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Sugar beet ( L. ssp. ) is one of the most important European crops for both food and sugar production. Crop improvement has been developed to enhance productivity, sugar content or other breeder's desirable traits. The introgression of traits from Crop Wild Relatives (CWR) has been done essentially for lessening biotic stresses constraints, namely using and species which exhibit disease resistance characteristics. Several studies have addressed crop-to-wild gene flow, yet, for breeding programs genetic variability associated with agronomically important traits remains unexplored regarding abiotic factors. To accomplish such association from phenotype-to-genotype, screening for wild relatives occurring in habitats where selective pressures are in play (i.e., populations in salt marshes for salinity tolerance; populations subjected to pathogen attacks and likely evolved resistance to pathogens) are the most appropriate streamline to identify causal genetic information. By selecting sugar beet CWR species based on genomic tools, rather than random variations, is a promising but still seldom explored route toward the development of improved crops. In this perspective, a viable streamline for sugar beet improvement is proposed through the use of different genomic tools by recurring to sugar beet CWRs and focusing on agronomic traits associated with abiotic stress tolerance. Overall, identification of genomic and epigenomic landscapes associated to adaptive ecotypes, along with the cytogenetic and habitat characterization of sugar beet CWR, will enable to identify potential hotspots for agrobiodiversity of sugar beet crop improvement toward abiotic stress tolerance.

Biotic and abiotic factors drive assortative mixing (preference for or sorting with individuals with similar characteristics) in animal populations on a landscape, with implications for dispersal, population structuring, and other ecological and evolutionary processes. However, patterns and generative mechanisms of assortative mixing are overlooked in amphibians outside of specific life history events such as reproduction. The aims of this project were to determine whether there is assortative mixing by size and life history category in eastern spadefoots (Scaphiopus holbrookii), whether these patterns are preserved across time and spatial scale, and quantify the nature and relative role of various habitat and soil features in explaining observed patterns in spatial organization of individuals. We conducted field surveys in southeastern Virginia, USA, in 2016 and 2017 during nonbreeding periods to create spatial networks of S. holbrookii. We quantified spatial assortativity by size and life history stage and evaluated the roles of multiple landscape features in explaining spatial organization of S. holbrookii. We found that S. holbrookii sorted spatially by size and sex outside of breeding periods, with juveniles and adults less likely to sort with each other. Within each life history stage, S. holbrookii sorted by size. These patterns were similar across time and spatial scale. Soil and habitat types had no effect on assortativity. Instead, the distance to nearest breeding pool, wetland, and meadow were related to life history stage assortativity, as well as size assortativity in males and subadults. Adult males and females displayed affinity for breeding pools and meadows and avoidance of other types of wetlands, while subadults and nonbreeding adults showed opposite patterns compared with breeding adults. Our results indicate that (1) previously established guidelines for the minimum size of buffer zones to protect wetland‐breeding amphibians may be inadequate, (2) nonbreeding wetlands may be important core habitat for subadults, and (3) the upland spatial organization of amphibians may be used to predict locations of undetected breeding pools.

Vernal pools provide critical breeding habitat for amphibians adapted to temporary waters, but they seldom receive the same level of protection as permanent wetlands. In response to continued degradation and loss of pools, managers often attempt to mitigate losses through pool creation or restoration. However, mitigation efforts often fail to provide suitable aquatic habitat for vernal pool amphibians. We review the literature on pool creation in northeastern and central North America, highlighting how and why constructed pools often fail to support amphibian-related objectives. We recommend that practitioners consider the complex ecology of pool ecosystems and the historical and current distribution of pools and other wetlands in their local context before designing pool mitigation projects. Using vernal pool creation as a mitigation option should be a last resort (i.e., when elimination of natural pools is unavoidable). Monitoring should be target-specific and conducted for at least 5 years. Topographic, geologic, and other local factors affecting pool hydrology and ecology vary regionally; pool creation remains an imperfect science that will only advance by documenting failures and successes. We recommend an adaptive management approach to vernal pool creation in which the effectiveness of techniques is evaluated and refined based on research.

