Population-specific responses in eastern oysters exposed to low salinity in the northern Gulf of Mexico.

Eastern oysters, Crassostrea virginica, are facing rapid environmental changes in the northern Gulf of Mexico and can respond to these changes via plasticity or evolution. Plastic responses can immediately buffer against environmental changes, although this buffering may impact the organism's ability to evolve in subsequent generations. While plasticity and evolution are not mutually exclusive, the relative contribution and interaction between them remains unclear. In this study, we investigated the roles of plastic and evolved responses of C. virginica acclimated to low salinity using a common garden experiment with four populations exposed to two salinities. We used three transcriptomic analyses (edgeR, PERMANOVA and WGCNA) combined with physiology data to identify the effect of genotype (population), environment (salinity) and the genotype-environment interaction on both whole-organism and molecular phenotypes. We demonstrate that variation in gene expression is mainly driven by population, with relatively small changes in response to salinity. In contrast, the morphology and physiology data reveal that salinity has a larger influence on oyster performance than the population of origin. All analyses lacked signatures of the genotype×environment interaction and, in contrast to previous studies, we found no evidence for population-specific responses to low salinity. However, individuals from the highest salinity estuary displayed highly divergent gene expression from that of other populations, which could potentially drive population-specific responses to other stressors. Our findings suggest that C. virginica largely rely on plasticity in physiology to buffer the effects of low salinity, but that these changes in physiology do not rely on large persistent changes in gene expression.

Comparison of Marker Effects and Breeding Values at Two Levels at THI for Milk Yield and Quality Traits in Brazilian Holstein Cows.

Genomic tools can help in the selection of animals genetically resistant to heat stress, especially the genome-wide association studies (GWAS). The objective of this study was to compare the variance explained by SNPs and direct genomic breeding values (DGVs) at two levels of a temperature and humidity index (THI). Records of milk yield (MY), somatic cell score (SCS), and percentages of casein (CAS), saturated fatty acids (SFA), and unsaturated fatty acids (UFA) in milk from 1157 Holstein cows were used. Traditional breeding values (EBV) were determined in a previous study and used as pseudo-phenotypes. Two levels of THI (heat comfort zone and heat stress zone) were used as environments and were treated as "traits" in a bi-trait model. The GWAS was performed using the genomic best linear unbiased prediction (GBLUP) method. Considering the top 50 SNPs, a total of 36 SNPs were not common between environments, eight of which were located in gene regions related to the evaluated traits. Even for those SNPs that had differences in their explained variances between the two environments, the differences were very small. The animals showed virtually no rank order, with rank correlation values of 0.90, 0.88, 1.00, 0.88, and 0.97 for MY, CAS, SCS, SFA, and UFA, respectively. The small difference between the environments studied can be attributed to the small difference in the pseudo-phenotypes used between the environments, on-farm acclimation, the polygenic nature of the traits, and the THI values studied near the threshold between comfort and heat stress. It is recommended that future studies be conducted with a larger number of animals and at more extreme THI levels.

Genotype × region and genotype × production level interactions in Holstein cows.

The identification of the presence of genotype by environment interaction effects on important traits in Holstein cattle allows for the use of international genetic evaluations and a more efficient design of regional genetic evaluation programmes. The aim of this study was to determine the genotype × environment interaction effects in Chilean Holstein dairy cattle through the analysis of records corresponding to calvings between 1998 and 2015. Herds were classified in the central and southern regions of Chile based on herd location as well as by high and low levels of production environments based on the fat plus protein yield averages per herd within each region. The central region has a Mediterranean climate and a confined production system while the southern region has a humid temperate climate and a production system based on grazing with supplementation. Traits studied were milk yield (MY), fat yield (FY), protein yield (PY), fat content (FC) and protein content (PC) by lactation, age at first calving (AFC) and calving interval (CI). Several four-trait mixed animal models were applied to environmental category data as different traits, which included herd-year-calving season (herd-year-birth season for AFC) and lactation number as fixed effects, and animal additive genetic, sire-herd, permanent environment and residual effects as random effects. Genetic correlations (rg) for MY, FY, FC, PC and CI were found to decrease as differences between environmental categories increased. The rg between the most extreme environmental categories considered in this study for AFC (0.26) was the only one found statistically lower than 0.60. Genetic correlation values statistically lower than 0.80 (P < 0.05) were observed for AFC, CI, MY, FY and PY between some environmental categories. If separate genetic evaluations are adopted as practical criteria when the value of rg is lower than 0.60, the consequence of improving a multi-trait economic breeding objective in this population is likely to be small unless extreme environmental categories are considered. However, a moderate decrease in selection response and re-ranking of selection candidates is expected for AFC, CI and yield traits when selection is performed in different environmental conditions. Genotype × environment interaction effects involving production systems in a Mediterranean climate and confinement vs. Temperate Oceanic climate and grazing with supplementation, and between two fat plus protein yield level categories within each environment, were at most moderate for the studied traits.

A systemic approach to the quantification of the phenotypic plasticity of plant physiological traits: the multivariate plasticity index.

