Key points are not available for this paper at this time.
Abstract Background: Cotton is a unique and notable cash crop of India occupying first place in the world’s ranking with an acreage of 130.61 lakh hectares area i.e. around 40% of the world's area (324.16 lakh hectares) whereas, in productivity, India occupied 39th rank with an average yield of 447 kg/ha. The main reason for less productivity is most of the cotton cultivation is under rainfed conditions (https://ministryoftextiles.gov.in/annual-report-2022-2023). Hence, there is an immense need to develop high-yield varieties or hybrids which give higher yields. Therefore, the current investigation was executed to evaluate the association among yield and its attributing traits, genetic variations, genetic diversity of yield and its related traits, fiber quality traits along with sucking pest tolerance in cotton, and to evaluate the associations existing among the elite lines. Results: Analysis of variance manifested a substantial variation for all studied traits boll weight, seed index, and lint yield. It was noticed that the evaluations of phenotypic variances were a little higher than genotypic variances for many of the characters and observed low environmental variances indicating a lesser amount of influence of environment on these traits. Direct selection can be practiced in heterosis breeding on lint yield, seed cotton yield/ha, plot weight, number of monopodia/plant, number of bolls/plant, micronaire, number of sympodia/plant and lint index as these traits showcased a high heritability coupled with high genetic advance per percent mean (GAM). The association studies discovered that the seed cotton yield/ha manifested a positive significant kinship with plant height (0.91), number of sympodia/plant (0.87), number of bolls/plant (0.96), boll weight (0.91), lint yield (0.94), GOT (%) (0.72), plot weight (0.98) and uniformity index (UHML) (0.48) signifying that the surge in seed cotton yield is due to increase in one or more of the above traits. Three principal components (PCs) out of sixteen PCs manifested eigenvalues (> 1) with a maximum share of the total variability (80.93%). The traits lint yield, lint index, seed cotton yield, plot weight, number of bolls/plant, boll weight, plant height, number of sympodia/plant, ginning out turn, seed index, and uniformity index contributed maximum share to the total divergence. Wide genetic divergence was observed between clusters IV and IX (1621.59) followed by clusters IV and VI (1178.50) and clusters IV and X (1031.41). Conclusion Based on PCA about the D2 analysis the elite lines LH Bt Cotton − 7, 8, 12, 27, 22, 20, 24, 2, 17, 11, 14, 26, and 20 were found to be genetically diverse. Hence, these lines can be exploited in future breeding programs to develop better-performing varieties/hybrids and also for breeding for advanced lines.
Chapara et al. (Thu,) studied this question.