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One of the major goals of modern agriculture is to achieve increased crop yield using less water. Despite significant advancements in genomics, an efficient phenotypic characterization remains indispensable for the success of modern breeding programs aiming to expedite genetic gains through early-stage selection deployment. Thus, this study aimed to identify which traits are most important to discriminate the maize genotypes to support early selection under contrasting water availability conditions. For this, we used a public diversity panel of 360 tropical maize inbred lines, involving two conditions, well-watered (WW) and water-stress (WS) across eight trials. Evaluations were carried out in the phenological stage V6 for shoot and root traits. There was a significant variation in the panel performance, mainly for root traits under WS conditions, composing six clusters. Notably, clustering patterns based on principal components were similar under WW and WS conditions. A strong correlation was found among roots length, surface area, and volume, allowing the exclusion of more error-prone traits. Redundancy analysis (RDA) highlighted plant height, stalk diameter, and lateral roots length as the most sensitive traits to WS, suggesting their utility in early selection for water-use efficiency in maize breeding programs. [ABSTRACT FROM AUTHOR]

Cross breeding is an important way to innovate germplasm. However, the growth performance of hybrid offspring is difficult to predict. Pinus yunnanensis is an important tree species for both timber and industrial raw materials in southwest China, and its genetic degradation is a serious concern. To accelerate the breeding process and diversify the genetic resources, 16 interspecific crosses of P. yunnanensis × P. kesiya and 22 intraspecific crosses of P. yunnanensis were evaluated and selected based on the systematic analysis of nutritional and reproductive growth traits. The results indicated that the differences in traits between the different combinations were significant, suggesting that the interspecific and intraspecific hybrid offspring showed high genetic variation with potential for selection. The interspecific crosses were considerably better than the intraspecific crosses for all phenotypic traits, indicating that the distant hybridization had an advantage of heterosis. Compared with the open-pollinated progeny, the progeny of superior hybrid family significantly improved in nutritional growth traits, and declined in reproductive growth traits. The coefficients of phenotypic variation, genetic variation, family heritability and individual heritability for the phenotypic traits were higher than other Pinus, indicating that the traits were highly variable and under strong genetic control. Nutritional and reproductive growth traits could be selected independently. Five interspecific crosses and one intraspecific cross were selected using a combination of the membership function and an independent selection method. Our findings provided an important material basis and theoretical support for hybrid breeding and genetic improvement of Pinus. [ABSTRACT FROM AUTHOR]

In common beans (Phaseolus vulgaris L.), upright plant architecture is highly valued for agriculture. As plant architecture is controlled by many genes, recurrent selection is the optimal strategy for breeding programs. Additionally, conducting mass selection before flowering to intercross selected plants in the field increases efficiency by reducing the number of harvests to complete a selective cycle. For this to be effective, the plant's architecture at flowering must accurately predict its trait at harvest. Based on that, the objective of this study was to verify whether there is an association between plant architecture at flowering and at harvest and to study the relationship between plant architecture traits and grain yield. The traits assessed were plant height and plant architecture scores at flowering and harvest, stem diameter, grain yield, and the mass of hundred grains. Sixty-two progenies from each S0:2, S0:3 and S0:4 generations, with two commercial cultivars, were evaluated across three environments in a triple lattice experimental design. Genetic and phenotypic parameters and correlation coefficient were estimated. Progenies selection was carried out using index Z, and subsequently, the correlated response in the traits was determined. It was found that the correlation between heights and architecture scores at flowering and harvest were of high magnitude (r ≥ 0.90). There was also a low correlation between plant architecture traits and grain yield (− 0.29 < r ≤ 0.03). The results of this study suggest that selecting upright plants during the flowering stage is feasible, and that plant architecture and grain yield are expressed independently. [ABSTRACT FROM AUTHOR]

Key message: Understanding bark allocation in juvenile stages of commercially viablePinustrees can be useful in dating wood formation, thus improving the accuracy of correlating wood quality to environmental factors. Bark is an important and multifunctional part of plant anatomy that has been researched mostly in the context of fire history, timber resource assessments and more recently as a bioresource. Few studies have comprehensively examined bark thickness in some commercially valuable Pinus species. More importantly, the role of bark in accurately dating wood formation has seldom been researched. This study was conducted to model and compare bark thickness variation between different species of young South African-grown Pinus trees including Pinus radiata var. radiata D. Don., Pinus elliottii Engelm., Pinus elliottii × Pinus caribaea var. hondurensis, Pinus patula × Pinus tecunumanii (Low Elevation), and Pinus patula × Pinus tecunumanii (High Elevation). Measurements were taken at 1.6 and 2.3 years including absolute and relative bark thickness and distribution along the stem. Results showed species-specific variation in absolute and relative bark thickness with the highest means recorded in Pinus elliottii × Pinus caribaea and lowest in Pinus radiata. A positive linear relationship was observed between bark thickness and diameter, consistent with all species and ages. Absolute bark thickness decreased along the stem from bottom to top while more nuanced patterns of variation were observed for relative bark thickness. These findings underscore the importance of understanding bark thickness in young trees for various applications, including dating wood formation, anticipatory breeding strategies for quality wood and predicting stand quality among others. [ABSTRACT FROM AUTHOR]

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Sitka spruce (Picea sitchensis (Bong.) Carr.), is a highly valuable commercial tree species in Ireland, UK and elsewhere in Europe but there is relatively little information available in relation to the performance of improved material. The primary objective of this study was to explore the genetic variation in competitive ability and determine how a spatial model improved the accuracy of genetic estimates over time for Sitka spruce. To achieve this, the study employed competition index (Hegyi's I) and spatial analysis on height and diameter data from genetic improvement trials in Ireland. A total of 54 half-sib families of Sitka spruce were included in the study. The trials had been established to identify superior genotypes among the plus trees which had been included in the improvement programme in Ireland. The study revealed that spatial heterogeneity significantly affects the genetic estimates for Sitka spruce. The results indicated that spatial analysis could provide valuable insights into the genetic trials of Sitka spruce and improve the accuracy of genetic evaluations. Heritability increased by 104% for diameter at breast height (DBH) using a spatial analysis approach, compared with a more traditional non-spatial model approach. It was found that thinning practices can affect the response of genetic performance to spatial heterogeneity. In addition, genetic variation in competitive ability was observed. The results highlight the importance of considering spatial dependence in the design but more importantly in the analysis of genetic trials and provides a framework for future research on the genetic improvement of Sitka spruce populations. [ABSTRACT FROM AUTHOR]