The phenotype of an individual emerges from the interaction of its genotype with the environment in which it is located. Phenotypic plasticity (PP) is the ability of a specific genotype to present multiple phenotypes in response to the environment. Past and current methods for quantification of PP present limitations, mainly in what constitutes a systemic analysis of multiple traits. This research proposes an integrative index for quantifying and evaluating PP. The multivariate plasticity index (MVPi) was calculated based on the Euclidian distance between scores of a canonical variate analysis. It was evaluated for leaf physiological traits in two cases using Brazilian Cerrado species and sugarcane varieties, grown under diverse environmental conditions. The MVPi was sensitive to plant behaviour from simple to complex genotype-environment interactions and was able to inform coarse and fine changes in PP. It was correlated to biomass allocation, showing agreement between plant organizational levels. The new method proved to be elucidative of plant metabolic changes, mainly by explaining PP as an integrated process and emergent property. We recommend the MVPi method as a tool for analysis of phenotypic plasticity in the context of a systemic evaluation of plant phenotypic traits.

Genetic effect of season on the preweaning growth of beef cattle: A first approach on Retinta calves / Efecto genético de la estación climática sobre el crecimiento predestete del ganado de carne: Un primer estudio en terneros de raza Retinta / Efeito genético de estações climáticas no crescimento pré-desmame de bovinos de corte: uma primeira abordagem para os bezerros Retinta

Abstract Background: Heat stress derived from global warming is causing major economic losses in the livestock industry. Objective: To develop a novel methodological approach for determining the influence of climatic factors on the estimation of genetic parameters for growth traits in Retinta cattle breed by using reaction-norm models. Methods: Live weight records (n=7,753) from 3,162 Retinta calves born from 1,249 dams and 85 sires and raised in the Andalusian region (Spain) were analyzed. The effect of heat stress was measured using the temperature-humidity index, calculated with climatological data obtained from four weather stations. A bivariate-random-regression reaction-norm model was used to estimate the (co)variance components of weight until weaning in two different climatic seasons corresponding to warm and cold months. Results: The heritability pattern of individuals reared under diverse environments during the first 90 days of age was different. However, differences were not significant at the end of the growing period. Weaned calves reared during the cold season showed greater growth from 70 to 160 days in comparison with those reared during the warm season. Conclusions: Overall, this assessment did not show significant effects of the genotype-environment interaction. However, highly significant evidence of genotype-climatic condition interaction was found during the calf´s first three months of age.

Resumen Antecedentes: El estrés térmico derivado del calentamiento global está causando pérdidas económicas en la industria ganadera. Objetivo: Desarrollar un enfoque metodológico para estimar la influencia de algunos factores climáticos sobre la estimación de parámetros genéticos en las variables de crecimiento de la raza bovina Retinta. Métodos: Se analizaron registros de peso vivo (n=7.753) de 3.162 terneros hijos de 1.249 vacas y 85 toros, criados en la región de Andalucía (España). El efecto del estrés térmico se midió mediante un índice de temperatura-humedad obtenido a partir de los datos de cuatro estaciones meteorológicas. Se usó un modelo bivariado de regresión aleatoria de "norma-reacción" para estimar la (co)varianza del peso hasta el destete en dos diferentes épocas climáticas correspondientes a los meses cálidos y fríos. Resultados: Se encontraron diferencias en el patrón de heredabilidad de individuos criados en diferentes ambientes durante los primeros 90 días de vida. Sin embargo, tales diferencias no fueron significativas al final del periodo de crecimiento. Los terneros destetados en la época fría mostraron un mayor crecimiento entre 70 y 160 días en comparación con los criados en la temporada cálida. Conclusiones: Se encontró una evidencia altamente significativa de la interacción genotipo-condición climática durante los primeros tres meses de crecimiento del ternero.

Resumo Antecedentes: O estresse térmico devido ao aumento da temperatura média está produzindo grandes perdas econômicas na indústria pecuária. Objetivo: Realizar uma nova abordagem metodológica para estimar a importância dos fatores climáticos em parâmetros genéticos em variáveis de crescimento da população da raça Retinta. Métodos: Foram analisados registros de peso vivo (n=7.753) de 3.162 Retinta bezerros, nascidos de 1.249 vacas e 85 touros criados na região da Andaluzia (Espanha). O efeito do estresse térmico foi medido utilizando o índice de temperatura-umidade obtido com dados climatológicos de quatro estações meteorológicas. Um modelo de regressão aleatória bivariado de norma-reação foi usado para estimar os componentes da (co)variância do peso à desmama em duas estações climáticas com correspondência aos meses quentes e fríos. Resultados: Diferenças foram encontradas no padrão de herdabilidade de indivíduos criados em diferentes ambientes nos primeiros 90 dias de idade. No entanto, essas diferenças não foram significativas no final do período de crescimento. Os bezerros desmamados globalmente na estação fria apresentaram um crescimento maior dos 70 aos 160 dias em comparação com os indivíduos criados na estação quente. Conclusões: Uma evidência altamente significativa da interação genótipo-ambiente foi encontrada durante os primeiros três meses de crescimento do bezerro.