Temporary forested pools are an important ecological resource throughout northern and eastern North America, yet they are often destroyed or degraded. Pool creation offers a potential mitigation solution, but long-term monitoring to assess the functioning of created pools is scarce. Furthermore, studies rarely integrate multiple, interacting levels of the pool ecosystem, including physical, chemical, and biological parameters. To address this knowledge gap, we compared the physical habitat, water chemistry, productivity, and community composition of macroinvertebrates and amphibians from 7-year old created pools ( n  = 7) to reference pools ( n  = 6). Created pools were smaller in size, received more sunlight, had greater amounts of Lemna , Typha , and Phragmites , and were less likely to dry. Created pools had higher pH and conductivity, but algal biomass did not differ. Macroinvertebrate richness was similar across pools, but composition starkly differed. Amphibian species richness and composition was similar between created and reference pools; however, created pools had fewer focal pool-breeding amphibians, including the spotted salamander and wood frog. By assessing the entire pool ecosystem, we found that the ability of created pools to mimic the physical conditions and ecological functions of natural temporary pools is suspect.

Wetland construction has been used as a tool to mitigate wetland loss, but constructed wetlands might not provide the same functions as natural wetlands. Hundreds of long-hydroperiod wetlands have been constructed within the Daniel Boone National Forest, Kentucky, in a ridge-top ecosystem where natural wetlands dry annually (i.e., have short hydroperiods). The constructed wetlands have been colonized by several amphibian species not historically associated with this ecosystem and that could have negative impacts on native amphibian species. We compared wood frog ( Lithobates sylvaticus ) reproductive success at constructed and natural wetlands and benefits of wood frog presence in constructed wetlands to eastern newts ( Notophthalmus viridescens ). Wood frog reproductive success was zero when eggs were laid in constructed wetlands: 7–70 % of eggs were consumed and no wood frog larvae were found. Eastern newts, present at all constructed wetlands, benefited from wood frog presence, i.e., newts in constructed wetlands with wood frog eggs had higher body condition than newts in natural wetlands. Wetland construction techniques should be altered so their hydrology mimics that of natural wetlands to support historically occurring species. Understanding the influence of species interactions, as habitat loss and modification increase, will continue to be critical for amphibian conservation.

To create proper living conditions for sea mammals kept in closed systems, one has to make sure that the characteristics of breeding pools, such as their shape, dimensions, the facing of the walls and bottom, as well as the quality and motion of water, resemble as closely as possible the natural environment of the animals. An appropriate system of water exchange plays a very important role here. A complete exchange of water is time-consuming, expensive and troublesome, so it can be performed only periodically and should be supported by a supplementary continuous exchange. This operation improves water quality and can create a proper velocity field in breeding pools. The breeding pools investigated in the present study are located in a sealarium in Hel (Poland), which belongs to the Institute of Oceanography of the Gdansk University. Tracer measurements, carried out in these reservoirs made it possible to evaluate the intensity of continuous water exchange. It was found that this intensity was insufficient (as evidenced by large dead zones in the pools and short detention time), and therefore alterations to the existing system were proposed (i.e. a tangential position of the inlet and a centrally situated outlet). On the basis of a simplified model of circulative water flow, it was shown that the altered hydraulic system can considerably improve the situation.

We integrated road maps, traffic volume data, and pool locations in a modeling study to estimate the potential effects of road mortality on populations of pool-breeding spotted salamanders (Ambystoma maculatum Shaw). Population projections based on spotted salamander life tables imply that an annual risk of road mortality for adults of >10% can lead to local population extirpation; mitigation efforts (tunnels, road closures, and other measures) should seek to reduce road mortality rates to below this threshold. For central and western Massachusetts, we estimated that salamanders would be exposed to at least this threshold level of risk at 22-73% of populations (assuming a 100 vs. 500 m migration distance, respectively). We conclude that road mortality can be a significant source of additive mortality for individual spotted salamanders in many parts of the species' range. Efforts to prevent such mortality by transportation planners are likely warranted strictly on a biological basis in areas with road densities >2.5 km per km^sup 2^ of landscape and traffic volumes >250 vehicles/lane/day within the migration range of a breeding population of spotted salamanders.[PUBLICATION ABSTRACT]