Castanopsis hystrix, a precious tree species in Southeast Asia, has the advantages of rapid growth and high-quality wood materials. However, there are problems such as its long breeding cycle and low efficiency, and being time-consuming, which greatly restricts the industrial development of C. hystrix. Performing genome selection (GS) for growth and wood traits for the early selection of superior progeny has great significance for the rapid breeding of new superior varieties of C. hystrix. We used 226 clones in the main distribution and 479 progenies within 23 half-sib families as experimental materials in this study. Genotyping datasets were obtained by high-throughput re-sequencing technology, and GS studies were conducted on the growth (tree height (H), diameter at breast height (DBH)) and wood (wood density (WD), fiber length (FL), and fiber length–width ratio (LWR)) traits. The coefficient of variation (CV) of five phenotypic traits ranged from 10.1% to 22.73%, the average CV of growth traits was 19.93%, and the average CV of wood traits was 9.72%. The Pearson correlation coefficients between the five traits were almost all significantly positive. Based on the Genomic Best Linear Unbiased Prediction (GBLUP) model, the broad-sense heritabilities of growth traits were higher than those of wood quality traits, and the different number of SNPs had little effect on the heritability estimation. GS prediction accuracy first increased and then reached a plateau at around 3K SNPs for all five traits. The broad-sense heritability of these five traits was significantly positively correlated with their GS predictive ability (r = 0.564, p < 0.001). Bayes models had better GS prediction accuracy than the GBLUP model. The 15 excellent progeny individuals were selected, and their genetic gain ranged from 0.319% to 2.671%. These 15 superior offspring individuals were 4388, 4438, 4407, 4468, 4044, 4335, 4410, 4160, 4212, 4461, 4052, 4014, 4332, 4389, and 4007, mainly from three families F5, F6, and F11. Our research lays out the technical and material foundation for the rapid breeding of new superior varieties of C. hystrix in southern China. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum f. sp. lentis (Fol) is considered the most destructive disease for lentil (Lens culinaris Medik.) worldwide. Despite the extensive studies elucidating plants' metabolic response to fungal agents, there is a knowledge gap in the biochemical mechanisms governing Fol-resistance in lentil. Τhis study aimed at comparatively evaluating the metabolic response of two lentil genotypes, with contrasting phenotypes for Fol-resistance, to Fol-inoculation. Apart from gaining insights into the metabolic reprogramming in response to Fol-inoculation, the study focused on discovering novel biomarkers to improve early selection for Fol-resistance. GC-MS-mediated metabolic profiling of leaves and roots was employed to monitor changes across genotypes and treatments as well as their interaction. In total, the analysis yielded 178 quantifiable compounds, of which the vast majority belonged to the groups of carbohydrates, amino acids, polyols and organic acids. Despite the magnitude of metabolic fluctuations in response to Fol-inoculation in both genotypes under study, significant alterations were noted in the content of 18 compounds, of which 10 and 8 compounds referred to roots and shoots, respectively. Overall data underline the crucial contribution of palatinitol and L-proline in the metabolic response of roots and shoots, respectively, thus offering possibilities for their exploitation as metabolic biomarkers for Fol-resistance in lentil. To the best of our knowledge, this is the first metabolomics-based approach to unraveling the effects of Fol-inoculation on lentil's metabolome, thus providing crucial information related to key aspects of lentil–Fol interaction. Future investigations in metabolic aspects of lentil–Fol interactions will undoubtedly revolutionize the search for metabolites underlying Fol-resistance, thus paving the way towards upgrading breeding efforts to combat fusarium wilt in lentil. [ABSTRACT FROM AUTHOR]

Water stress is considered one of the main environmental factors that limit survival and productivity of Eucalyptus plantations. Identifying genotypes traits that provide evidence of tolerance to water stress may allow sustained productivity and secure better resilience of forest plantations under climate change in Mediterranean environments. Our study analyzed morphological, physiological, and carbon (C) balance responses of ten Eucalyptus genotypes under contrasting water regimes under nursery conditions. One-year-old cuttings of Eucalyptus nitens (En1 and En2), E. smithii (Es), E. badjensis (Eb), E. nitens x globulus (Eng1, Eng2, Eng3, and Eng4), E. globulus (Eg), and E. camaldulensis x globulus (Ecg) were evaluated under progressive drought from well-watered (soil water potential close to 0 MPa) to severe water stress (soil water potential close to − 2.5 MPa) conditions. Absolute growth rate (root collar diameter, height, shoot: root biomass ratio), net photosynthesis, stomatal conductance, transpiration, intrinsic water use efficiency (iWUE), predawn water potential (Ψpd) and C balance (flux and partitioning) were evaluated. As expected, water stress significantly reduced growth and physiological activity for all genotypes. Of all evaluated parameters iWUE and Ψpd were the key grouping physiological and growth response variables among genotypes. Genotypes En1, Eng3, and Eng4 were considered tolerant genotypes, with the smallest physiological change and larger morphological growth. Genotypes En2, Es, Eng1 and Eng2 were moderately tolerant showing intermediate responses compared to other groups. In contrast, Eg, Eb, and Ecg were considered highly sensitive, with major changes in morphology and physiological variables over time. Our results suggest that nursery stage physiological evaluation of genotypes may allow selection for sites with water resource availability risks and may allow to reduce mortality and early establishment productivity losses under drier climate change scenarios. [ABSTRACT FROM AUTHOR]

The ecological significance of Scots pine (Pinus sylvestris L.) in Europe, especially in areas devastated by bark beetles, has led to its consideration as a substitute for Norway spruce. This pioneering species boasts sun and drought tolerance, fast growth, and wood industry value. To gauge its potential, we examined two ecotypes across two test sites over two years, focusing on height and growth increment. Through statistical analysis employing R software and linear mixed models, we assessed heritability, genotype by environment interaction, and spatial correlations. Both ecotypes exhibited significant differences in height and increment, varying by year and site. Heritability was higher in the second year, with increment showing greater stability. Genetic correlations between sites were evident, suggesting stable increment ranking across locations. These findings underscore the role of ecotypic variation in Scots pine growth, advocating for its consideration in reforestation. Acknowledging such dynamics is vital for effective forest management and reforestation in Central Europe, promoting sustainability and informed decision-making. Further research will enhance this understanding of preserving and enhancing the region's tree populations.

