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The use of computational resources to assess the physiological potential of seeds has attracted the attention of researchers and professionals in the seed sector. The aim of this study was to evaluate the vigor of cowpea seeds using the Vigor-S software (Automated Seed Vigor Analysis System), in comparison to the information provided by traditional vigor tests that are recommended for the species. Seven seed lots of the cultivar BRS Guariba were used. They underwent germination and seed vigor assessment by testing first germination count, accelerated aging, electrical conductivity, seedling emergence, speed of seedling emergence and use of Vigor-S, an automated image system for seedling assessment, in two evaluation periods. The data underwent analysis of variance, in a completely randomized design and their means were compared by the Scott-Knott test (p ≤ 0.05). An analysis was made of the correlation between the vigor tests traditionally used and the variables provided by Vigor-S. Using the Vigor-S software for automated image analysis of cowpea seedlings three days after sowing is an efficient alternative to detect differences in vigor between seed lots, similarly to traditional seed vigor evaluations. Resumo: O uso de recursos computacionais para a avaliação do potencial fisiológico de sementes tem atraído atenção de pesquisadores e profissionais do setor sementeiro. O objetivo deste estudo foi a avaliação do vigor de sementes de feijão-caupi com a utilização do software Vigor-S (Sistema de Análise Automatizada do Vigor de Sementes). Foram utilizados sete lotes de sementes do cultivar BRS Guariba que foram submetidos aos testes de primeira contagem de germinação, envelhecimento acelerado, condutividade elétrica, emergência de plântulas, velocidade de emergência de plântulas e sistema computadorizado de imagens de plântulas (Vigor-S), avaliados em duas épocas. Os dados foram submetidos a análise da variância, em delineamento inteiramente casualizado e suas médias comparadas pelo teste de Scott-Knott (p ≤ 0,05) e a análise de correlação entre os testes de vigor tradicionalmente utilizados e as variáveis fornecidas pelo Vigor-S. A análise computadorizada de imagens de plântulas de feijão-caupi com três dias após a semeadura por meio do software Vigor-S é uma alternativa eficiente para detectar diferenças de vigor entre os lotes de sementes, de forma similar às avaliações tradicionais do vigor de sementes.

This study examined whether the morphological attributes of Austrian pine (Pinus nigra ssp. nigra var. nigra Arnold) seedlings measured in the nursery could be used to forecast subsequent field performance over an extended time frame. Seedlings from three seed sources were produced in two types of containers and in bareroot seedbeds. These seedlings were measured for an array of morphological attributes (height, HT; root collar diameter, RCD; shoot height/diameter ratio, HD; shoot and root dry weight, SDW and RDW, respectively; shoot:root ratio, S:R; number of the first order lateral roots, FOLR; and Dickson quality index, DQI) and then planted at two sample plots with different soil depth. Seedling attributes were tested against field survival and growth in the first three years and growth in the twelfth year for their ability to forecast field performance. Correlations between morphological attributes and field performance were stronger for the plot with shallower soil, having potentially drier conditions. HT, HD, and S:R were the best attributes for forecasting seedling survival. HD was the most reliable attribute to forecast growth during the first three years after planting, defining the largest proportion of variation for growth (r2=0.36 to 0.86). Morphological attributes were better able to forecast field performance in the first three years at the shallow soil site, with FOLR the best single morphological variable. HT, DIA, and RDW were the best attributes to forecast growth during the first three years after planting on both sites. Morphological attributes were not able to forecast growth 12 years after planting.

Zeolitites, rocks with a content of zeolite group minerals greater than 50%, can serve as support for plant nutrients uptake, by enabling the slow release of macro- and micronutrients over time. Zeolitites equally improve soil cation exchange and water holding capacity. We analyzed the effect of zeolitite addition to the soil in forest restoration. We hypothesized that zeolitite ameliorated soil quality and consequently improved sward restoration and seedling establishment. Soil treatments were applied in 2014 and consist of: ploughed and ripped soil (non-amended) and ploughed, ripped and amended with zeolitite soil (amended). After application of the soil treatments, a herbaceous mixture was hand sown. Oak (Quercus robur L.), hawthorn (Crataegus monogyna Jacq.) and elm (Ulmus minor Mill.) seedlings were planted twice in the area, in autumn 2014 and autumn 2015. We monitored soil, sward and seedlings from 2015 to 2017. Seedling survival, which was generally above 50%, was never affected by zeolitite addition. The effect on seedling growth was significant only for hawthorn planted in 2015 that was approximately 5 cm taller in the amended soil. Herbaceous vegetation was also slightly affected by zeolitite addition. The zeolitite increased nitrogen (N) and phosphorus (P) Olsen in 2015, and exchangeable potassium (K) during the whole study period. Other parameters, such as year and growing season had significant effects on soil, sward and seedling dynamics. Time since restoration, plant-plant interactions, mechanical site preparation and meteorological conditions all together influenced the restoration dynamics more than zeolitite application.

