Implications of correlations and genotype by environment interactions among cotton traits

Abstract

The existence of negative correlations, coupled with significant genotype x environment interaction (GE) among cotton traits poses both opportunities and challenges in breeding. This study aimed at determining the existence of GE on seed cotton (Gossypium hirsutum L.) yield, lint yield, earliness index, gin out turn ratio, 100 seed weight, split boll weight and fuzz grade and correlations, among these traits, as well as understanding the implications on variety evaluation and release. Ten genotypes from Cotton Research Institute, Zimbabwe, were evaluated across seven locations, during the 2012/13 and 2013/14 cropping years with three replications at each location. Seed cotton and lint yield, earliness index, gin out turn ratio, 100-seed weight, split boll weight and fuzz grade were measured on the genotypes at all locations. Analysis of variance for GE showed significant differences (P<0.05) on most traits, except earliness index. There were huge GE and error variance components on seed cotton yield and allied traits that reduced heritability and correlation among these traits. Seed cotton and lint yield were significantly correlated (P<0.001; r = 0.95) to each other; while split boll weight had significant correlation (P<0.004; r = 0.82) with 100-seed weight. The genotype plus GE biplot analysis showed that SZ 9523 had high and stable yield and desirable fuzz grade, which made it an ideal genotype for release. All locations belonged to one complex mega-environment with Chisumbanje Research Station more representative and most discriminating location which can be used in early generation testing of cotton.

Heritability and correlation analysis of morphological and yield traits in genetically modified cotton

“…In addition, the yield of seed cotton was positively linked with plant height, sympodial branches, monopodial branches, and bolls per plant whereas negatively correlated with days to 1 st flowering. While seed cotton yield had a positive correlation with 100-seed weight, the number of bolls per plant, plant height, and boll weight (Memon et al 2017;Mukoyi et al 2018). Lint index, number of bolls per plant, boll weight, sympodial branches per plant, and GOT exhibited positive linkage with the yield of seed cotton per plant.…”

Heritability and correlation analysis of morphological and yield traits in genetically modified cotton

“…In addition, yield of seed cotton was positively linked with plant height, sympodial branches, monopodial branches and bolls per plant whereas negatively correlated with days to 1 st owering. While seed cotton yield had positive correlation with 100-seed weight, number of bolls per plant, plant height and boll weight (Memon et al, 2017;Mukoyi et al, 2018). Lint index, number of bolls per plant, boll weight, sympodial branches per plant and ginning outturn (GOT) exhibited positive linkage with yield of seed cotton per plant.…”

Heritability and correlation analysis of morphological and yield traits in genetically modified cotton

“…In addition, yield of seed cotton was positively linked with plant height, sympodial branches, monopodial branches and bolls per plant whereas negatively correlated with days to 1 st owering. While seed cotton yield had positive correlation with 100-seed weight, number of bolls per plant, plant height and boll weight (Memon et al, 2017;Mukoyi et al, 2018). Lint index, number of bolls per plant, boll weight, sympodial branches/plant and GOT exhibited positive linkage with yield of seed cotton per plant.…”