The ecological significance of Scots pine (Pinus sylvestris L.) in Europe, especially in areas devastated by bark beetles, has led to its consideration as a substitute for Norway spruce. This pioneering species boasts sun and drought tolerance, fast growth, and wood industry value. To gauge its potential, we examined two ecotypes across two test sites over two years, focusing on height and growth increment. Through statistical analysis employing R software and linear mixed models, we assessed heritability, genotype by environment interaction, and spatial correlations. Both ecotypes exhibited significant differences in height and increment, varying by year and site. Heritability was higher in the second year, with increment showing greater stability. Genetic correlations between sites were evident, suggesting stable increment ranking across locations. These findings underscore the role of ecotypic variation in Scots pine growth, advocating for its consideration in reforestation. Acknowledging such dynamics is vital for effective forest management and reforestation in Central Europe, promoting sustainability and informed decision-making. Further research will enhance this understanding of preserving and enhancing the region's tree populations. [ABSTRACT FROM AUTHOR]

Cultivated potato varieties are tetraploid and vegetatively propagated. Therefore genetic improvement for new traits is less effective through hybridization. The mutation is considered an alternative method for crop improvement of those varieties. This study aimed to evaluate the effects of gamma-ray irradiation on increasing genetic diversity among the somaclones and the changes in population structure. Forty-four somaclones were used as observed materials. The population was grown in a screen house using a completely randomized design with genotype (somaclone) as a single factor. Thirteen qualitatively and quantitatively morphological characters were observed. Six SSR markers were used for analyzing the population structure. The selection process was based on a weighting method divided into quartiles. Selected numbers were taken from quartile 3. Morphological analysis of stems and leaves resulted in five different somaclones, with significant differences in anthocyanin appearance and intensity of the green color of the leaflets. Diversity criteria based on quantitative characteristics showed a high level of diversity with a high heritability for tuber weight, length, and diameter and a moderate heritability for tuber number. Analyzing the population structure has offered insight into how gamma irradiation affected the somaclones. As a result of the selection, 12 somaclones met the requirements to serve as seed sources for field testing. It is expected that the results of this study will provide information about the diversity caused by gamma-ray irradiation treatment on potato somaclones and a method for improving the efficiency of the initial selection of potato populations. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of this study was to verify the repeatability of the expression of forage characters in intraspecific hybrids of Paspalum notatum Flügge to aid early selection. Across five harvests, plant height, tiller population density, leaf dry matter, stem dry matter, inflorescence dry matter, total dry matter, and growth habit were quantified for five parents, 189 hybrids, and a commercially available cultivar as a control (n = 195). Analysis of variance, principal components analysis, and structural analysis methods were used to determine the repeatability coefficients. The repeatability coefficients ( ρ ^) for all evaluated characteristics generated by the different methods were between 0.05 (ANOVA II) and 0.95 (PCACov). For most of the characteristics studied, repeatability coefficients and determination coefficients were considered high. The repeatability coefficients estimates obtained for the eight characteristics evaluated with the ANOVA I and II methods were almost always lower than those obtained by PCA and structural analysis methods. Based on the covariance matrix, the principal component method generated higher estimates than those produced by ANOVA or structural analysis. Assuming a minimum 80% reliability to verify the relative superiority of the hybrids across all assessed traits, the five harvests proved adequate for selecting the optimal plant materials to advance to the next phase of the breeding program. However, reliable early selection for leaf dry matter, leaf:stem ratio, and total dry matter required a minimum of two harvests. The genetic parameters (h2 and CVg) showed a favorable scenario for direct selection to increase forage production.

This study aimed to apply selection indexes in situations in which F2 populations and their parents are evaluated simultaneously in field trials to predict population genotypic values and selecting the best populations. Fifteen F2 soybean populations were evaluated for number of days to flowering and to maturity and grain yield. The data was analyzed using restricted maximum likelihood/best linear unbiased prediction (REML/BLUP) to obtain genotypic effects, variance components and accuracies. Four selection methods were compared: genotypic values of the F2 populations (gF2), combined index with the mean genotypic value of parents and F2 population (Ia) and two indexes that add (to gF2 and to Ia) and consider genetic variability within populations (Ib and Ic). The index Ia presented a result similar to that obtained with the gF2 selection method. Selection indexes (Ib and Ic) based on several sources of information were more efficient than selection based on gF2 values only. [ABSTRACT FROM AUTHOR]

Larix gmelinii var. principis-rupprechtii (Mayr.) Pilger is an important native tree species in North China with advantages of fast growth, straight trunk, and good wood properties. The multi-year and multi-site breeding research of families of the species has not been reported previously. Based on diameter at breast height (DBH), height and volume of 25 families on four experimental sites, we calculated variance components, genetic parameters, juvenile and mature trait correlations and made genotype main effect plus genotype × environment interaction effect (GGE) biplot based on the breeding values estimated using the method of best linear unbiased prediction (BLUP). Compared with height, DBH and volume had higher heritability and larger variation coefficients, making them the more suitable traits for family selection and evaluation. Based on these, GGE biplots containing 20 combinations of site × age were drawn using data at 13 to 17 years when the interactions between family and location were strong. Test sites classifications based on DBH, and volume were inconsistent, with two categories for DBH and one for volume. The Guyuan site was the most suitable with strong discriminating ability, high representativeness and stability among tree ages. Integrating the ranking results of DBH and volume, families 66, 76, 82 and 111 were high-yielding and stable, families 78 and 96 were high-yielding with above average stability, families 72 and 79 were high-yielding with below average stability, whereas stability of family 100 was inconsistent between DBH and volume. Early selection based on DBH was convenient and reliable, and can be made at seven years. This study provides support for the selection of Larix gmelinii var. principis-rupprechtii families in Hebei province and an example for the application of stem analysis data from multiple sites in tree breeding. [ABSTRACT FROM AUTHOR]

