to this, we recorded 20 phenotypic traits (including morphological, eco-physiological, and fruit yield and quality traits) in the scions for three years (2015–2017). Relatedness among rootstocks was inferred through the genetic markers and inputted in a ‘genetic prediction’ model in order to calculate narrow-sense heritabilities (h2) on scion traits. We used three different randomization tests to highlight traits with consistently significant heritability estimates. This strategy allowed us to capture five traits with significant heritability values that ranged from 0.33 to 0.45 and model fits (R2) that oscillated between 0.58 and 0.74 across orchards. The results showed significance in the rootstock effects for four complex harvest and quality traits (i.e. total number of fruits, number of fruits with exportation quality, and number of fruits discarded because of low weight or thrips damage), while the only morphological trait that had a significant heritability value was overall trunk height (an emergent property of the rootstock-scion interaction). These findings suggest the inheritance of rootstock effects, beyond root phenotype, on a surprisingly wide spectrum of scion traits in ‘Hass’ avocado. They also reinforce the utility of SSR markers for relatedness reconstruction and genetic prediction of complex traits. This research is, up to date, the most cohesive evidence of narrow-sense inheritance of rootstock effects in a tropical fruit tree crop. Ultimately, our work reinforces the importance of considering the rootstock-scion interaction to broaden the genetic basis of fruit tree breeding programs, while enhancing our understanding of the consequences of grafting.

Pedigree reconstruction via DNA markers and subsequent quantitative genetic analyses in production stands of trees is an alternative to traditional forest tree breeding. The method requires variable DNA markers; preferably cost-efficient to genotype. We tested the approach in breeding for Christmas tree traits in a Danish landrace of Abies procera. Initial analysis with simple sequence repeats (SSRs) revealed a substantial reduction in genetic diversity of Danish A. procera compared with direct imports from the USA, indicating a genetic bottleneck. Due to the reduced genetic variation, the SSRs were not variable enough for pedigree reconstruction, and 145 single nucleotide polymorphisms (SNPs) were therefore identified and genotyped via high-throughput targeted sequencing. In the field, we phenotypically selected 674 superior trees, based on criteria for good Christmas trees, among 21,000 trees in three Christmas tree plantations originating from an A. procera clonal seed orchard. By SNP-genotyping and parentage analysis, pedigree was reconstructed for the selected individuals, and genetic predictions for the Christmas tree traits were estimated. A final selection of 45 trees out of the 674 genotyped, based on an index of predicted values for different traits, foresees a gain in the Christmas tree score and branch angle score of 16% and 10%, respectively. The study clearly demonstrated the benefits of pedigree reconstruction, even though mass selection seemed to give similar gain. Primarily, the possibilities to control the level of inbreeding, and to check whether the production stands, from where we select trees, actually originate from the declared and desired parent pool.

A bstract. Loblolly pine is an economically important timber species in the United States, with almost 1 billion seedlings produced annually. The most significant disease affecting this species is fusiform rust disease, caused by the fungus, Cronartium quercuum f.sp. fusiforme. The breeding and deployment of disease resistant families has proven to be a successful strategy for combating rust. Testing for fusiform rust resistance in the greenhouse environment involves artificial inoculations carried out at the USDA Forest Service Resistance Screening Center in Asheville, North Carolina. Disease incidence is determined through visual inspection. However, an automated, high-throughput phenotyping method will improve both the efficiency and accuracy of the disease screening process. This study investigates the use of hyperspectral imaging for screening loblolly pine seedlings for fusiform rust resistance in the greenhouse environment. A nursery trial containing families with known in-field rust resistance data was created, and the seedlings were artificially inoculated with fungal spores. Hyperspectral images using a visible near infra-red camera were collected before inoculation, and regular scans were collected at approximately monthly intervals post-inoculation. Additionally, the disease incidence for all plants was scored with traditional methods based on visible stem galls. The hyperspectral images were segmented from the background using spectral methods, and algorithms were developed for discriminating stem pixels from needle pixels using both spectral and spatial features. Statistical discrimination models were built for classifying seedling scans into diseased and non-diseased classes. A classification model built using stem spectra was found to be more accurate compared to the model built using needle spectra.

In Northern Europe, climate change may facilitate the prevalence of Scots pine, yet also promote the spread of pathogens attacking this species. A common biotic risk for Scots pine in nurseries and young stands is Lophodermium needle cast, primarily caused by Lophodermium seditiosum, which negatively affects the survival and growth of saplings. Reduced tree growth has been observed several years after damage by Lophodermium needle cast. However, for decision-making in protection or resistance breeding, an estimate of financial loss is important. Thus, the study aimed to assess the long-term influence of Lophodermium needle cast on the growth and financial value of Scots pine stands. The effect of needle cast damage during the sixth growing season on growth at the age of 17 years was evaluated in a control-crossed Scots pine progeny trial, and the results indicated a significantly negative effect on the height and diameter of the trees. A significant family effect also existed on the severity of the needle cast damage. Long-term simulations indicated that severely damaged Scots pines had a reduced equivalent annual annuity (EAA) of almost 100% at the final harvest. More intensive early management to reduce stand density could partly compensate for losses caused by needle cast. A higher EAA for the most resistant group of trees regardless of the stand management scenarios suggests an economically justified potential for improved resistance. Strong negative (&minus, 0.62 to &minus, 0.70) correlations of height and survival with the proportion of severely affected trees at the family mean level implies that resistant genotypes can be selected along with improved growth in progeny trials, which are affected by needle cast.