Evaluación del rendimiento y calidad del fruto de parentales e híbridos de lulo de Castilla / Evaluation of the yield and fruit quality of parental and hybrids of lulo de Castilla

RESUMEN Solanum quitoense es una planta de gran relevancia para emprender proyectos productivos con fines de exportación, como frutal exótico o para la industria. Su importancia radica en la posibilidad de aportar al desarrollo de los productores de la región andina, debido a que el lulo es demandado en el mercado por su sabor, aroma, propiedades nutritivas y organolépticas. A pesar de su importancia, esta especie presenta deficiencias tecnológicas, entre las cuales, se destaca la falta de cultivares mejorados, que permitan garantizar mayores rendimientos y calidad de fruta y establecer su eficiencia agronómica, a través de diferentes ambientes. El objetivo de este trabajo fue evaluar el comportamiento del rendimiento y de las variables relacionadas con la fruta, en poblaciones de lulo de Castilla. Se utilizaron ocho parentales y 10 híbridos. En los municipios de La Florida y Buesaco, ubicados en el departamento de Nariño, se establecieron dos ensayos, bajo un diseño de Bloques Completos al Azar, con tres repeticiones. La interacción genotipo por ambiente fue significativa para el peso de fruto (PF), diámetro ecuatorial, sólidos solubles totales, contenido de jugo y rendimiento (RTO). En La Florida, B1, B2, B3, B4xB5 y B2XLaSelva fueron los de mejor comportamiento en cuanto a RTO, con promedios entre 6,64 a 9,35t.ha-1 y PF, con 143 a 167g, en su orden. En Buesaco, se destacaron B1 y B2xB8 con RTOs de 7,72 y 9,43t.ha-1 y PF, entre 92,03 y 112,97g, promedios que están por encima del promedio regional y son la base para mejorar estas características.

ABSTRACT Solanum quitoense is a plant of great relevance to undertake productive projects for export as an exotic fruit or for industry. Its importance lies in the possibility of contributing to the development of producers in the Andean region, because the lulo is demanded in the market for its flavor, aroma, nutritional and organoleptic properties. Despite its importance, this species has technological deficiencies, among which, the lack of improved cultivars that guarantee greater yields and fruit quality and establish its agronomic efficiency through different environments is highlighted. The objective of this work was to evaluate the performance of the yield and traits related to the fruit in populations of lulo de Castilla. Eight parents and 10 hybrids were used. In the municipalities of La Florida and Buesaco located in the department of Nariño, two trials were established under a Randomized Complete Blocks design with three repetitions. Genotype interaction by environment was significant for fruit weight (FP), equatorial diameter, total soluble solids, juice content and yield (RTO). In La Florida, B1, B2, B3, B4xB5 and B2XLaSelva were the best performers in terms of RTO with averages between 6.64 to 9.35t.ha-1 and PF with 143 to 167g, in order. In Buesaco, B1 and B2xB8 stood out with RTOs of 7.72 and 9.43t.ha-1, PF between 92.03 and 112.97g, averages that are above the regional average and are the basis for improving these characteristics.

Adaptability and phenotypic stability for productive and reproductive traits in Nelore cattle / Adaptabilidade e estabilidade fenotípica para características produtiva e reprodutiva em animais da raça Nelore

The present study aimed to estimate adaptability and stability parameters for Nellore bulls in 3 different regions. The traits analyzed included the weight of the animals raised in pasture at 420 days of age (W420) and at the age at first calving (AFC). The information used in this study was related to the phenotypic mean of the females which were the offspring of the top ten classified bulls based in one region. We used the methods proposed by Finlay & Wilkinson (1963) & Eberhart and Russell (1966) in order to evaluate the parameters of adaptability and stability of these animals. The averages estimated by the method of least squares were 243.91±34.90 kg and 1182.54±57.82 days, respectively, for the traits W420 and AFC. Adaptability and stability parameters for the W420 characteristic showed that it is feasible to identify bulls with predictable behavior in different environments, and that these animals may generate progenies which may achieve above-average performance. Behavior of the 10 bulls analyzed in the different regions studied for the traits W420 and AFC showed that the herds and the regions influenced the performance of their progenies. The methods used allowed us to identify bulls with general adaptability, high stability, and better performances, which may be the most suitable to be used in herds in which the genetic merit of the cows and the environment where the progenies will be raised are both unknown.(AU)

O objetivo deste trabalho foi estimar parâmetros de adaptabilidade e estabilidade para touros da raça Nelore em três regiões diferentes. As características analisadas foram o peso aos 420 dias de idade (P420) e a idade ao primeiro parto (IPP) de animais criados em regime de pasto. As informações utilizadas no estudo foram referentes a média fenotípica das fêmeas, filhas dos dez melhores touros classificados com base em uma região. Para avaliar os parâmetros de adaptabilidade e a estabilidade foram utilizadas as metodologias propostas por FINLAY & WILKINSON (1963) e EBERHART & RUSSELL (1966). As médias estimadas pelos métodos dos quadrados mínimos foram de 243,91±34,90kg e 1182,54±157,82 dias, respectivamente, para as características P420 e IPP. Os parâmetros de adaptabilidade e estabilidade para a característica P420 mostraram que é possível identificar os touros com comportamento previsível nos diferentes ambientes e que poderão gerar progênies com desempenho acima da média. O comportamento dos dez touros analisados nas diferentes regiões estudadas para as características P420 e IPP, evidenciaram que os rebanhos e as regiões influenciaram na performance de suas progênies. Por meio das metodologias aplicadas é possível identificar touros com adaptabilidade geral, alta estabilidade e com melhores desempenhos, os quais seriam os mais adequados a se utilizar em rebanhos em que não se conhece o mérito genético das vacas e nem o ambiente onde serão criadas as progênies.(AU)