Eucalyptus tereticornis exhibits adaptation to a wide range of soils and environments, making it suitable for various protective and productive purposes throughout the territory of Uruguay. Due to the absence of a locally improved seed source, INIA began a tree breeding program in 2007 using genetic material from two sources: the natural distribution area of the species and local plantations. The performance of the genetic pool was evaluated at different sites over a nine-year growth period. The objectives of this study were to estimate genetic parameters (heritability, genetic correlations, and genotype-by-environment interaction) for growth and stem form traits and to estimate the genetic gains achievable through selection at different ages, in order to guide the breeding strategy for E. tereticornis. The genotype-environment interaction for volume and survival exhibited moderate to low levels, with Type B genetic correlations ranging from 0.68 to 0.82. The combined analysis of the trials revealed that heritability increased with the age of measurement for all traits, with values ranging from low to moderate for growth variables (0.04 - 0.23) and stem form (stem straightness and forking) showing low values (0.05 - 0.12). Genetic correlations between growth traits at different ages and volume at 9 years were positive and high (0.32 - 0.99), while the correlations between stem form (stem straightness and forking) and volume were low to moderate (0.30 - 0.56). The results obtained suggest that it is possible establish a single breeding unit and that through early selection, genetic gains can be maximized, evaluation costs reduced, and improved seed obtained in a shorter timeframe. [ABSTRACT FROM AUTHOR]

Genomic selection (GS) is currently being used in the New Zealand radiata pine (Pinus radiata D. Don) breeding program to accelerate genetic gain. GS also has the potential to accelerate the deployment of genetic gain to the production forest through early selection. The increased rate of genetic gain in the breeding cycle will need to be transferred more quickly to realise that gain in the deployment population. GS selections will have lower accuracies than selections based on phenotypic data as currently practised; however, it is unknown how this will affect the genetic gain from GS-based deployment. Moreover, census size and turnover rate need to be optimised to cope with the influx of new marker-based selected material into a commercial orchard. We utilised a stochastic simulation approach to investigate these concepts, comparing three deployment scenarios: half-sib open-pollinated orchards (OP), full-sib control-pollinated orchards (CP) and clonal deployment through somatic embryogenesis. When accounting for time, genomic selection in OP, CP and clonal deployment pathways increased genetic gain by 9.5%, 15.9% and 44.6% respectively compared to phenotypic selection. The optimal orchard scenario would be genomic-selected control-pollination with a low census size (n = 40, males and females combined), low female turnover (5%) and a high male turnover (15–25%). This scheme balances high genetic gain with high seed yield while moderating the rate of inbreeding. [ABSTRACT FROM AUTHOR]

The development process of a new wheat cultivar requires time between obtaining the base population and selecting the most promising line. Estimating genetic parameters more accurately in early generations with a view to anticipating selection means important advances for wheat breeding programs. Thus, the present study estimated the genetic parameters of F2 populations of tropical wheat and the genetic gain from selection via the Bayesian approach. To this end, the authors assessed the grain yield per plot of 34 F2 populations of tropical wheat. The Bayesian approach provided an adequate fit to the model, estimating genetic parameters within the parametric space. Heritability (h² ) was 0.51. Among those selected, 11 F2 populations performed better than the control cultivars, with genetic gain of 7.80%. The following populations were the most promising: Tbio Sossego/CD 1303, CD 1303/Tbio Ponteiro, BRS 254/CD 1303, Tbio Duque/Tbio Aton, and Tbio Aton/CD 1303. Bayesian inference can be used to significantly improve tropical wheat breeding programs. [ABSTRACT FROM AUTHOR]

In previous works, a method was developed for the differentiation at the foliar level of the response of banana plants to Fusarium race 1 wilt, which constitutes a useful tool to increase the efficiency of resistance selection in ex vitro conditions. The objective of this work was to evaluate resistance to this disease in new banana clones using the evaluation method mentioned. For this, six moments of evaluation were made; and ten plants of each selected line of the irradiated 'Zanzíbar' clone were used. The results showed that the plants of the evaluated lines of the irradiated 'Zanzíbar' clone indicate that they are promising materials for genetic improvement in the crop aimed at resistance to this disease. On the other hand, a response to selection was obtained in a short time (48 hours), as well as evaluating the lines selected from large populations of plants (60 plants) with the exclusion of other organisms; and the control of environmental conditions that could interfere with the results obtained. However, it is necessary to continue additional studies in the field to confirm the resistance in the evaluated lines. [ABSTRACT FROM AUTHOR]

The identification of genotypes more tolerant to water deficit is a challenge to breeding programs. In this research, our objectives were to identify and validate traits for tolerance to water deficit in eucalypts. The estimation of genotypic parameters and early selection are proposed based on mixed models, selection indexes and validation schemes. Seedlings with 110 days were grown in a greenhouse for 12 weeks, and two water deficit treatments were conducted (polyethylene glycol and water limitation). A total of 26 biomarkers were evaluated, and 15 of them were significant, exhibited adequate heritability, and used for screening: final plant height, increment in height, increment in diameter, area of mature and fully expanded leaf, nutrient contents of N, K, Ca, Mg, S, Cu, Zn, Mn and B, photosynthesis (A) and stomatal conductance (gs). Both treatments were adequate to discriminate water deficit-tolerant clones. The ranking of tolerant clones according to their phenotype in the field demonstrates the potential for early selection and is consistent with the maintenance of water-deficit-tolerance mechanisms until adulthood. There is evidence that the choice of biomarker depends on the species involved and different strategies contributing to the tolerance trait. [ABSTRACT FROM AUTHOR]

The objective of the study was to determine whether Parkia platycephala families with superior morphophysiological traits perform consistently across four stages of early development (plantlets, seedlings, and juveniles at 34 and 60 months), as a means to assess the possibility of conducting preselection. For 21 morphophysiological traits, the following genetic parameters were estimated: heritability, coefficients of variation (genetic, relative, and environmental), accuracy, genetic and phenotypic correlation, percentage of coincidence (PC) of the best families, effective population size, and inbreeding in three progeny tests conducted under laboratory, nursery, and field conditions. Families of P. platycephala showed significant phenotypic and genotypic differences. The traits evaluated show genetic control. The percentage of coincidence between the best families was more accurate when the selection intensity was greater than 50% (PC ≥ 52%). Based on the evaluated traits, a pre-selection strategy at the juvenile stage for P. platycephala was researched to effectively identify superior families. [ABSTRACT FROM AUTHOR]

