Molecular mapping of QTLs for fiber quality traits in Gossypium hirsutum multi-parent recombinant inbred lines

Abstract

Cotton is a valuable ber crop which supplies raw material to more than 50 industries and is produced in more than 70 countries worldwide thus, it is worthy of its reputation as "white gold". The superiority of cotton ber over other crops is primarily dependent on its quality. However, further improvements in ber length, strength and neness are required for modern processing technology and for cotton to maintain its position in the global market. Association mapping enables identi cation of QTLs controlling ber quality-related traits which can be useful in cotton breeding. In the present study, we performed genetic diversity, linkage disequilibrium and association mapping analyses in 157 G. hirsutum multi-parent recombinant inbred lines using a total of 102 SSR markers. The population had depressed genetic variability (14%), a result of inbreeding of modern cotton genotypes. Despite this, we identi ed 13 signi cant and stable marker-trait associations for seed cotton yield, lint percentage, ber length, ber strength and ber neness (p < 0.005). We also detected QTL co-localizations with positive and negative marker additive effects. Our results indicate that selection against negative alleles may be as important as selection for positive alleles. Analysis of the effects of allelic combinations at different QTLs revealed signi cant and stable marker clusters that can be selected for or against to provide maximum quality gains in cotton ber quality.

Genetic analysis of heat tolerance in hot pepper: insights from comprehensive phenotyping and QTL mapping

“…The identification of co-localized quantitative trait loci (QTLs) governing various heat-related traits represents a remarkable opportunity to gain profound insights into the intricate mechanisms underlying heat tolerance. Such co-localizations arise from the convergence of multiple crucial genes within the same genomic region, the presence of linkage disequilibrium, or the pleiotropic effects of specific genes (Kato et al, 2000;Baytar et al, 2021). Furthermore, the mapping of correlated traits to similar genetic locations is expected since they are likely controlled by common genetic factors, establishing an intriguing genetic architecture (Kato et al, 2000).…”

Genome-Wide Association Study of Lint Percentage in Gossypium hirsutum L. Races

“…Cotton is one of the most important cash crops, which supplies raw material to more than 50 industries globally and is extensively planted in more than 70 countries throughout the world [ 1 ]. Of the four cultivated species, upland cotton ( Gossypium hirsutum L.), a main supplier for the textile industry, contributes approximately 95% of cotton production, owing to its high yield, attractive fiber quality, and wide adaptability [ 2 , 3 ].…”