Genotype by environment interaction for yearling weight in Nellore cattle applying reaction norms models

2018 ◽  
Vol 58 (11) ◽  
pp. 1996
Author(s):  
S. Ribeiro ◽  
J. P. Eler ◽  
V. B. Pedrosa ◽  
G. J. M. Rosa ◽  
J. B. S. Ferraz ◽  
...  
Keyword(s):  
Genetic Correlation ◽  
Environmental Gradient ◽  
Genotype By Environment Interaction ◽  
Reaction Norms ◽  
Breeding Value ◽  
Environment Interaction ◽  
Genotype By Environment ◽  
Genotype Environment Interaction ◽  
Nellore Cattle ◽  
Gradient Variation

In the present study, a possible existence of genotype × environment interaction was verified for yearling weight in Nellore cattle, utilising a reaction norms model. Therefore, possible changes in the breeding value were evaluated for 46 032 animals, from three distinct herds, according to the environmental gradient variation of the different contemporary groups. Under a Bayesian approach, analyses were carried out utilising INTERGEN software resulting in solutions of contemporary groups dispersed in the environmental gradient from –90 to +100 kg. The estimates of heritability coefficients ranged from 0.19 to 0.63 through the environmental gradient and the genetic correlation between intercept and slope of the reaction norms was 0.76. The genetic correlation considering all animals of the herds in the environmental gradient ranged from 0.83 to 1.0, and the correlation between breeding values of bulls in different environments ranged from 0.79 to 1.0. The results showed no effect of genotype × environment interaction on yearling weight in the herds of this study. However, it is important to verify a possible influence of the genotype × environment in the genetic evaluation of beef cattle, as different environments might cause interference in gene expression and consequently difference in phenotypic response.

scholarly journals Genetic evaluation of Devon Cattle using a reaction norms model

2010 ◽  
Vol 39 (1) ◽  
pp. 128-133 ◽  
Author(s):  
Marcela Bicca Bragança Corrêa ◽  
Nelson José Laurino Dionello ◽  
Fernando Flores Cardoso
Keyword(s):  
Environmental Gradient ◽  
Selection Process ◽  
Genotype By Environment Interaction ◽  
Reaction Norms ◽  
Environment Interaction ◽  
Improvement Program ◽  
Spearman Rank ◽  
Genotype By Environment ◽  
Conventional Animal ◽  
Selection Decision

The objective of this study was to evaluate differences in sire genetic values obtained by a conventional animal model (AM) and by a reaction norms hierarchical model (RNHM) that considers the genotype by environment interaction. A total of 25,500 records was used collected by PROMEBO - beef cattle improvement program of the National Breeders Association "Herd Book Collares" on Devon cattle born from 1980 though 2005. Post weaning gain 345 adjusted (PWG345) was the evaluated trait and the INTERGEN program was employed for data analysis. Reaction norms of the 25 sires with larger offspring showed ranking exchanges and scale effect in the environmental gradient. Spearman rank correlations between genetic values obtained by AM and RNHM at low, medium and high environmental levels were used to assess selection decision based on the different models. These correlations ranged from 0.12 and 0.99, therefore showing substantial changes in ranking, particularly between those genetic values obtained by the RNHM at low level compared to the same RNHM at medium and high levels and to AM, when considering the top 5% bulls. The results indicated that the selection process should consider the genotype by environmental interaction to maximize genetic gain and production of this population in each specific environment.

scholarly journals Assessment of Genotype by Environment Interaction Via Reaction Norms for Milk Yield in Holstein Cattle of Southern Brazil

2020 ◽  
Vol 20 (3) ◽  
pp. 1101-1112
Author(s):  
Henrique Alberto Mulim ◽  
Luis Fernando Batista Pinto ◽  
Aline Zampar ◽  
Gerson Barreto Mourão ◽  
Altair Antônio Valloto ◽  
...  
Keyword(s):  
Milk Production ◽  
Milk Yield ◽  
Genetic Correlations ◽  
Genotype By Environment Interaction ◽  
Reaction Norms ◽  
Random Regression ◽  
Breeding Value ◽  
Environment Interaction ◽  
Southern Brazil ◽  
Genotype By Environment