Brain sensory processing is not passive, but is rather modulated by our internal state. Different research methods such as non-invasive imaging methods and intracranial recording of the local field potential (LFP) have been used to study to what extent sensory processing and the auditory cortex in particular are modulated by selective attention. However, at the level of the single- or multi-units the selective attention in humans has not been tested. In addition, most previous research on selective attention has explored externally-oriented attention, but attention can be also directed inward (i.e., internal attention), like spontaneous self-generated thoughts and mind-wandering. In the present study we had a rare opportunity to record multi-unit activity (MUA) in the auditory cortex of a patient. To complement, we also analyzed the LFP signal of the macro-contact in the auditory cortex. Our experiment consisted of two conditions with periodic beeping sounds. The participants were asked either to count the beeps (i.e., an "external attention" condition) or to recall the events of the previous day (i.e., an "internal attention" condition). We found that the four out of seven recorded units in the auditory cortex showed increased firing rates in "external attention" compared to "internal attention" condition. The beginning of this attentional modulation varied across multi-units between 30-50 msec and 130-150 msec from stimulus onset, a result that is compatible with an early selection view. The LFP evoked potential and induced high gamma activity both showed attentional modulation starting at about 70-80 msec. As the control, for the same experiment we recorded MUA activity in the amygdala and hippocampus of two additional patients. No major attentional modulation was found in the control regions. Overall, we believe that our results provide new empirical information and support for existing theoretical views on selective attention and spontaneous self-generated cognition. [ABSTRACT FROM AUTHOR]

The potential effects of climate change plus the expansion of eucalypt plantations to less favorable sites, beyond those where they are currently planted, requires exploring novel eucalypt germplasm to identify taxa less vulnerable to biotic and abiotic stress. To improve plant adaptation to new environments, the first step is breeding programs and/or forming base populations of new and different species. But, to achieve this, what species should be chosen from the almost 1000 existing eucalypt species? To tackle this question, this work evaluated various eucalypt species from different provenances at two assessment in five environments to verify (1) the need for environmental stratification; (2) the best species and provenances per environment, and (3) environmental stability, adaptability, and changes between assessment. The mortality and diameter at breast height of 27 eucalypt taxa originating from wild populations and seed orchards were evaluated. To evaluate the data, we took a factor analytic mixed modelling approach to define mega-environments (groups of similar sites) and characterize the interactions of these with the selected taxa. The analyses allowed both quantitative and graphical identification of optimal combinations of species and sites. Promising taxa identified include Corymbia citriodora subsp. variegata, C. henryi, Eucalyptus longirostrata, E. major and E. urophylla. We place the results of this process in the context of ongoing domestication and breeding of new taxa for challenging sites in Brazil. [ABSTRACT FROM AUTHOR]

Scientific knowledge through studies with fundamental and applied research has revolutionized plant breeding over the past decades. Given the importance of the fruits for their nutritional, health, and industrial value, the apricot breeding programs evolved continuously. The integrated use of actual gene banks, multiple crossings, selection, and the use of genetic engineering programs lead to improve apricot trees performance. Meanwhile, the production of resistant cultivars to harsh environmental conditions and climate changes, especially to hard winter temperatures and late frosts, disease-resistant, with early maturity, high-quality fruits, and large production is the main objective. This article aims to provide an overview of achievements in the breeding and improving the production of apricot fruits in the world, highlighting the modern challenges in apricot orchards. Recently, digitalization and mechanization can be involved as useful tools in breeding studies and orchard monitoring and management. [ABSTRACT FROM AUTHOR]

Aim of study: To define an early selection strategy based on tests applied to full-sibling progenies of Pinus caribaea var. hondurensis grown in the Cerrado Biome. Area of study: Prata region (MG), Brazil. Material and methods: Progeny tests were cultivated in 2006; the study followed a completely randomized design, with 79 families of full-siblings and 15 repetitions, with one plant per plot. Thinning was carried out at the age of 6 and 8 years; 615 individuals and 44 families were included in the test. The following quantitative variables were used in the statistical analysis of data on the remaining individuals: diameter at breast height (DBH) in cm, total height (H) in m, and volume in dm³ at the age of 3, 4, 5, 6, 7, 8 and 11 years. BLUP multi-trait multivariate model, with non-structured covariance structure matrix, was adopted for calculations. Main results: There were strong additive genetic correlations (above 90%) between variables DBH and H, in all analyzed ages. Strong volume correlations were estimated based on the age group over four years; volume selection efficiency reached its peak at the age of five years. Selection based on volume at the age of 5 years leads to genetic gains in this variable; selection intensity values can range from 7.8% to 6.4% and 5.4%, and from 10% to 20% and 30%. Research highlights: The best strategy lies on carrying out the selections at the age of five years, based on 30% selection intensity.