Adaptability and phenotypic stability for productive and reproductive traits in Nelore cattle / Adaptabilidade e estabilidade fenotípica para características produtiva e reprodutiva em animais da raça Nelore

ABSTRACT: The present study aimed to estimate adaptability and stability parameters for Nellore bulls in 3 different regions. The traits analyzed included the weight of the animals raised in pasture at 420 days of age (W420) and at the age at first calving (AFC). The information used in this study was related to the phenotypic mean of the females which were the offspring of the top ten classified bulls based in one region. We used the methods proposed by Finlay & Wilkinson (1963) & Eberhart and Russell (1966) in order to evaluate the parameters of adaptability and stability of these animals. The averages estimated by the method of least squares were 243.91±34.90 kg and 1182.54±57.82 days, respectively, for the traits W420 and AFC. Adaptability and stability parameters for the W420 characteristic showed that it is feasible to identify bulls with predictable behavior in different environments, and that these animals may generate progenies which may achieve above-average performance. Behavior of the 10 bulls analyzed in the different regions studied for the traits W420 and AFC showed that the herds and the regions influenced the performance of their progenies. The methods used allowed us to identify bulls with general adaptability, high stability, and better performances, which may be the most suitable to be used in herds in which the genetic merit of the cows and the environment where the progenies will be raised are both unknown.

RESUMO: O objetivo deste trabalho foi estimar parâmetros de adaptabilidade e estabilidade para touros da raça Nelore em três regiões diferentes. As características analisadas foram o peso aos 420 dias de idade (P420) e a idade ao primeiro parto (IPP) de animais criados em regime de pasto. As informações utilizadas no estudo foram referentes a média fenotípica das fêmeas, filhas dos dez melhores touros classificados com base em uma região. Para avaliar os parâmetros de adaptabilidade e a estabilidade foram utilizadas as metodologias propostas por FINLAY & WILKINSON (1963) e EBERHART & RUSSELL (1966). As médias estimadas pelos métodos dos quadrados mínimos foram de 243,91±34,90kg e 1182,54±157,82 dias, respectivamente, para as características P420 e IPP. Os parâmetros de adaptabilidade e estabilidade para a característica P420 mostraram que é possível identificar os touros com comportamento previsível nos diferentes ambientes e que poderão gerar progênies com desempenho acima da média. O comportamento dos dez touros analisados nas diferentes regiões estudadas para as características P420 e IPP, evidenciaram que os rebanhos e as regiões influenciaram na performance de suas progênies. Por meio das metodologias aplicadas é possível identificar touros com adaptabilidade geral, alta estabilidade e com melhores desempenhos, os quais seriam os mais adequados a se utilizar em rebanhos em que não se conhece o mérito genético das vacas e nem o ambiente onde serão criadas as progênies.

Performance and stability of maize topcross hybrids from partly inbred lines / Desempenho e estabilidade de híbridos topcrosses de linhagens parcialmente endogâmicas de milho

Commercial hybrids are viable to generate base populations for obtaining new superior lines. Therefore, this study aimed to evaluate the performance and stability of maize topcross hybrids and select superior partly inbred lines. We evaluated 155 topcross hybrids of partly inbred lines crossed with an elite inbred line (tester) together with 14 commercial hybrids (2B688, AG7088, AS1575, DKB390, GNZ2005, GNZ8132, GNZ9501, GNZ9505, GNZ9548, GNZ9623, P30F35, P30F53, P30R50, and Penta) in Guarapuava-PR, Candói-PR, Guarda-Mor-MG, and Paracatu-MG (Brazil). The assessed variable was grain yield (GY), in kg ha-1, at 13% moisture, being the plant stand corrected by covariance method. A variance analysis was carried out, testing both stability and adaptability. There were significant differences for all sources of variation. By considering the GY means of the genotypes in each environment, Candói (10,985 kg ha-1) and Paracatu (10,917 kg ha-1) were in the first group, while Guarda-Mor (10,448 kg ha-1) was allocated in the intermediate group, and Guarapuava (10,159 kg ha-1) formed the group of lower GY means. None of the topcrosses stood out in any of the four environments, which may be related to the differences in climate and altitude between environments. Despite of this fact, lines 9, 13, 39, 40, 60, 93, 108, 179, 184, 189, 194, 211, 212, 213, 216, 217, 235, 243, 245, and 253 excelled as promising and should follow the process of inbreeding, in addition to the topcrosses 87, 144, 179, and 211, which also stood out for stability and adaptability in these environments.(AU)

