Genotypic and environmental effects on curd weight of autumn-maturing cauliflowers

SUMMARYTwelve genotypes of cauliflower were grown in two seasons from six seedling propagation treatments in three sequential sowings. There was a high genotypic component of variation for curd weight, indicating that this character can be improved by breeding. A large genotype × environment interaction included genotypic differences in stability to the environment, notably in the self-compatible genotypes. Mean curd weight and stability of genotypes to the environment for this trait were uncorrelated, indicating that high weight and high stability could be bred into a single variety.

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Approaches to rationalising selection of test environments for on-farm lentil variety trials in Mediterranean rainfed cropping systems

Australian Journal of Agricultural Research ◽

10.1071/ar05418 ◽

2007 ◽

Vol 58 (4) ◽

pp. 335 ◽

Cited By ~ 2

Author(s):

A. Sarker ◽

M. Singh ◽

F. El-Ashkar ◽

W. Erskine ◽

E. De-Pauw

Keyword(s):

Cropping Systems ◽

Genotypic Differences ◽

Environment Interaction ◽

Local Cultivar ◽

Genotype Environment Interaction ◽

Genotype Cluster ◽

Yield Responses ◽

Temporal Interactions ◽

On Farm ◽

Selection Of

This study focused on various approaches to rationalising the selection of test environments using on-farm trial data from 5 lentil (Lens culiniaris Medikus subsp. culinaris) genotypes. It was conducted over 3 years in 30 environments across 16 locations in Syria. There was maximum discrimination in the ratio of between-cluster to within-cluster variances, based on genotype yield responses to the environments. Four clusters represented the test locations, reflecting a gradient in the levels of yield and seasonal rainfall. We observed significant genotypic differences and genotype × environment interactions. Genotype × cluster interaction accounted for a substantial portion of the genotype × environment interaction. This supported a reduction in the number of test locations to evaluate genotype and environment interaction. Temporal interactions were either low or insignificant. The improved lines produced stable and significantly higher yields than the local cultivar. The structure of the clusters formed indicated the presence of research stations in each cluster. We recommend that locations for future on-farm testing should include one research location and a farmer field in each cluster (or the mega-zone) so formed. Climatic variables or geographical nearness cannot replace the role of genotype response when rationalising test locations.

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Genotype, genotype × environmental and environmental effects on grain yield and related characters of cowpea (Vigna unguiculata (L.) Walp.)

Australian Journal of Agricultural Research ◽

10.1071/ar9770609 ◽

1977 ◽

Vol 28 (4) ◽

pp. 609 ◽

Cited By ~ 4

Author(s):

W Erskine ◽

TN Khan

Keyword(s):

Grain Yield ◽

Environmental Effects ◽

Soil Conditions ◽

Environment Interaction ◽

Plant Seed ◽

Genotype Environment Interaction ◽

Two Factors ◽

Tropical Areas ◽

Joint Regression Analysis ◽

Pod Length

Genotypic, environmental and genotype x environmental interaction variances of grain yield and related characters were estimated in six diverse lowland environments in Papua New Guinea. The genotypic variance of grain yield for six diverse genotypes accounted for only 0.2% of overall variance and was not significant against genotype x environment interaction. The relative merits of alternative selection criteria, viz. pod number per plant, seed number per pod, mean seed weight, pod length and main stem height were assessed. Environmental effects of grain yield accounted for 82% of total variance, and two factors associated with moisture and soil conditions were isolated as the major causes of this variation. Genotype × environment interaction effects were analysed by joint regression analysis, and the applicability of the analysis to tropical areas with low levels of management is discussed.

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Additive-multiplicative approximation of genotype-environment interaction.

Genetics ◽

10.1093/genetics/138.4.1339 ◽

1994 ◽

Vol 138 (4) ◽

pp. 1339-1349 ◽

Cited By ~ 1

Author(s):

A Gimelfarb

Keyword(s):

Drosophila Melanogaster ◽

Environmental Effects ◽

Experimental Evaluation ◽

Quantitative Traits ◽

Directional Selection ◽

Environment Interaction ◽

Broad Sense Heritability ◽

Degree Polynomial ◽

Environmental Variance ◽

Genotype Environment Interaction

Abstract A model of genotype-environment interaction in quantitative traits is considered. The model represents an expansion of the traditional additive (first degree polynomial) approximation of genotypic and environmental effects to a second degree polynomial incorporating a multiplicative term besides the additive terms. An experimental evaluation of the model is suggested and applied to a trait in Drosophila melanogaster. The environmental variance of a genotype in the model is shown to be a function of the genotypic value: it is a convex parabola. The broad sense heritability in a population depends not only on the genotypic and environmental variances, but also on the position of the genotypic mean in the population relative to the minimum of the parabola. It is demonstrated, using the model, that G x E interaction may cause a substantial non-linearity in offspring-parent regression and a reversed response to directional selection. It is also shown that directional selection may be accompanied by an increase in the heritability.

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Integrating Multivariate and Univariate Statistical Models to Investigate Genotype–Environment Interaction of Advanced Fragrant Rice Genotypes under Rainfed Condition

Sustainability ◽

10.3390/su13084555 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4555

Author(s):

Norainy Hashim ◽

Mohd Y. Rafii ◽

Yusuff Oladosu ◽

Mohd Razi Ismail ◽

Asfaliza Ramli ◽

...

Keyword(s):

High Stability ◽

Block Design ◽

Univariate Analysis ◽

Primary Objective ◽

Environment Interaction ◽

Fragrant Rice ◽

Commercial Cultivation ◽

Genotype Environment Interaction ◽

Premium Price ◽

Second Category

Specialty fragrant rice is sold at a premium price in both local and international trade because of its superior grain qualities. In this research, 40 advanced fragrant rice accessions were evaluated in different environments. The primary objective was to identify genotypes with high grain yield and high stability using multivariate (GGE biplot) and univariate analysis (regression slope, deviation from regression, Shukla’s stability variance, Wricke’s ecovalence, and Kang’s stability statistic). The field experiment trials were laid in a randomized complete block design in three replications. The analysis of variance showed highly significant differences among genotypes, locations, seasons, and the interactions between genotype, locations, and seasons. The environment significantly explained about 43.32% (37.01 and 6.31% for locations and seasons) of the total sum of squares. Based on average ranking generated from multivariate and univariate stability measured, rice accessions were classified into three major categories, viz., genotypes having high trait performance, and high stability as category 1. The second category consists of genotypes that exhibit high mean performance but low stability, while the third category includes genotypes with high stability but low trait performance. Our results showed that breeding for yield performance was possible, and the identified genotypes could be recommended for commercial cultivation.

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