AbstractThe experiments reported in this research paper were aimed at assessing the genetic responses of a Holstein cow population, as a response to the variations in environmental temperature, through the analysis of the effects resulting from the genotype by environment interaction (GEI), based on reaction norms. Therefore, milk production data was collected from the database of the Paraná Holstein Breeders Association in Brazil for 67,360 primiparous cows born between 1990 and 2015, with the purpose of evaluating the temperature effect, considered as an environmental variable, distinguished under six gradients (17 ºC to 19.5 ºC) over the region. A random regression model was adopted, utilizing the fourth order under the Legendre polynomials, applying the mixed models of analysis by the REML method, and using the WOMBAT software. Additionally, the breeding value of the 15 most representative bulls was assessed, in response to the changes in the temperature gradient. The total milk production on average was estimated at 8,412.83 ± 2,012.08 kg. The heritabilities estimates were found in the low to moderate range, from 0.18 to 0.23, displaying a decline with a rise in the temperature, highlighting the influence it exerted on the heritabilities. Variations in the genetic expression of some bulls were noted to show differences of up to 289 kg of milk in response to the increase in the temperature from 17 ºC to 19.5 ºC. However, all the genetic correlations between the gradients for milk yield were above 0.80, in the range of 0.873 to 0.998, revealing no remarkable interaction between the genotype and environment. This result indicates that the application of the temperature variable in the models of genetic analysis in southern Brazil is not required.

Evaluation of sugarcane genotypes with respect to sucrose yield across three crop cycles using GGE biplot analysis

2021 ◽  
pp. 1-13
Author(s):  
Aliya Momotaz ◽  
Per H. McCord ◽  
R. Wayne Davidson ◽  
Duli Zhao ◽  
Miguel Baltazar ◽  
...  
Keyword(s):  
Block Design ◽  
Genotype By Environment Interaction ◽  
Environment Interaction ◽  
Gge Biplot ◽  
Genotype By Environment ◽  
Biplot Analysis ◽  
Genotype Environment Interaction ◽  
Area 5 ◽  
Randomized Complete Block Design ◽  
Main Effects

Summary The experiment was carried out in three crop cycles as plant cane, first ratoon, and second ratoon at five locations on Florida muck soils (histosols) to evaluate the genotypes, test locations, and identify the superior and stable sugarcane genotypes. There were 13 sugarcane genotypes along with three commercial cultivars as checks included in this study. Five locations were considered as environments to analyze genotype-by-environment interaction (GEI) in 13 genotypes in three crop cycles. The sugarcane genotypes were planted in a randomized complete block design with six replications at each location. Performance was measured by the traits of sucrose yield tons per hectare (SY) and commercial recoverable sugar (CRS) in kilograms of sugar per ton of cane. The data were subjected to genotype main effects and genotype × environment interaction (GGE) analyses. The results showed significant effects for genotype (G), locations (E), and G × E (genotype × environment interaction) with respect to both traits. The GGE biplot analysis showed that the sugarcane genotype CP 12-1417 was high yielding and stable in terms of sucrose yield. The most discriminating and non-representative locations were Knight Farm (KN) for both SY and CRS. For sucrose yield only, the most discriminating and non-representative locations were Knight Farm (KN), Duda and Sons, Inc. USSC, Area 5 (A5), and Okeelanta (OK).

scholarly journals Genetic Parameters and Genotype by Environment Interaction in Radiata Pine for Growth and Wood Quality Traits in Australia

2010 ◽  
Vol 59 (1-6) ◽  
pp. 113-124 ◽  
Author(s):  
Brian. S. Baltunis ◽  
W. J. Gapare ◽  
H. X. Wu
Keyword(s):  
Genetic Correlation ◽  
Genetic Parameters ◽  
Radiata Pine ◽  
Genotype By Environment Interaction ◽  
Environment Interaction ◽  
Tree Diameter ◽  
Genotype By Environment ◽  
Branch Angle ◽  
Stem Straightness ◽  
Branch Size