The increasing concern about ecological impacts of wood preservation chemicals has raised the interest in the natural durability of Scots pine (Pinus sylvestris L.) heartwood. Phenolic compounds—stilbenes—have been found to inhibit fungal growth, making heartwood more resistant to decay. There is a strong genetic component in the stilbene content of the heartwood in Scots pine, with a positive correlation between stilbene content in the heartwood of mother trees and their progenies. Vegetative propagation, i.e., somatic embryogenesis (SE) of Scots pine genotypes with high content of stilbenes could provide a way to produce more durable timber, assuming that there is no trade-off between SE propagation and capacity for high stilbene synthesis. To study this, we made SE initiations from parent genotypes with high and low content of stilbenes in their heartwood, using seed embryos from both open-pollinations and controlled crossings as explants. The success of SE was followed from initiation to embling acclimatization, together with measurements of stilbene content in the explants and the established SE lines. The results show that SE can be induced and emblings regenerated from trees with both high and low content of stilbene. Content of stilbenes was generally low in SE cultures and varied widely among the lines. Following the successful initiation, the later phases of SE propagation proceeded with no connection to the parent genotypes or the stilbene level of the ECs and had large variation among SE-lines. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aimed at determining the optimal number of replications and measurements necessary for the screening of soybean cultivars subjected to three conditions of water availability during the initial stage of development. Two experiments were carried out in a greenhouse. A randomized block design was used, in a factorial scheme with two factors (cultivar and water availability), six replications, ten cultivars and three conditions of water availability (control condition, in which the sand was moistened with water; stress control in the water potential of -0.2 MPa and stress condition in the water potential of -0.4 MPa). At 20 days after cultivation, measurements were taken, subsequently estimating the repeatability coefficient, of the number of necessary measurements and of the determination coefficient. The repeatability coefficient was estimated by distinct statistical procedures, such as method of analysis of variance, principal components with basis on the matrices of phenotypic variances and covariances; principal components with basis on the matrices of correlation and structural analysis. For the determination of the number of replications, the repeatability coefficients ranged from low to high in experiment I, except for the root variables, which presented high values in both experiments. In experiment II, in turn, the magnitudes of the determination coefficients were above 90%. For plant height, number of leaves, root length and dry matter of the aerial part, only two replications would be necessary to obtain 80% confidence. Regarding the number of measurements per parcel, only one plant could be evaluated in each parcel, with 85% confidence for both experiments. Only two replications and one measurement per parcel are enough for high estimates of repeatability. This way, adequate efficiency is obtained in the selection of superior materials for tolerance to water deficit, during the initial stages of soybean development.

Copyright of Argentinian Horticulture / Horticultura Argentina is the property of Revista Horticultura Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] This study investigated the genetic variation of growth traits (DBH, height and volume) of Cunninghamia lanceolata clones at different stand ages and explored suitable age for early selection to provide basis for rebreeding of fine varieties. [Method] A total of 56 samples from 131 C. lanceolata clones were randomly selected from the survey data of individual trees. Based on the data of DBH, height and volume measured at ages of 5,10,15,20 and 30 years, the variation analysis, variance analysis and reduplication estimation of traits were carried out to analyze the genetic variation rule of each clone at different stand ages. Early and late correlation analysis and cluster analysis were also used to determine suitable stand age for early selection. Clustering analysis and Bregkin multi-trait evaluation method were used to select fast growing clones and the selection effect was evaluated by calculating genetic gain and realistic gain. [Result] There were rich variations in DBH, height and volume of C. lanceolata clones, with ranges of 11.82%-24.41%, 10.56% -21.28% and 30.83%-66.73% respectively. They were in the order of volume >DBH>height. The results of variance analysis showed that DBH, height and volume of C. lanceolata were significantly different among clones with repetitions of 0.919 - 0.947. Correlation analysis showed that morning and evening correlations of growth traits were extremely significant and positive with correlation coefficients of 0.432 - 0.999. The correlation between each growth character was related to stand age interval, and shorter interval led to closer correlation. The results of cluster analysis showed that the positive selection rate was 85.71%, the wrong selection rate was 14.29%, and the omission rate was 0%, compared with the fast growing clones selected at the age of 30 years. At the age of 30 years, the overall genetic gain of DBH, height and volume of 6 fast growing clones were 21.86%,18.32% and 61.19 %, while those of actual gain were 29.86%, 24.93% and 92.92%, respectively. Based on comprehensive evaluation using Bregin's multiple traits,79172 (1.705) was the best, followed by 7911 (1.698),8213 (1.688), 8237 (1.672), 79173 (1.666) and 8219 (1.664). [Conclusion] The growth traits of C. lanceolata clones had rich genetic variation and were controlled by high genetic control, showing good potential for genetic improvement. The age of 15 years was the earliest suitable age for selection of fast growing clones of C. lanceolata to improve efficiency of genetic improvement. The 30-year-old clones of 79172 and 7911 were selected according to the selection rate of less than 5% for popularization in Yongzhou forest area, Hunan. [ABSTRACT FROM AUTHOR]

To understand the reliability of genetic determination and early selection of Pinus koraiensis, the genetic variation of growth traits of 34 full-sib families in different growth year were investigated and analyzed. The results showed significant differences in female and male parents and their interaction at different ages, and genetic variance components of growth traits between families accounted for over 50% of the total genetic variation. The phenotypic and genotypic coefficients of variation ranged from 8.61% to 27.29%, and from 6.71% to 19.96%, respectively. Meanwhile, broad-sense heritability and narrow-sense heritability ranged from 0.951–0.999, and from 0.566–0.681, respectively. Correlation analysis shown significant positive correlation coefficients between H, DBH, and V at different ages. Using the multiple-traits comprehensive evaluation method, seven families were selected in different ages. The estimated results of combining ability shown that female parent, male parent and parental combination were F 4, M 11 and F 9 × M 14, respectively. Therefore, the early genetic determination and selection of P. koraiensis could greatly shorten the breeding cycle, improve breeding efficiency, which could provide references for the early genetic determination of other tree species with long rotation age. [ABSTRACT FROM AUTHOR]

Genetic parameters were estimated for frosty pod rot resistance and yield components in cacao using a linear mixed model approach (restricted maximum likelihood and best linear unbiased prediction). Two progeny trials established in the Rosario Izapa Experimental Field of the INIFAP in Chiapas, Mexico, were evaluated for frosty pod rot incidence and yield components, including the number of pods per tree, bean dry weight per tree, number of beans per pod, bean dry weight per pod, seed index, and pod index, for 4 years. Genetic correlations, age-age correlations, and heritabilities were estimated. The narrow-sense heritability for frosty pod rot resistance was 0.46, and for the yield components, it ranged from 0.14 to 0.99. Backward selection, using UF-273 and Pa-169 as parents for new combinations, resulted in a reduction from −36.54 to −29.05% in frosty pod rot, respectively. The genetic correlations between bean dry weight per tree and frosty pod rot, number of pods per tree, number of beans per pod and pod index were −0.72, 0.89, 0.25, and 0.40, respectively (all significant at p < 0.01). Age-age correlations and heritabilities from data subsets indicated that the first 2 years of evaluation and evaluating for only two specific months (August to September) in the year should result almost in the same genetic estimates as using all 4 years data, for key traits, including frosty pod rot resistance, reducing the costs, and accelerating breeding decisions. [ABSTRACT FROM AUTHOR]