8 páginas.- 5 figuras.- 2 tablas.- 60 referencias, Climate change and exotic pests and pathogens are causing alarming forest declines worldwide. However, we still lack a comprehensive understanding of how damage caused by exotic pests and pathogens might vary under the different scenarios of water availability imposed by a changing climate, particularly in water-limited forests as those that occupy Mediterranean areas. In this paper we aimed to experimentally analyse the interactive effects of the aggressive exotic pathogen Phytophthora cinnamomi and climate change-related reductions in soil moisture on seedling performance of the Mediterranean host Quercus suber. We conducted a full-factorial greenhouse experiment where the physiology and growth of Q. suber seedlings was measured in soils with different combinations of P. cinnamomi inoculum density (0, 30, 60 and 120 colony forming units per gram of dry soil) and soil moisture (15%, 40%, 50% and 100% soil water holding capacity) simulating different invasion and climate change scenarios. We found additive effects of P. cinnamomi and drought on Q. suber performance aboveground, although these effects were not always negative. In fact, seedlings showed a compensatory physiological response to P. cinnamomi infection by increasing their net photosynthetic rates. Our results also supported important interactive effects of pathogens and soil moisture on belowground performance. Thus, the inoculum density in the soil required to cause significant root damage in experimental seedlings decreased as soil moisture increased. From a climate change perspective, these results suggest that an average drier climate might imply sub-optimal conditions for P. cinnamomi infections allowing for a slower advance of the disease in invaded areas. However, this effect will be modulated by the also predicted more frequent extreme climatic events. A higher frequency of extreme rain events that saturate the soil might be particularly beneficial for P. cinnamomi, boosting its soil density beyond any possible response capacity of susceptible hosts. © 2019, This study was funded by the MICINN project INTERCAPA ( CGL2014-56739-R ). P.H. was supported by a FPI-MICINN grant, L.M. by an “Acción 6 UJA” fellowship (EI_RNM4_2017), O.G. by a Marie Sklodowska-Curie grant agreement ( No 661118-BioFUNC ), and I.M.P.R by a “Ramón & Cajal” contract ( RYC-2013-13937 ).

Early regeneration is a critical life stage that affects the future species composition of forests. Knowledge about regeneration success under different environmental conditions allows better understanding of forest dynamics. We studied the effects of seedbed conditions on the establishment and performance of seedlings of pedunculate oak, beech and red oak. In 50 plots of a tree-diversity oriented research platform in mature forests in northern Belgium (TREEWEB), we installed a field experiment with three treatments (potting soil, mineral soil, mineral soil + forest floor), in which we sowed seeds of each species. We monitored early establishment and survival, height, root and shoot biomass of the seedlings after two growing seasons. Mineral soil negatively affected seedling establishment and performance relative to the potting soil. The negative soil effects did not vary with measured abiotic soil properties. In general, the forest floor did not deteriorate or mitigate the soil effects, and only for root biomass did the forest floor partly compensate the negative soil effects. Forest floor effects did not vary with the measured forest floor properties. In the studied forests, creating bare soil was not enough to promote regeneration; improving soil properties might be important for the success of natural regeneration. Fil: De Groote, Stefanie R. E.. University of Ghent; Bélgica Fil: Vanhellemont, Margot. University of Ghent; Bélgica Fil: Baeten, Lander. University of Ghent; Bélgica Fil: Carón, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Salta; Argentina Fil: Martel, An. University of Ghent; Bélgica Fil: Bonte, Dries. University of Ghent; Bélgica Fil: Lens, Luc. University of Ghent; Bélgica Fil: Verheyen, Kris. University of Ghent; Bélgica

