The efficiency of cultivar trial networks is an important subject in official cultivar testing. We investigated this efficiency for malting barley (Hordeum vulgare L.) in Uruguay, using data on 213 cultivars tested across an eight‐year period at six locations. The variance‐components approach was used to quantify the effects of years, locations, sowing dates and replicates on the precision of cultivar mean comparisons. The relationships among testing environments and genotypic adaptation patterns were explored via biplots. Factorial regression was used to model genotype × environment interaction (GEI) directly in relation to measured environmental variables. Variance components indicated that both the number of locations and sowing dates could be reduced. Biplot analysis identified some repeatable GEI patterns. Factorial regression showed that mean daily temperature during the emergence‐heading period and daily minimum temperature at heading explained 20% of GEI. Still, the majority of the GEI appeared to be highly nonrepeatable. A future network should focus on wide adaptation while enhancing the chances to exploit specific adaptation to the prevalent temperature conditions by sampling contrasting sowing dates at different locations.

Drought stress is one of the most important factors limiting soybean [Glycine max (L.) Merr.] productivity and reducing yield stability. Soybean breeders need phenotypic and genotypic tools to improve drought stress tolerance, but most of available strategies are expensive and unaffordable for small‐scale public breeding programs. In this study, elite germplasm of a locally adapted breeding population was used to estimate a yield stability index as an indicator of drought response. In order to associate yield stability of analyzed genotypes to drought response, water deficit scenarios related to the crop cycle group were defined. Four groups of genotypes were identified in relation to yield stability: two groups showed stables yield (without interaction with water deficit scenarios), and two groups showed unstable yield (with crossover interaction with water deficit scenarios). This phenotypic information was used to identify genomic regions and candidate genes associated with yield stability index. A new method for the definition of a quantitative trait loci (QTL) region was developed based on the probability of marker pairwise of belonging to four linkage disequilibrium (LD) categories. Seven QTL were found and their implication on drought tolerance was further supported by linkage to previously reported QTL for water use efficiency trait.

Las palomas torcazas (Zenaida auriculata) causan pérdidas que pueden representar hasta 50% de daño en algunos cultivos. El objetivo fue medir la aceptación de cebos contraceptivos para palomas torcazas en jaulas individuales (10 aves/tratamiento). Luego de la cuarentena y la aclimatación de las aves a la jaula, se les ofreció durante cuatro horas diarias por 21 días consecutivos tres presentaciones (tratamientos) del pellet con nicarbazina al 0,5%: (1) OvoControlS® diseñado para gorriones; (2) mezcla de OvoControlS® con maíz picado en proporción 78:22 y (3) OvoControlP® partido, diseñado para paloma doméstica (Columba livia). En la mañana se ofreció a cada ave el cebo del tratamiento, y por la tarde se ofreció dieta de mantenimiento en igual cantidad, y se registró lo ingerido. El consumo promedio/semana de OvoControlS® y de la mezcla OvoControlS® con maíz fue menor a 1,0g. El OvoControlP® partido fue aceptado por las aves. El consumo aumentó en las semanas 2 y 3 (p<0,05), superando 1,0g promedio/semana y fue mayor que las otras presentaciones (p<0,05). Se puede concluir que esta presentación de nicarbazina al 0,5% fue aceptada y consumida por palomas torcazas en condiciones de cautiverio, en cantidades que podrían causar un efecto en la reproducción de la especie

Drought limits crop productivity and reduces yield stability. Drought tolerance as a selection criterion in breeding programs requires the development of high-throughput, precise, and low-cost phenotyping strategies. We developed a mathematical model, based on biological approaches, for evaluating soybean plants’ response to drought under controlled growth conditions. The model describes the kinetics of water consumption of a plant pot substrate system (PPS) with low sampling requirements. The model generated two parameters, t0.5 (time necessary for the PPS to reach half of the maximum amount of evapotranspirable water) and Gw(t0.5) (stomatal conductance [Gw] at t0.5), which determined the water- consumption curve of each genotype. An analysis of the kinetics of water consumption in response to a progressive water deficit in a biparental and breeding population was performed as a preliminary test of the model. A correspondence analysis between the t0.5 and Gw(t0.5) parameters with the genetic structure of the populations shows a genetic association. The phenotyping methodology presented in this work and drought susceptibility in field conditions are discussed based on previous results. This work could be useful for improving the selection of soybean genotypes in relation to their performance under drought conditions.