Modern high-yielding crop cultivars are known to have narrow genetic bases, making them vulnerable to biotic and abiotic stresses. However, little is known about the extent of deleterious genetic variants (or mutation burden) present in these cultivars. An attempt was made using RNA-Seq to screen genome-wide deleterious genetic variants in 141 oat and 142 wheat cultivars released through Canadian breeding programs over the past century. The screening identified 5726 and 3022 deleterious genetic variants across all 21 chromosomes of both the oat and wheat genomes, respectively. These deleterious variants were largely harbored in a few cultivars and were involved with diverse biological processes, cellular components, and molecular functions. More highly deleterious variants were predicted in oat, than in wheat, cultivars, and different gene expression profiles at the early seedling stage were observed between oat and wheat cultivars, illustrating different genetic impacts of the oat and wheat breeding programs. Estimating mutation burdens for each cultivar revealed large variations among both the oat and wheat cultivars. These mutation burdens were found to increase from early to recent oat and wheat cultivars and were associated with higher cultivar yields. Genetic analyses also revealed genetic shifts and expansions from early to recent oat and wheat cultivars. These findings provide the first empirical evidence of elevated mutation burdens in Canadian oat and wheat cultivars and are useful for advancing plant breeding programs to minimize genetic risk.

Abstract Genetic distances among different chickpea varieties and evaluation of their free amino acid profiles were determined on the basis of Sodium dodecyle sulphate polyacrylamide gels electrophoresis (SDS-PAGE). Total soluble proteins were resolved on 10% SDS Polyacrylamide gel. Low variability in tested varieties was observed. Dendogram based on electrophoretic data clustered the genotypes into 2 groups. The results showed that the average protein content of all the varieties was 26.01% within the range 22.8% for Thal-2006 to 34.06% Sheenghar-2000 of dry seed weight. On the basis of total protein content Bittal-98, Dasht and Sheen Ghar-2000, Karak-3 and CM-98, Paidar -91 and Fakhr-e-Thal, C-44, Balaksar and KK-1showed similar concentrations for protein contents among each other but showed variation from the rest of the varieties. Different proteins were separated on the basis of changes in their molecular weights by means of Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Dasht, CM-98, and Sheen Ghar showed 100% similarity. Balaksar and Fakhr-e- Thal, KK-2 and Chattan and KC-98, KK-1 and Lawaghar were 100% similar among each other but showed variation from the rest of the accessions. The overall dendrogram showed high and low level of variation among the accessions. The concentration of free amino acids varied among the 16 chickpea varieties. A significant difference of both essential and non-essential amino acids was found among the chickpea cultivars. The total concentration of essential amino acid was recorded 40.81 g/100 g protein while non-essential was recorded 59.18343 g/100 g protein in the given cultivars. The highest concentration of essential amino acids was found in C-44 followed by KK-2, KK-1 and Fakhr E Tal while the lowest concentration was recorded in Cm-98, Paidar-91 and Sheen Ghar-2000 respectively. Cultivars TAL-2006, Chattan and Karak-3 showed maximum concentration of both essential and endogenous amino acids. In conclusion; for broadening the genetic pools in breeding programs or to search for exotic characters, for instance new disease resistance alleles, accession with low similarity coefficients (Lawaghar and Battal-98) may be utilized. Furthermore the information acquired from this study could be used to device a proficient breeding approach intended at improving nutritional as well as broadening the genetic base of this essential food crop of Pakistan. Resumo As distâncias genéticas entre as diferentes variedades de grão-de-bico e a avaliação de seus perfis de aminoácidos