Aim of study: To assess the effectiveness for improving early seedling performance of the individual and combined application of (i) various doses of an innovative soil conditioner including polyacrylamide-free super-absorbent polymers, fertilizers, root precursors and humic acids; and (ii) innovative mulches based on renewable-biodegradable or recycled raw materials. The assessment was carried out in comparison with reference (commercial) soil conditioners and mulches. Area of study: Upper montane afforestation site located at 1,430 m altitude in the southern Pyrenees (NE Spain). Material and methods: We studied the effect of 15 treatments (various combinations of soil conditioners and mulches) on mountain ash (Fraxinus excelsior L.), testing survival, diameter and height growth and water and nutrient status during two growing seasons (2014-2015). We also assessed mulch durability during 2014-2016. Main results: The innovative soil conditioner improved diameter and height seedling growth (92% and 72% respectively) and water and nutrient status. The 40 g/seedling dosage was more cost-effective than the 20 and 80 g/seedling doses. The new formulation performed better in general than the commercial formulation. Mulches led to slight gains compared to control seedlings, and there were no major differences between the mulch models. The combined application of soil conditioners and mulches was not of particular interest. Research highlights: Soil conditioners consisting of synergic mixtures of water super-absorbent polymers, fertilizers, root growth precursors and humic acids can improve early seedling performance in coarse-textured, stony soils in montane conditions. Small mulches may be only of limited interest as long as weed competitiveness is poor. The research leading to these results has received funding from the European Union's Seventh Framework Programme managed by REA (Research Executive Agency), FP7/2007 2013, under grant agreement n° 606554 – Sustaffor project: Bridging effectiveness and sustainability in afforestation / reforestation in a climate change context: new technologies for improving soil features and plant performance. AA was supported by the Spanish Government through the ‘Juan de la C ierva’ fellowship program (IJC I-2016- 30049).

In this study, we determined the competition effects of herbaceous vegetation on survival, growth, and plant water relations of planted lenga (Nothofagus pumilio) seedlings under field and nursery conditions in western Patagonia, Argentina. In the field, thirty (1.5 × 1.5 m) plots were randomly set in a grazing-free exclosure built in a typical grazing-degraded lenga canopy gap mainly colonized by non-native herbs and grasses (empastado). Herbaceous aerial and root biomass was removed in half of the plots (non-competition treatment, NCT), while the others (competition treatment, CT), remained undisturbed. Four similarly-sized lenga seedlings were planted per plot. In the nursery, 120 lenga seedlings were planted in individual pots containing soil of the field study site, and set to a factorial experiment including two competition levels (CT and NCT) and two watering regimes: normal (simulating average rains during the growing season, 500 mm, NW), and high (equivalent to 1000 mm, HW). During three growing seasons, we determined seedling survival, growth, and plant and soil water status of both experiments. Higher survival and growth, and better plant water status values were obtained in NCT as compared to CT in both experiments. In the nursery, HW did not improve survival and growth as compared to NW. In restoration trials implying grazing-degraded areas, increases in lenga seedling survival and growth could be achieved by reducing nearby competition of grasses and herbs, while extra watering appears unnecessary. However, limitations in the experimental design (pseudo-replication), limits generalization of results to other forest ecosystems with similar structural and functional characteristics. Fil: Quinteros, Claudia Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina Fil: Bava, Jose Omar. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Lopez Bernal, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Gobbi, Miriam E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Defossé, Guillermo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina

In Andean Patagonia, Argentina, severe wildfires produce high mortality in Austrocedrus chilensis forests. Owing to its high timber quality, A. chilensis trees are generally salvage logged right after wildfires. Post-logged areas result in open, denuded stands with low herbaceous or shrub cover, which precludes natural A. chilensis regeneration. In severely burned A. chilensis stands, we determined how different site conditions (salvage logging, SL, and without logging, WL), and the combination of different methods of control of above-and belowground competition and micro-environmental factors (incident radiation, soil temperature and soil moisture) affected survival, growth and hydric status of planted A seedlings. Two growing seasons after plantation, seedling survival was lower than 10% at SL sites, whereas it was near 90% at WL sites. Four seasons after establishment, and regardless of competition treatments, no seedlings survived at SL sites, whereas over 75% survived at WL sites. Radiation attenuation by canopy of WL sites benefitted A. chilensis seedling survival, and no additional control of early successional herbaceous species should be necessary to attain high seedling survival 4 years after restoration. Selective logging, by leaving ∼50% of burned snags, and active restoration practices, may help reconcile economic needs of society and ecological requirements of A. chilensis for recovering former structure and functions. Fil: Urretavizcaya, María Florencia. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Ministerio de la Producción; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Defossé, Guillermo Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina

Understanding the mechanisms generating species distributions remains a challenge, especially in hyperdiverse tropical forests. We evaluated the role of rainfall variation, soil gradients and herbivory on seedling mortality, and how variation in seedling performance along these gradients contributes to habitat specialisation. In a 4-year experiment, replicated at the two extremes of the Amazon basin, we reciprocally transplanted 4638 tree seedlings of 41 habitat-specialist species from seven phylogenetic lineages among the three most important forest habitats of lowland Amazonia. Rainfall variation, flooding and soil gradients strongly influenced seedling mortality, whereas herbivory had negligible impact. Seedling mortality varied strongly among habitats, consistent with predictions for habitat specialists in most lineages. This suggests that seedling performance is a primary determinant of the habitat associations of adult trees across Amazonia. It further suggests that tree diversity, currently mostly harboured in terra firme forests, may be strongly impacted by the predicted climate changes in Amazonia.

This study aimed to evaluate the allelopathic effect of various concentrations of an aqueous extract of eucalyptus leaves on Urochloa decumbens and Panicum maximum seeds. The extract was prepared from Eucalyptus urograndis leaves that were milled and mixed with distilled water in a 1:9 milled leaves: water ratio to obtain an extract with a defined concentration of 100%. In addition, dilutions of 50%, 25% and 12.5% were prepared, and a 0% dilution was used as a control. The experiment followed a completely randomized design, with four replicates, each of 50 seeds of U. decumbens and 50 seeds of P. maximum, arranged on filter paper moistened with each concentration of extract in a Gerbox plastic box. The results demonstrated the allelopathic potential of E. urograndis aqueous extracts applied to the seeds of U. decumbens and P. maximum. The 50% and 100% concentrations of leaf extract most strongly inhibited the germination, vigor and seedling growth of U. decumbens and P. maximum. The germination speed index and the root length were the characteristics that were most affected by the potentially allelopathic substances contained in the eucalyptus extracts at all concentrations. Objetivou-se neste estudo avaliar o efeito alelopático de concentrações do extrato aquoso de folhas de eucalipto sobre sementes de Urochloa decumbens e Panicum maximum. O extrato foi preparado utilizando folhas de Eucalyptus urograndis moídas, as quais foram colocadas em água destilada na proporção de 1:9, obtendo-se a concentração de 100% e as diluições de 50%, 25%, 12,5% e 0% (testemunha). O ensaio foi montado em delineamento inteiramente casualizado, com quatro repetições de 50 sementes de U. decumbens e P. maximum, dispostas sobre papel-filtro umedecido com as concentrações do extrato, em caixas do tipo gerbox. Os resultados indicam a existência de potencial alelopático de E. urograndis sobre as espécies U. decumbens e P. maximum. Efeitos mais pronunciados na inibição da germinação e redução do vigor e do crescimento de plântulas de U. decumbens e P. maximum foram observados nas concentrações de 50% e 100% do extrato foliar de eucalipto. O índice de velocidade de germinação e o comprimento da radícula foram as características mais afetadas pelas substâncias potencialmente alelopáticas do extrato de eucalipto, em todas as concentrações.

High seed cost accompanied by poor germination and seedling performance renders cabbage nursery and field production enterprises unsustainable to many small-scale growers in tropical and sub-tropical countries. In most nurseries, adverse ecological conditions and pest damage are among the major factors responsible for poor seedling performance. The objective of this study was to test the potential use of eco-friendly net (EFN) covers as a low cost technology for sustainable cabbage seedling production. The study was a two-season experiment conducted using a randomized complete block design with five replications and two treatments. Treatments were: the standard open field transplant production (control) and transplant production under 0.4 mm mesh polyethylene net covering. EFN covering increased both temperature and relative humidity, enhanced seedling growth and reduced insect pest damage. Seed germination and seedling emergence were under the net covering earlier. Higher seed germination and seedling survival were recorded under the EFN treatment, indicating a potential for reducing the seed requirement per unit area of cabbage production. Seedlings grown under the nets had higher stomatal conductance and leaf chlorophyll content; furthermore, they grew taller, with more leaves within a shorter period of time compared to the control seedlings. The use of EFN in cabbage nurseries offers a sustainable technology for enhancing seedling performance by reducing pest infestation, thereby lowering production cost and improving the grower’s income.