Abstract The phenotypic response of genotypes across different environments can be quantified by estimating the genotype by environment interaction (GxE). In a practical sense, GxE means that the relative performance of genotypes does not remain constant under all test conditions. Genetic parameters and genotype by environment interactions for wood density, growth, branching characteristics and stem straightness were investigated in eight radiata pine progeny trials derived from a second generation breeding population in Australia. Five trials were on the mainland, while three trials were in Tasmania. Generally, ĥ2 for density > branch angle > stem straightness > tree diameter > branch size; and significant ĥ2 was observed for all traits and at all trials with only two exceptions. Genetic correlations were estimated among the five traits, and a large negative genetic correlation observed between wood density and tree diameter indicated that a selection strategy should be developed in dealing with this adverse genetic correlation in advanced generations of breeding for radiata pine. Interactions for density, branch angle, and stem straightness were small within the two regions. Overall, branch angle had the least GxE, followed by density and stem straightness. Growth traits (tree diameter and branch size) tended to be the most interactive with substantial GxE present. Genotype by regional interactions (Mainland versus Tasmania) revealed that density and branch angle had the least interactions (ȓB = 0.98 and ȓB = 0.95, respectively). Branch size and tree diameter had the highest interactions among the two regions (ȓB = 0.55 and ȓB = 0.63, respectively). Within Tasmania, only branch size and tree diameter had a sizable interaction within the three sites. In contrast, there was little interaction for tree diameter among the Mainland trials. Branch size in the Mainland trials had a similar size of interaction as in Tasmania. Further research is recommended in identifying the cause of GxE for tree diameter and branch size in radiata pine across the entire radiata pine estate in Australia.

Estimation of genetic correlation between milk production and fat yield in different climates of Iran

2007 ◽  
Vol 2007 ◽  
pp. 70-70
Author(s):  
Sima Savar Sofla
Keyword(s):  
Genetic Correlation ◽  
Milk Production ◽  
Genetic Parameters ◽  
Genetic Difference ◽  
Genotype By Environment Interaction ◽  
Environment Interaction ◽  
Genotype By Environment ◽  
Heterogeneous Variances ◽  
Fat Yield ◽  
Different Climates

Performance of one genotype in similar climates is approximately the same but if this genotype is introduced into a different climate, its performance will be affected, based on Nizamani and Berger (1996). The function that relates phenotype to environment is unique for each genotype. Hence, the response to changes in environment may vary from one genotype to the other, based on Mulder et al. (2004). Different selection responses between environments are generally attributed to two types of genotype by environment interaction. The first type occurs when the genetic correlation between performances in two environments is substantially less than 1.0, indicating a genetic difference basis for the trait in the two environments. The second type of genotype by environment interaction results from heterogeneous variances, based on Ojango and Pollott (2002). The goal of this study was to estimate genetic (co)variances, environmental variances, and genetic parameters of milk production and fat yield among different environments in Iran to determine variables that are useful indicators of genotype by environment interaction.

scholarly journals Reaction norms in weights at 365 days old in nellore bulls in northern Brazil

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4613 ◽  
Author(s):  
Jorge Luís Ferreira ◽  
Alliny Souza de Assis ◽  
Fernando Brito Lopes ◽  
Thomas Wayne Murphy ◽  
Marcelo Corrêa da Silva ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Reaction Norm ◽  
Genotype By Environment Interaction ◽  
Random Regression ◽  
Residual Effects ◽  
Breeding Value ◽  
Environment Interaction ◽  
Nellore Cattle ◽  
Regression Techniques ◽  
Northern Brazil

<p>Genotype by environment interaction (GxE) studies are of particular interest in Brazil because of the regional diversity of environmental effects and the wide variety of management systems. The present study evaluates GxE effects on 365 d weight (365W) of Nellore cattle raised on pasture in northern Brazil. The analysis utilized random regression techniques to model the reaction norm. Fixed effects consisted of sex, contemporary group, and the covariate of age of cow at calving. The environmental gradient, defined by the concatenation of a bull and the state in which the calf was born, was modeled by second order Legendre polynomials. Direct additive genetic and residual effects were fit as random. Results showed differences in the magnitude of expression of genotype in proportion to decreasing favorability of the environment. As the environment became more unfavorable, the correlation of breeding value to different environments decreased. The correlations between the intercept and the level slope for 365W feature were of moderate magnitude, predominantly indicating the reclassification of sires in different environments. Reaction standard model was coherent from a technical and biological view point and enabled the perception of GxE in the genetic evaluation of Nellore cattle in the states of Maranhão, Pará and Tocantins.</p><p> </p>

The ecology and genetics of fitness in Chlamydomonas . I. Genotype-by-environment interaction among pure strains