Bananas and plantains (Musa spp.) represent one of the most important products for food security and income generation. However, the production of these crops is threatened by the attack of diseases such as Panama disease or Fusarium wilt. In recent years there is a general consensus that the only form of effective and sustainable control, both economic and for this disease, is genetic improvement for resistance. Several biotechnology based strategies have been developed for the genetic improvement of the crop in obtaining individuals resistant or tolerant to fusariosis. The present work was carried out with the objective of providing a review of scientific literature related to the use of biotechnological tools in genetic improvement for resistance to fusarial wilt in bananas, with emphasis on in vitro, ex vitro and field selection for pathogen resistance. The results presented in this review demonstrate the potential of biotechnology in the field of genetic improvement in crops. Which allow to accelerate the genetic improvement programs of resistance to this disease. [ABSTRACT FROM AUTHOR]

The effects of early selection in a nursery on field performance were studied in an experiment comprising 2665 cutting-propagated clones of Picea abies (L.) Karst, deriving from 151 half-sib families. The clones were selected from 13,050 seedlings that were evaluated genetically using a randomized block design and measurements of height and growth rhythm in the nursery. The selected clones were assigned to six groups based on various criteria related to growth and phenology and to a comparison group of randomly selected clones. A group selected for height in the nursery gave an average gain in height after 6 years in the field of 9.1% compared with the randomly selected clones. Purely visual selection of plants with superior height, without considering the results of genetic evaluation, gave a gain of 3.8%. The gain in diameter after 12–14 years in the field was about two percentage units less but followed the same pattern. Other groups showed intermediate or less gain. Non-additive effects, expressed as clone-within-family effects, made substantial contributions to the total genetic gain. A test design that allows for genetic evaluation in the nursery appears to be a realistic option for achieving substantial gains in growth. [ABSTRACT FROM AUTHOR]

Wood properties are important traits that determine quality of structural wood. With the aim of performing efficient early selection for wood properties, we investigated genetic variation in 20 Larix kaempferi clones aged from 4 to 15 years for four quality traits: wood density, wall thickness to lumen area, microfibrillar angle (MFA) and modulus of elasticity (MOE). We observed that age-related trends in overall means varied for different traits: MFA decreased with the age, while the others generally increased with the age. Phenotypic variance always showed significant differences from the age of 8 years onward, with CVG ranging from 4% to 25%. Also, clonal repeatability increased steadily until 9 years old and then kept medium or higher intensity (0.4–0.8). After the age of 6, genetic correlations were generally higher than phenotypic correlations. Estimates of early selection efficiency suggested that the optimal selection age for wood density was at age 5–6 years, while it was 9–10 years for the other traits. In combination with previous results, we proposed a comprehensive early selection strategy for larch clonal breeding that involved selection based on nursery rooting ability, phenology, growth traits, and wood properties.

In this study, we aimed to evaluate half-sibling progenies of Myrocarpus frondosus based on morphological characteristics and to select seedlings with high growth vigor and quality. Seedlings were evaluated for shoot height and diameter, shoot height/diameter ratio, and number of leaves. The shoot height showed the highest estimations of linear correlation with the other characteristics. The linear correlation of shoot height between two consecutive evaluations was high from 60 days of cultivation, indicating that selection should be applied after this period. Selection of 101 seedlings within the best progenies resulted in a genetic gain of 15.13% for shoot height. The greatest indirect gain from selection was for the shoot height/diameter ratio, whereas the lowest indirect gain was for the stem diameter. Myrocarpus frondosus progenies can be selected for shoot height at 60 days of nursery cultivation, resulting in high direct gain for growth and indirect gain for stem height/diameter ratio. [ABSTRACT FROM AUTHOR]

Background and Objectives. Water stress is a major constraining factor of Eucalyptus plantations’ growth. Within a genetic improvement program, the selection of genotypes that improve drought resistance would help to improve productivity and to expand plantations. Leaf characteristics, among others, are important factors to consider when evaluating drought resistance evaluation, as well as the clone’s ability to modify leaf properties (e.g., stomatal density (d) and size, relative water content at the time of stomatal closure (RWCc), cuticular transpiration (Ec), specific leaf area (SLA)) according to growing conditions. Therefore, this study aimed at analyzing these properties in nursery plants of nine high-productivity Eucalyptus clones. Material and Methods: Five Eucalyptus globulus Labill. clones and four hybrids clones (Eucalyptus urophylla S.T. Blake × Eucalyptus grandis W. Hill ex Maiden, 12€; Eucalyptus urograndis × E. globulus, HE; Eucalyptus dunnii Maiden–E. grandis × E. globulus, HG; Eucalyptus saligna Sm. × Eucalyptus maidenii F. Muell., HI) were studied. Several parameters relating to the aforementioned leaf traits were evaluated for 2.5 years. Results: Significant differences in stomatal d and size, RWCc, Ec, and SLA among clones (p < 0.001) and according to the dates (p < 0.001) were obtained. Each clone varied seasonally the characteristics of its new developing leaves to acclimatize to the growth conditions. The pore opening surface potential (i.e., the stomatal d × size) did not affect transpiration rates with full open stomata, so the water transpired under these conditions might depend on other leaf factors. The clones HE, HG, and 12€ were the ones that differed the most from the drought resistant E. globulus control clone (C14). Those three clones showed lower leaf epidermis impermeability (HE, HG, 12€), higher SLA (12€, HG), and lower stomatal control under moderate water stress (HE, HG) not being, therefore, good candidates to be selected for drought resistance, at least for these measured traits. Conclusions: These parameters can be incorporated into genetic selection and breeding programs, especially Ec, SLA, RWCc, and stomatal control under moderate water stress. [ABSTRACT FROM AUTHOR]

