Development of Superior Fibre Quality Upland Cotton Cultivar Series ‘Ravnaq’ Using Marker-Assisted Selection

Abstract

Marker-assisted selection (MAS) helps to shorten breeding time as well as reduce breeding resources and efforts. In our MAS program, we have targeted one of previously reported LD-blocks with its simple sequence repeat (SSR) marker(s), putatively associated with, at least, four different fibre quality QTLs such as fibre length, strength, micronaire and uniformity. In order to transfer targeted QTLs from a donor genotype to a cultivar of choice, we selected G. hirsutum donor genotypes L-141 and LN-1, possessing a fibre quality trait-associated LD-block from the chromosome 7/16. We crossed the donor lines with local elite G. hirsutum cultivars ‘Andijan-35’ and ‘Mekhnat’ as recipients. As a result, two segregating populations on LD-block of interest containing fibre QTLs were developed through backcrossing (BC) of F1 hybrids with their relative recipients (used as recurrent parents) up to five generations. In each BC and segregating BC1-5F1 populations, a transfer of targeted LD-block/QTLs was monitored using a highly polymorphic SSR marker, BNL1604 genotype. The homozygous cultivar genotypes with superior fibre quality and agronomic traits, bearing a targeted LD-block of interest, were individually selected from self-pollinated BC5F1 (BC5F2–5) population plants using the early-season PCR screening analysis of BNL1604 marker locus and the end-of-season fibre quality parameters. Only improved hybrids with superior fibre quality compared to original recipient parent were used for the next cycle of breeding. We successfully developed two novel MAS-derived cotton cultivars (named as ‘Ravnaq-1’ and ‘Ravnaq-2’) of BC5F5 generations. Both novel MAS cultivars possessed stronger and longer fibre as well as improved fibre uniformity and micronaire compared to the original recurrent parents, ‘Andijan-35’ and ‘Mekhnat’. Our efforts demonstrated a precise transfer of the same LD-block with, at least, four superior fibre QTLs in the two independent MAS breeding experiments exploiting different parental genotypes. Results exemplify the feasibility of MAS in cotton breeding.

Molecular genetic diversity in relation to the quantitative and qualitative (fiber quality) traits in upland cotton (Gossypium hirsutum L.)

“…4). Similarly, the alleles of the marker BNL1604 showed signi cant differences in between them for the trait UHML as reported by Darmanov et al (2022).…”

First Report on Development of Genome-Wide Microsatellite Markers for Stock (Matthiola incana L.)

“…It has been discovered that SSRs are ubiquitous in genomes, with repeat units of 1–6 nt. As the most useful DNA marker system for variety identification and germplasm management, SSR molecular markers have several advantages due to their abundance, high polymorphism, multiple alleles, co-dominance, low-cost, and the ease of assay by PCR [ 17 , 18 ], which have been applied extensively in genetic analysis, such as the analysis of population structure and genetic diversity [ 19 , 20 ], QTL mapping [ 21 , 22 , 23 ], marker-assisted selection breeding [ 24 , 25 , 26 ], and DNA fingerprinting [ 27 , 28 ], etc. SSR molecular markers are rarely used in M. incana [ 11 , 14 ], which is largely due to the fact that SSR molecular markers have not been developed in M. incana .…”

Effects of Rhizobacteria on Agronomic Traits of Two Gossypium hirsutum Cotton Varieties

“…Ravnaq-1 cotton cultivar derived through MAS technology by selecting homozygous samples among the BC5F5 (Andijan-35×L-141) segregation hybrids using the BNL1604 marker that is associated with fibre length and strength 26 .…”