Made available in DSpace on 2020-12-11T11:00:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-15 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Corymbia citriodora is one of the most cultivated hardwood species by small farmers in Brazil, and the most traded wood on the east coast of Australia due its high growth rate combined with high wood density. The study of genotype-by-environment interaction (GEI) is one of the most critical elements in the management of a breeding program to define breeding zones and to select genetic material targeted to specific environmental conditions. The aim of this research was to estimate genetic parameters in a C. citriodora progeny tests, established using 56 open-pollinated families in three sites with contrasting soil texture within the Luiz Antonio's experimental station, Brazil. The following traits were measured at 30 years of age: total height, diameter at breast height (DBH), stem form and survival. Based on this data, the individual volume was estimated. The harmonic mean relative performance of genetic values (MHPRVG) predicted by BLUP was used to evaluate productivity, stability and adaptability. The GEI was found to be not significant in all growth traits. A complex GEI was detected only for survival, supporting the importance of choosing the right genetic material of the species to specific sites. The present analysis showed a significant difference between families for DBH, survival and volume. In summary, the material studied presents potential to obtain attractive genetic gains through selection. However, in order to keep these sustained gains over the next selection cycles it is necessary to incorporate new genetic materials in order to increase genetic diversity. Univ Fed Sao Carlos, Km 110 Joao Leme dos Santos, BR-18052780 Sorocaba, SP, Brazil Inst Florestal Sao Paulo, Rua Horto 931, BR-02377000 Sao Paulo, Brazil Univ Florida, Sch Forest Resources & Conservat, Gainesville, FL 32601 USA Univ Fed Mato Grosso do Sul, Cidade Univ,Caixa Postal 549, BR-79002970 Campo Grande, Mato Grosso, Brazil Univ Estadual Paulista, Fac Engn Ilha Solteira, Ave Brasil 56, BR-15385000 Sao Paulo, Brazil Univ Fed Amazonas, Av Gen Rodrigo Octavio Jordao Ramos 1200, BR-69067005 Manaus, Amazonas, Brazil Univ Estadual Paulista, Fac Ciencias Agron, BR-18610307 Botucatu, SP, Brazil Embrapa Floresta, Km 111,Estr Ribeira,POB 319, BR-83411000 Colombo, Parana, Brazil Univ Estadual Paulista, Fac Engn Ilha Solteira, Ave Brasil 56, BR-15385000 Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agron, BR-18610307 Botucatu, SP, Brazil CAPES: 1615329

Cedrela odorata, conocida comúnmente como cedro rojo, es una especie forestal tropical de alto valor comercial en el mercado internacional de la madera. La fragmentación del paisaje en su área de distribución y la tala clandestina con selección disgénica causan erosión genética en sus poblaciones naturales, lo que disminuye su potencial adaptativo y productivo. Debido a esto, es más susceptible a daños por factores abióticos y bióticos como Hypsipyla grandella, su principal plaga y causa de bajo rendimiento en plantaciones comerciales. Es así, que se incluye en las listas de organizaciones internacionales como IUCN y CITES, y en México es protegida por la NOM-059 SEMARNAT-2010; sin embargo, la falta de suficientes evidencias sobre su riesgo real pone en duda su permanencia en esta última. Por ello, aunque se han realizado algunas investigaciones para determinar su diversidad genética en poblaciones de América Central, cariotipo, caracterización de su plastoma y transcriptoma foliar, aún falta información esencial para su manejo eficiente y sostenible. El objetivo de la presente revisión es proporcionar un panorama del conocimiento existente sobre los recursos genéticos de cedro rojo, con el fin de identificar alternativas basadas en herramientas biotecnológicas que permitan la comprensión de la especie y fundamenten el diseño e implementación de programas de mejoramiento genético y conservación a largo plazo.

Sustainable and efficient forestry in a rapidly changing climate is a daunting task. The sessile nature of trees makes adaptation to climate change challenging; thereby, ecological services and economic potential are under risk. Current long-term and costly gene resources management practices have been primarily directed at a few economically important species and are confined to defined ecological boundaries. Here, we present a novel in situ gene-resource management approach that conserves forest biodiversity and improves productivity and adaptation through utilizing basic forest regeneration installations located across a wide range of environments without reliance on structured tree breeding/conservation methods. We utilized 4,267 25- to 35-year-old European larch trees growing in 21 reforestation installations across four distinct climatic regions in Austria. With the aid of marker-based pedigree reconstruction, we applied multi-trait, multi-site quantitative genetic analyses that enabled the identification of broadly adapted and productive individuals. Height and wood density, proxies to fitness and productivity, yielded in situ heritability estimates of 0.23 ± 0.07 and 0.30 ± 0.07, values similar to those from traditional "structured" pedigrees methods. In addition, individual trees selected with this approach are expected to yield genetic response of 1.1 and 0.7 standard deviations for fitness and productivity attributes, respectively, and be broadly adapted to a range of climatic conditions. Genetic evaluation across broad climatic gradients permitted the delineation of suitable reforestation areas under current and future climates. This simple and resource-efficient management of gene resources is applicable to most tree species.