Os híbridos comerciais são viáveis para gerar populações-base para obter novas linhagens superiores. Portanto, o objetivo deste trabalho foi avaliar o desempenho e estabilidade de híbridos topcrosses de milho e selecionar híbridos superiores e/ou linhagens parcialmente endogâmicas com potencial superior. Foram avaliadas 155 linhagens parcialmente endogâmicas em cruzamentos topcrosses com uma linhagem elite (testador) juntamente com 14 híbridos comerciais (2B688, AG7088, AS1575, DKB390, GNZ2005, GNZ8132, GNZ9501, GNZ9505, GNZ9548, GNZ9623, P30F35, P30F53, P30R50 e Penta) em Guarapuava-PR, Candói-PR, Guarda-Mor-MG e Paracatu-MG. Foi avaliado a produtividade de grãos (GY) em kg ha-1 com 13% de umidade em que o estande de plantas foi corrigido pelo método da covariância. Fez-se análise de variância dos dados e de estabilidade e adaptabilidade. Houve efeito significativo para todas as fontes de variação. Considerando a média de GY em kg ha-1 dos genótipos em cada ambiente, Candói (10,985 kg ha-1) e Paracatu (10,917 kg ha-1) foram alocados no primeiro grupo, enquanto Guarda-mor (10,448 kg ha-1) foi alocado no grupo intermediário e Guarapuava (10,159 kg ha-1) formou o pior grupo de médias. Não houve híbridos topcrosses que se destacaram nos quatro ambientes. Apesar deste fato, as linhagens 9, 13, 39, 40, 60, 93, 108, 179, 184, 189, 194, 211, 212, 213, 216, 217, 235, 243, 245 e 253 são promissoras e devem seguir no programa de melhoramento no processo de endogamia e os híbridos topcrosses 87, 144, 179 e 211 também se destacam por estar entre os melhores em mais de dois ambientes, sendo estáveis e adaptados e podem ser utilizados para cultivo nestes ambientes.(AU)

Performance and stability of maize topcross hybrids from partly inbred lines / Desempenho e estabilidade de híbridos topcrosses de linhagens parcialmente endogâmicas de milho

Commercial hybrids are viable to generate base populations for obtaining new superior lines. Therefore, this study aimed to evaluate the performance and stability of maize topcross hybrids and select superior partly inbred lines. We evaluated 155 topcross hybrids of partly inbred lines crossed with an elite inbred line (tester) together with 14 commercial hybrids (2B688, AG7088, AS1575, DKB390, GNZ2005, GNZ8132, GNZ9501, GNZ9505, GNZ9548, GNZ9623, P30F35, P30F53, P30R50, and Penta) in Guarapuava-PR, Candói-PR, Guarda-Mor-MG, and Paracatu-MG (Brazil). The assessed variable was grain yield (GY), in kg ha-1, at 13% moisture, being the plant stand corrected by covariance method. A variance analysis was carried out, testing both stability and adaptability. There were significant differences for all sources of variation. By considering the GY means of the genotypes in each environment, Candói (10,985 kg ha-1) and Paracatu (10,917 kg ha-1) were in the first group, while Guarda-Mor (10,448 kg ha-1) was allocated in the intermediate group, and Guarapuava (10,159 kg ha-1) formed the group of lower GY means. None of the topcrosses stood out in any of the four environments, which may be related to the differences in climate and altitude between environments. Despite of this fact, lines 9, 13, 39, 40, 60, 93, 108, 179, 184, 189, 194, 211, 212, 213, 216, 217, 235, 243, 245, and 253 excelled as promising and should follow the process of inbreeding, in addition to the topcrosses 87, 144, 179, and 211, which also stood out for stability and adaptability in these environments.

Os híbridos comerciais são viáveis para gerar populações-base para obter novas linhagens superiores. Portanto, o objetivo deste trabalho foi avaliar o desempenho e estabilidade de híbridos topcrosses de milho e selecionar híbridos superiores e/ou linhagens parcialmente endogâmicas com potencial superior. Foram avaliadas 155 linhagens parcialmente endogâmicas em cruzamentos topcrosses com uma linhagem elite (testador) juntamente com 14 híbridos comerciais (2B688, AG7088, AS1575, DKB390, GNZ2005, GNZ8132, GNZ9501, GNZ9505, GNZ9548, GNZ9623, P30F35, P30F53, P30R50 e Penta) em Guarapuava-PR, Candói-PR, Guarda-Mor-MG e Paracatu-MG. Foi avaliado a produtividade de grãos (GY) em kg ha-1 com 13% de umidade em que o estande de plantas foi corrigido pelo método da covariância. Fez-se análise de variância dos dados e de estabilidade e adaptabilidade. Houve efeito significativo para todas as fontes de variação. Considerando a média de GY em kg ha-1 dos genótipos em cada ambiente, Candói (10,985 kg ha-1) e Paracatu (10,917 kg ha-1) foram alocados no primeiro grupo, enquanto Guarda-mor (10,448 kg ha-1) foi alocado no grupo intermediário e Guarapuava (10,159 kg ha-1) formou o pior grupo de médias. Não houve híbridos topcrosses que se destacaram nos quatro ambientes. Apesar deste fato, as linhagens 9, 13, 39, 40, 60, 93, 108, 179, 184, 189, 194, 211, 212, 213, 216, 217, 235, 243, 245 e 253 são promissoras e devem seguir no programa de melhoramento no processo de endogamia e os híbridos topcrosses 87, 144, 179 e 211 também se destacam por estar entre os melhores em mais de dois ambientes, sendo estáveis e adaptados e podem ser utilizados para cultivo nestes ambientes.