1990 ◽  
Vol 240 (1298) ◽  
pp. 295-321 ◽  
Keyword(s):  
Environmental Factors ◽  
Genetic Correlation ◽  
Nonlinear Effects ◽  
Reaction Norms ◽  
Relative Fitness ◽  
Environment Interaction ◽  
Empirical Results ◽  
Genotype By Environment ◽  
The Difference ◽  
Interaction Variance

Strains of Chlamydomonas were cultured in different macroenvironments created by manipulating levels of nitrate, phosphate and bicarbonate in liquid growth media. Cell density, measured by optical transmittance, increased in a density-regulated manner, permitting the logistic par­ameters r and K to be estimated for each genotype–environment combination. The main empirical results of a factorial experiment were as follows. (i) A large proportion of the overall genotypic variance in fitness measures was attributable to genotype-by-environment (G × E) interaction: 65 % for r and 50 % for K . Variance components for r and K were uncorrelated, but components of the interaction variance may have been correlated with corresponding components of the environmental variance, such that the relative fitness of genotypes was most strongly affected by environmental factors that have the greatest effect on average fitness. Higher-order interactions were as large as lower-order interactions, so that relative fitness was sensitive to particular combinations of environmental factors as well as to their main effects. The covariance of r with K also showed strong G × E interaction, being negative in some macroenvironments and zero in others. (ii) An ‘environmental’ decomposition of the G × E interaction vari­ance separates ‘inconsistency’, due to lack of complete correlation between genotypes over macroenvironments, from ‘responsiveness’, due to differences between environmental variances among genotypes. Inconsistency was much the larger component for both r and K , showing that the greater part of the interaction variance was created by changes in the ranking of genotypes with respect to fitness between macroenvironments. When reaction norms were defined as the linear regressions of genotypic value on mean environmental value, substantial variance among reaction norms was detected : nonlinear effects were also large. (ii) A ‘genetic’ decomposition of the G × E interaction variance separates a component due to lack of complete genetic correlation from one due to differences in genetic variance. Incomplete genetic correlation was much the larger effect, the mean correlation between genotypes in two macroenvironments being only about +0.23 for r and +0.45 for K . A very striking observation was that the genetic correlation decreased as the difference between environments increased. It declined from +0.31 (for r ; + 0.58 for K ) when one factor differed between macroenvironments to +0.18 ( + 0.40) when two factors differed, and to +0.13 ( + 0.24) when all three factors differed. Furthermore, the genetic correlation varied inversely with the difference between environmental values, approaching zero when this difference was maximal. A measure of environmental consistency was obtained by plotting the score of a genotype in a given macroenvironment on its mean score over all macroenvironments, to identify environments in which generally inferior genotypes performed relatively well and vice versa. This analysis revealed some differences between macroenvironments, but nonlinear effects were again large. (iv) The two major empirical results of this investigation were ( a ) that much of the variance in fitness among genotypes is due to G × E inter­action caused by incomplete genetic correlation, and ( b ) that genetic correlation is smaller between environments that are less similar. Both the relevance and the limitations of these findings with respect to the interpretation of diversity are discussed.

GENOTYPE-ENVIRONMENT INTERACTION VARIANCES IN YIELD TRIALS OF FALL RYE

1970 ◽  
Vol 50 (1) ◽  
pp. 77-80 ◽  
Author(s):  
P. J. KALTSIKES
Keyword(s):  
Genotype By Environment Interaction ◽  
Western Canada ◽  
Environment Interaction ◽  
First Order ◽  
Genotype By Environment ◽  
Genotype Environment Interaction ◽  
Yield Difference ◽  
The Mean ◽  
Yield Trials ◽  
Interaction Variance

Estimates of genotype by environment interaction variances were obtained from the western Canada Co-operative fall rye tests grown in 1963–1967. All first-order interactions and the second-order interactions were significantly greater than zero at the 0.05 level of probability. Although the estimate of cultivar by year interaction variance was relatively small, it accounted for 40% of the variance of a cultivar mean when only three years of testing were considered. However, testing in 20 locations for three years with four replicates could detect yield differences of approximately 10% of the mean of the highest yielding cultivar. If further reduction of the yield difference detectable is desired, more locations should be included in the test.

Sign in / Sign up

Export Citation Format

Share Document