livres foram determinadas com base na eletroforese em gel de poliacrilamida com dodecil sulfato de sódio (SDS-PAGE). As proteínas solúveis totais foram resolvidas em SDS-PAGE a 10%. Foi observada baixa variabilidade nas variedades testadas. O dendrograma fundamentado em dados eletroforéticos agrupou os genótipos em dois grupos. Os resultados mostraram que o teor médio de proteínas de todas as variedades foi de 26,01%, na faixa de 22,8% para Thal-2006 a 34,06% para Sheenghar-2000 do peso de sementes secas. Com base no conteúdo total de proteínas, Bittal-98, Dasht, Sheen Ghar-2000, Karak-3, CM-98, Paidar-91, Fakhr-e-Thal, C-44, Balaksar e KK-1 apresentaram concentrações semelhantes para o conteúdo de proteínas entre si, mas tiveram variação quanto ao restante das variedades. Diferentes proteínas foram separadas com base nas alterações de seus pesos moleculares por meio de eletroforese em gel de poliacrilamida com dodecil sulfato de sódio (SDS-PAGE). Dasht, CM-98 e Sheen Ghar mostraram 100% de similaridade. Balaksar, Fakhr-e-Thal, KK-2, Chattan e KC-98, KK-1 e Lawaghar foram 100% semelhantes entre si, mas apresentaram variação em relação ao restante dos acessos. O dendrograma geral mostrou alto e baixo nível de variação entre os acessos. A concentração de aminoácidos livres variou entre as 16 variedades de grão-de-bico. Foi encontrada uma diferença significativa entre os aminoácidos essenciais e não essenciais nas cultivares de grão-de-bico. A concentração total de aminoácidos essenciais foi registrada em 40,81 g / 100 g de proteína, enquanto a não essencial foi registrada em 59,18343 g / 100 g de proteína nas cultivares. A maior concentração de aminoácidos essenciais foi encontrada em C-44, seguida de KK-2, KK-1 e Fakhr-e-Thal, enquanto a menor concentração foi registrada em CM-98, Paidar-91 e Sheen Ghar-2000. As cultivares TAL-2006, Chattan e Karak-3 apresentaram concentração máxima de aminoácidos essenciais e endógenos. Em conclusão, para ampliar os pools genéticos em programas de melhoramento ou procurar caracteres exóticos, por exemplo, novos alelos de resistência a doenças, pode ser utilizada a adesão com baixos coeficientes de similaridade (Lawaghar e Battal-98). Além disso, as informações adquiridas neste estudo poderiam ser usadas para criar uma abordagem de criação eficiente, com o objetivo de melhorar a nutrição e ampliar a base genética dessa cultura alimentar essencial do Paquistão.

There is a pressing need to develop a sound conservation strategy for pool-breeding amphibians, which includes gaining a better understanding of the habitat and landscape-scale characteristics associated with populations. To investigate relationships between amphibian species richness and characteristics of breeding pools and surrounding landscapes, we surveyed 85 pools in eastern Massachusetts (USA) in 1996 and 1997. A total of 11 species was detected, with most pools having 2-5 species. Pools were typically small, 77.6% were <0.2 ha, but most pools (72%) had hydroperiods that persisted at least into August in most years. Based on linear regression analyses, species richness was positively associated with three within-pool variables (pool surface area, hydroperiod, and the amount of emergent vegetation), and a landscape-level variable (presence of another breeding pool within 1 km), while one within-pool variable (tree canopy cover) exhibited a significant negative association with species richness. These within-pool habitat variables and connectivity to other breeding pools are important characteristics to consider when attempting to identify breeding sites that could provide core habitat in conservation reserves designed for the conservation of pool-breeding amphibian species richness. Conservation reserves for pool-breeding amphibian populations should include pool complexes functioning as habitat for metapopulations. Core pool habitats within such reserves should be large (0.5-1.0 ha), with seasonal hydroperiods that persist into August or that dry in some years, and with sufficient emergent vegetation to provide diverse microhabitats and refugia.[PUBLICATION ABSTRACT]