Sensitivity of breeding values for carcass traits of meat-type quail to changes in dietary (methionine + cystine):lysine ratio using reaction norm models.

Our objective was to evaluate changes in breeding values for carcass traits of two meat-type quail (Coturnix coturnix) strains (LF1 and LF2) to changes in the dietary (methionine + cystine):lysine ([Met + Cys]:Lys) ratio due to genotype by environment (G × E) interaction via reaction norm. A total of 7000 records of carcass weight and yield were used for analyses. During the initial phase (from hatching to day 21), five diets with increasing (Met + Cys):Lys ratios (0.61, 0.66, 0.71, 0.76 and 0.81), containing 26.1% crude protein and 2900 kcal ME/kg, were evaluated. Analyses were performed using random regression models that included linear functions of sex (fixed effect) and breeding value (random effect) for carcass weight and yield, without and with heterogeneous residual variance adjustment. Both fixed and random effects were modelled using Legendre polynomials of second order. Genetic variance and heritability estimates were affected by both (Met + Cys):Lys ratio and strain. We observed that a G × E interaction was present, with changes in the breeding value ranking. Therefore, genetic evaluation for carcass traits should be performed under the same (Met + Cys):Lys ratio in which quails are raised.

Multiple-breed reaction norm animal model accounting for robustness and heteroskedastic in a Nelore-Angus crossed population.

Our objective was to genetically characterize post-weaning weight gain (PWG), over a 345-day period after weaning, of Brangus-Ibagé (Nelore×Angus) cattle. Records (n=4016) were from the foundation herd of the Embrapa South Livestock Center. A Bayesian approach was used to assess genotype by environment (G×E) interaction and to identify a suitable model for the estimation of genetic parameters and use in genetic evaluation. A robust and heteroscedastic reaction norm multiple-breed animal model was proposed. The model accounted for heterogeneity of residual variance associated with effects of breed, heterozygosity, sex and contemporary group; and was robust with respect to outliers. Additive genetic effects were modeled for the intercept and slope of a reaction norm to changes in the environmental gradient. Inference was based on Monte Carlo Markov Chain of 110 000 cycles, after 10 000 cycles of burn-in. Bayesian model choice criteria indicated the proposed model was superior to simpler sub-models that did not account for G×E interaction, multiple-breed structure, robustness and heteroscedasticity. We conclude that, for the Brangus-Ibagé population, these factors should be jointly accounted for in genetic evaluation of PWG. Heritability estimates increased proportionally with improvement in the environmental conditions gradient. Therefore, an increased proportion of differences in performance among animals were explained by genetic factors rather than environmental factors as rearing conditions improved. As a consequence response to selection may be increased in favorable environments.

Reação de genótipos de soja de ciclo semiprecoce e médio quanto à severidade de manchas foliares / Reaction of semiearly and medium cycle soybean genotypes to leaf spots severity

Este trabalho teve como objetivo avaliar 28 genótipos de soja, pertencentes ao ciclo semiprecoce/médio em quatro localidades. Estes materiais foram avaliados quanto à severidade de manchas foliares (mancha parda, mancha olho-de-rã, oídio e míldio) e produtividade de grãos. Utilizou-se o delineamento experimental de blocos casualizados, com três repetições. Verificou-se interações significativas entre genótipos x ambientes para as variáveis severidade de mancha parda, oídio, míldio, mancha olho-de-rã e produtividade. A linhagem UFUS 18, proveniente do cruzamento entre IAC 100 x Emgopa 302, mostrou-se produtiva e resistente às manchas foliares. Os genótipos UFUS 8 (IAS 5 x Emgopa 302), UFUS 22 (IAC 100 x Emgopa 302) e UFUS 23 (Cristalina x IAC 100) foram promissores, devendo ser indicados em Uberaba e Uberlândia, Uberaba e São Gotardo e Uberaba, respectivamente.

This study evaluated 28 semi-early and medium cycle soybean genotypes in four locations. These were evaluated for leaf spots (brown spot, frogeye leaf spot, powdery and downy mildews) severity and yield productivity. The statistical design was randomized blocks with three repetitions. There was a significant interaction between genotype x environment variables for the severity of brown spot, powdery mildew, downy mildew, frogeye leaf spot and yield productivity. Line 18, from the crossing IAC 100 x Emgopa 302, was more productive and presented resistance reaction to leaf spots. The genotypes 8 (IAS 5 x Emgopa 302), 22 (IAC 100 x Emgopa 302) and 23 (Cristalina x IAC 100) are promising and should be indicated by location.