Larix principis-rupprechtii Mayr is a dominant species in coniferous forests of North China. However, early selection of L. principis-rupprechtii for growth traits is poorly characterised. To explore the optimal selection age for this species, heights (HT) and diameters at breast (DBH) of 40 half-sib families were measured at ages 3, 12, 22, and 28 years in a progeny test population established in the town of Kangjiahui, Shanxi Province. Age trends in heritability, age–age genetic correlations, and early selection efficiency for height and DBH were analysed. The individual heritability of these growth traits varied over time, and maximized at different ages (0.55 at age 12 for HT and 0.48 at age 28 for DBH). The age–age genetic correlations were always positive, and the majority were high (0.790–0.953) between the juvenile and mature ages for HT and DBH. For the same pairs of measurements, HT demonstrated higher age–age genetic correlations than DBH, and both age–age genetic correlation data sets were described well by the linear relationship with the logarithm of the age ratio (r2 > 0.90). The regression slope for DBH was lower than that for HT. Based on the early selection efficiency estimates, the optimal selection age could be as early as age 6 for DBH and 8–9 years for HT. The results of this study provide information that can be used to assist early selection practices in L. principis-rupprechtii improvement programs in Shanxi Province. [ABSTRACT FROM AUTHOR]

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Salinity is one of the most severe environmental stresses, negatively affecting productivity of salt‐sensitive crop species. Given that germination is the most critical phase in the plant life cycle, the present study aimed to determine seed germination potential and associated traits under salt stress conditions as a simple approach to identify salt‐tolerant lentil genotypes.The genetic material consisted of six lentil genotypes whose adaptation to various agroclimatic conditions is not well elucidated. Salinity stress was applied by addition of NaCl at three different levels of stress, while non‐stressed plants were included as controls. Evaluation of tolerance was performed on the basis of germination percentage, seed water absorbance, root and shoot length, seedling water content, seedling vigour index and number of seedlings with an abnormal phenotype.Overall, our findings revealed that salinity stress substantially affects all traits associated with germination and early seedling growth, with the effect of salinity being dependent on the level of stress applied. It is noteworthy, however, that genotypes responded differently to the varying salinity levels. In this context, Samos proved the most salt‐tolerant genotype, indicating its possible use for cultivation under stress conditions.In conclusion, the determination of seed germination and early growth potential may be exploited as an efficient strategy to reveal genetic variation in lentil germplasm of unknown tolerance to salinity stress. This approach allows selection of desirable genotypes at early growth stages, thus enabling more efficient application of various breeding methods to achieve stress‐tolerant lentil genotypes. [ABSTRACT FROM AUTHOR]

Based on the 6-yea-old young forests of 40 cypress (Cupressus funebris') families from four provenances (Fengdu County, Youyang County and Zhong County of Chongqing City, and Qiandao Lake in Zhejiang Province) , differences in growth traits between families and provenances were studied to select excellent families, so as to provide necessary data support for the upgrading of cypress seed gardens and inferior thinning of seed gardens. The results showed that there were significant differences in tree height, diameter at one meter height, crown width and growth potential between families and provenances. The coefficients of variation among families were 10. 25% , 7. 19% , 5. 91% and 0. 98% , respectively, and the coefficients of variation in tree height and diameter at one meter height among provenances were 7. 25% and 12. 58% , respectively, indicating that the tree height and diameter at one meter height of the superior cypress tree families were rich in variation among families and provenances, and t here was potential for high-generation breeding. According to the selection rate of 15% , six excellent families for afforestation (Feng 8, Shi 4, Feng 1, Ye14, Shi 3 , andYe6) were screened. The average diameter at one meter height, tree height and crown width of the six excellent families were, respectively, 2.97 cm, 3.39 and 0.78 m, which were 18.82% , 12.70% and 15.42% higher than the family average, respectively, and 15.09% , 9.79% and 15.53% higher than the control group, respectively. [ABSTRACT FROM AUTHOR]

Este trabajo trata del estudio de estimativas de parámetros genéticos cuantitativos en un ensayo clonal para la selección precoz de clones superiores de eucalipto e posterior plantío comercial. De esta forma, el objetivo de este estudio fue estimar la variabilidad genética y determinar las correlaciones genéticas entre edades de selección en un ensayo clonal en el municipio de Botucatu, SP. El experimento fue instalado en un diseño de bloques completos al azar, siendo 23 clones (21 tratamientos y 2 testigos), repetidas 4 veces. Las parcelas fueron formadas por 25 plantas con distanciamiento de 3,0 x 2,0 m. Las características silviculturales como altura de planta, diámetro a la altura del pecho – DAP y volumen de madera fueron evaluadas a los 24, 36, 48 e 60 meses después del plantío. El análisis de los parámetros genéticos fue realizado con el programa estadístico GENES. Diferencias significativas fueron observadas para todos los caracteres en el análisis. Correlaciones altas y significativas fueron observadas entre los caracteres, indicando que la selección precoz puede proporcionar ganancias genéticas de hasta 34%. Los clones 18, 20 e 22 presentaron las mayores estimativas para volumen de madeira, demostrando potencial para ser aprovechado en los programas de mejoramiento genético y en plantíos comerciales, proporcionando buenos niveles de productividad para la región de Botucatu, SP.This work deals with the study of estimates of quantitative genetic parameters in a clonal assay for the early selection of superior clones of Eucalyptus and subsequent commercial planting. Thus, the aim of this study was to estimate the genetic variability and to determine the genetic correlations between the ages of clonal selection in a trial in the city of Botucatu, SP. The experiment was installed in a completely randomized design blocks (4) and 23 clones (21 treatment and 2 controls). The plots were formed by 25 plants with spacing of 3 x 2 m. Silvicultural traits as plant height, diameter at breast height – DBH and timber volume were evaluated at 24, 36, 48 and 60 months after planting. The analysis of genetic parameters was carried out with the statistical program GENES. Significant differences were observed for all traits in the analysis. High and significant correlations were observed between the traits, indicating that early selection can provide genetic gains up to 34%. Clones 18, 20 and 22 had the highest volume estimates for wood, showing potential to be exploited in breeding programs and commercial plantations, providing good levels of productivity for the region of Botucatu, SP.

The aim of this study was to evaluate the efficiency of selection of potato families in early generations for heat tolerance. Thirty families were evaluated in the seedling generation (SG), first clonal generation (FCG) in the field and greenhouse under high temperature conditions, and second clonal generation (SCG) under mild temperatures. The mean of the families was obtained in each generation. The 16 most productive families in FCG were selected, and the clones of these families were evaluated in experiments in the winter and rainy crop seasons. The results showed that family selection for tuber shape may be applied as of the SG. It was also observed that family selection in the FCG and SCG for yield and tuber specific gravity contributed to identification of clones tolerant to heat and responsive to environmental improvement.