Although maternal environmental effects are increasingly recognized as an important source of phenotypic variation with relevant impacts in evolutionary processes, their relevance in long-lived plants such as pine trees is largely unknown. Here, we used a powerful sample size and a strong quantitative genetic approach to analyse the sources of variation of early seedling performance and to identify seed mass (SM)-dependent and -independent maternal environmental effects in Maritime pine. We measured SM of 8924 individual seeds collected from 10 genotypes clonally replicated in two environments of contrasting quality (favourable and stressful), and we measured seedling growth rate and biomass allocation to roots and shoots. SM was extremely variable (up to 14-fold) and strongly determined by the maternal environment and the genotype of the mother tree. The favourable maternal environment led to larger cones, larger seeds and reduced SM variability. The maternal environment also determined the offspring phenotype, with seedlings coming from the favourable environment being 35% larger and with greater root/shoot ratio. Transgenerational plasticity appears, thus, to be a relevant source of phenotypic variation in the early performance of this pine species. Seed provisioning explained most of the effect of the maternal environment on seedling total biomass. Environmental maternal effects on seedling biomass allocation were, however, determined through SM-independent mechanisms, suggesting that other epigenetic regulation channels may be involved. © 2013 Macmillan Publishers Limited All rights reserved., This work was supported by the Spanish Plan Nacional de I+D+I [INIA-RTA2007-100, PSE310000, and AGL2010-18724] and co-financed by EU-FEDER. L.S. was supported by a DOC-INIA grant at the Centro de Investigación Forestal de Lourizán. We thank Xunta de Galicia for allowing us to work in the seed orchards. The two seed orchards were established by the Centro de Investigación Forestal de Lourizán, Xunta de Galicia., MICINN, INIA, EU-FEDER, Xunta de Galicia

1 Genotypic and plastic variation in plant size, and trade-offs among components of reproduction were studied using cloned individuals from 24 parental plants of the perennial hay-meadow species Lychnis-flos-cuculi, planted in four sites along a gradient of natural soil fertility. 2 Plant biomass, survival and fecundity differed significantly among clones and sites. Differences in survival and early components of fecundity among clones were strongly average rosette biomass attained during the first year. 3 There were significant clone-site interactions. However, a small number of clones which ranked high for plant biomass and fruit production at all sites, made a large contribution to local fruit production within a year across the entire gradient. 4 Patterns of biomass allocation and timing of first reproduction differed significantly among clones. A large part of this variation could be explained by clonal differences in average plant biomass attained during the first year. We conclude therefore that clonal variation in allocation patterns reflected differences in resource acquisition, rather than differences in partitioning strategies underlying life-history evolution. 5 Consequences of delaying first reproduction varied among sites. Precocity was favoured in the least productive site, whereas at intermediate soil fertility individuals that postponed reproduction gained a three-fold increase in fecundity at first reproduction, with no significant reduction in survival to this stage. Optimal timing of reproduction may thus vary at a small scale. 6 Genetically based trade-offs between only observed in the less productive sites. Costs of reproduction were also only apparent at such sites, supporting the idea that the expression of trade-offs and costs is most likely under low resource conditions. 7 In the more productive sites, within- and among-clone correlations between etative and generative reproduction, and among five components of fecundity were generally insignificant or positive. This available, differences in both microsite quality and resource a governed patterns of covariance. 8 Fruit predation by caterpillars of the noctuid Hadena bicruris was dependant on plant size. In the site with lowest individual fecundity, conferring a relative advantage to smaller sized individuals. [KEYWORDS: Allocation trade-offs; fecundity components; hadena bicruris; phenotypic plasticity; size hierarchies Reproductive characteristics; seedling performance; impatiens-capensis; viola-sororia; lanceolata l; selection; population;environment; yield; variability]