Análises Biplot: conceitos, interpretações e aplicações / Biplot analysis: concepts, interpretations and uses

A seleção e recomendação de genótipos superiores são dificultadas devido à ocorrência da interação genótipo e ambiente. Nesse contexto, as análises biplot têm sido cada vez mais utilizadas na análise de dados agronômicos, com interações de natureza complexa. Entretanto, as particularidades existentes no gráfico biplot dificultam sua interpretação, podendo induzir o pesquisador a erros. Assim, este artigo de revisão discute a aplicabilidade e a interpretação gráfica dos modelos AMMI (Additive Main effects and Multiplicative Interaction) e GGE biplot (genotype main effects + genotype environment interaction) destas análises no gráfico biplot. Também, visa a desmistificar a necessidade de comparação entre ambas as metodologias. Discute-se quanto à escolha da metodologia mais adequada, levando em consideração a informação requerida e os objetivos do pesquisador.

The genotype environment interaction (GE) influences on the selection and recommendation of cultivars. Biplot analysis has been increasingly used in data analysis of complex traits in agriculture. However, the peculiarities of biplot graphic could induce the researcher to errors on interpretation. Thus, this review argues the applicability and graphic interpretation of models AMMI (Additive Main Effects and Multiplicative Interaction) and GGE biplot (genotype main effects + genotype environment interaction). Moreover, also aims to explain that it is not adequate to compare both statistical methods. It is discussed the best methodology considering the information required and the research objectives.

Adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais / Adaptability and phenotypic stability of sugarcane genotypes in the state of Minas Gerais

O objetivo deste trabalho foi avaliar a adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais. Foram avaliados 15 genótipos em nove ambientes. Os experimentos foram conduzidos em blocos completos casualizados, com três repetições. Para discriminar os genótipos, utilizou-se a variável TPH (toneladas de pol por hectare). Os valores corresponderam à média de dois cortes. Os resultados revelaram que a cultivar testemunha RB867515 apresentou maior adaptabilidade geral e estabilidade fenotípica, seguida pelo genótipo RB987935, que apresentou a maior média e elevada adaptabilidade geral e específica para ambientes favoráveis e desfavoráveis, podendo ser indicada para cultivo comercial.

The objective of this research was to evaluate the adaptability and phenotypic stability of genotypes of sugarcane in the state of Minas Gerais, Brazil. There had been evaluated 15 genotypes in nine environments. The experiments were conducted in a randomized block design with three replications. To discriminate the genotypes the variable TPH (tons of pol per hectare) was used. These values corresponded to the average of two cuts. The results showed that the check RB867515 presented greater general adaptability and phenotypic stability, followed by genotype RB987935, which had the highest average and high general and specific adaptability to favorable and unfavorable environments that may be suitable for commercial cultivation.

Análises Biplot: conceitos, interpretações e aplicações

The genotype environment interaction (GE) influences on the selection and recommendation of cultivars. Biplot analysis has been increasingly used in data analysis of complex traits in agriculture. However, the peculiarities of biplot graphic could induce the researcher to errors on interpretation. Thus, this review argues the applicability and graphic interpretation of models AMMI (Additive Main Effects and Multiplicative Interaction) and GGE biplot (genotype main effects + genotype environment interaction). Moreover, also aims to explain that it is not adequate to compare both statistical methods. It is discussed the best methodology considering the information required and the research objectives.

A seleção e recomendação de genótipos superiores são dificultadas devido à ocorrência da interação genótipo e ambiente. Nesse contexto, as análises biplot têm sido cada vez mais utilizadas na análise de dados agronômicos, com interações de natureza complexa. Entretanto, as particularidades existentes no gráfico biplot dificultam sua interpretação, podendo induzir o pesquisador a erros. Assim, este artigo de revisão discute a aplicabilidade e a interpretação gráfica dos modelos AMMI (Additive Main effects and Multiplicative Interaction) e GGE biplot (genotype main effects + genotype environment interaction) destas análises no gráfico biplot. Também, visa a desmistificar a necessidade de comparação entre ambas as metodologias. Discute-se quanto à escolha da metodologia mais adequada, levando em consideração a informação requerida e os objetivos do pesquisador.

Adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais

The objective of this research was to evaluate the adaptability and phenotypic stability of genotypes of sugarcane in the state of Minas Gerais, Brazil. There had been evaluated 15 genotypes in nine environments. The experiments were conducted in a randomized block design with three replications. To discriminate the genotypes the variable TPH (tons of pol per hectare) was used. These values corresponded to the average of two cuts. The results showed that the check RB867515 presented greater general adaptability and phenotypic stability, followed by genotype RB987935, which had the highest average and high general and specific adaptability to favorable and unfavorable environments that may be suitable for commercial cultivation.

O objetivo deste trabalho foi avaliar a adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais. Foram avaliados 15 genótipos em nove ambientes. Os experimentos foram conduzidos em blocos completos casualizados, com três repetições. Para discriminar os genótipos, utilizou-se a variável TPH (toneladas de pol por hectare). Os valores corresponderam à média de dois cortes. Os resultados revelaram que a cultivar testemunha RB867515 apresentou maior adaptabilidade geral e estabilidade fenotípica, seguida pelo genótipo RB987935, que apresentou a maior média e elevada adaptabilidade geral e específica para ambientes favoráveis e desfavoráveis, podendo ser indicada para cultivo comercial.

Forage yield in three pearl millet genotypes submitted to different chicken manure rates / Produtividade de forragem em três genótipos de milheto em diferentes doses de cama de aviário

The objectives of this work were to evaluate the forage yield of three pearl millet genotypes under different chicken manure rates and to verify the residual effect of this organic fertilizer on soil. An experiment was carried out in Papanduva, Santa Catarina, Brazil, during the 2008/09 and 2009/10 crop seasons. In the first crop season, three pearl millet genotypes were evaluated: a common genotype and two improved genotype (ADR 500 and LAB 733), which were cultivated under four chicken manure rates (0, 4, 8 and 12 t ha-1). In succession, the multicropping (black oat + common vetch) and pearl millet were cultivated to evaluated the residual effect of this organic fertilizer. The experimental design was a randomized blocks, with four replications. The pearl millet production was evaluated by cuts, while in multicropping between black oat + common vetch was evaluated the total dry mass. There was interaction between pearl millet genotypes and manure rates in relation to total shoot dry mass. The improved genotypes showed the higher performance due to increase manure rate. There was residual effect of this organic fertilizer on the multicroping of black oat + common vetch and pearl millet.

Os objetivos desse trabalho foram avaliar a produtividade de forragem em três genótipos de milheto, sob diferentes doses de cama de aviário e verificar o efeito residual desse fertilizante orgânico. Foi conduzido um experimento em Papanduva, SC, nas safras 2008/09 e 2009/10. Na primeira safra foram avaliados três genótipos de milheto, uma variedade comum e dois genótipos melhorados (ADR 500 e LAB 733), cultivados em quatro doses de cama de aviário (0, 4, 8 e 12 t ha-1). Em sucessão, foi cultivado um consórcio de aveiapreta + ervilhaca e, na sequência, milheto comum para verificar o efeito residual do fertilizante orgânico. O delineamento experimental foi o de blocos completos casualizados, com quatro repetições. Nas duas safras estivais, avaliou-se a produção de forragem pelo milheto por meio de cortes. No consórcio de aveia-preta + ervilhaca foi avaliada a produção de fi tomassa seca total. Houve interação entre genótipos de milheto e doses de cama de aviário para o total de fitomassa seca aérea, sendo que os genótipos melhorados demonstraram maior resposta produtiva frente ao aumento da dose de cama de aviário. Houve efeito residual significativo do fertilizante orgânico nos cultivos posteriores, constituídos pelo consórcio de aveia-preta + ervilhaca e milheto.

Adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais

The objective of this research was to evaluate the adaptability and phenotypic stability of genotypes of sugarcane in the state of Minas Gerais, Brazil. There had been evaluated 15 genotypes in nine environments. The experiments were conducted in a randomized block design with three replications. To discriminate the genotypes the variable TPH (tons of pol per hectare) was used. These values corresponded to the average of two cuts. The results showed that the check RB867515 presented greater general adaptability and phenotypic stability, followed by genotype RB987935, which had the highest average and high general and specific adaptability to favorable and unfavorable environments that may be suitable for commercial cultivation.

O objetivo deste trabalho foi avaliar a adaptabilidade e estabilidade fenotípica de genótipos de cana-de-açúcar no estado de Minas Gerais. Foram avaliados 15 genótipos em nove ambientes. Os experimentos foram conduzidos em blocos completos casualizados, com três repetições. Para discriminar os genótipos, utilizou-se a variável TPH (toneladas de pol por hectare). Os valores corresponderam à média de dois cortes. Os resultados revelaram que a cultivar testemunha RB867515 apresentou maior adaptabilidade geral e estabilidade fenotípica, seguida pelo genótipo RB987935, que apresentou a maior média e elevada adaptabilidade geral e específica para ambientes favoráveis e desfavoráveis, podendo ser indicada para cultivo comercial.

Análises Biplot: conceitos, interpretações e aplicações

The genotype environment interaction (GE) influences on the selection and recommendation of cultivars. Biplot analysis has been increasingly used in data analysis of complex traits in agriculture. However, the peculiarities of biplot graphic could induce the researcher to errors on interpretation. Thus, this review argues the applicability and graphic interpretation of models AMMI (Additive Main Effects and Multiplicative Interaction) and GGE biplot (genotype main effects + genotype environment interaction). Moreover, also aims to explain that it is not adequate to compare both statistical methods. It is discussed the best methodology considering the information required and the research objectives.

A seleção e recomendação de genótipos superiores são dificultadas devido à ocorrência da interação genótipo e ambiente. Nesse contexto, as análises biplot têm sido cada vez mais utilizadas na análise de dados agronômicos, com interações de natureza complexa. Entretanto, as particularidades existentes no gráfico biplot dificultam sua interpretação, podendo induzir o pesquisador a erros. Assim, este artigo de revisão discute a aplicabilidade e a interpretação gráfica dos modelos AMMI (Additive Main effects and Multiplicative Interaction) e GGE biplot (genotype main effects + genotype environment interaction) destas análises no gráfico biplot. Também, visa a desmistificar a necessidade de comparação entre ambas as metodologias. Discute-se quanto à escolha da metodologia mais adequada, levando em consideração a informação requerida e os objetivos do pesquisador.