Submitted to: Euphytica
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/15/2007
Publication Date: 2/7/2007
Citation: Abdurakhmonov, I.Y., Buriev, Z.T., Saha, S., Pepper, A.E., Musaev, J.A., Almatov, A., Shermatov, S.E., Kushanov, F.N., Mavlonov, G.T., Reddy, U.K., Yu, J., Jenkins, J.N., Kohel, R.J., Abdukarimov, A. 2007. Microsatellite markers associated with lint percentage trait in cotton, Gossypium hirsutum. Euphytica. 156:141-156. Interpretive Summary: Molecular markers associated with fiber traits have the potential to play a key role in understanding of cotton fiber development and marker assisted selection (MAS). Seventy-six intraspecific RI lines of G. hirsutum derived from the cross between L-70 (fuzzless/lintless with 0% lint on cottonseed) and L-47 (fuzzy/linted with 41-43% lint on cottonseed) lines and parental lines were used in molecular mapping of lint% with 262 simple sequence repeat (SSR) markers. Results revealed several SSR markers are associated with lint%. Several of these SSR markers are EST-SSR markers associated with functional genes. Our results demonstrated that marker TMB0366 associated with a lint percentage QTL was located on the long arm of chromosome 26. Another lint percentage associated marker, TMB00471, was assigned to the chromosome 12. Chromosomes 12 and 26 in cotton are considered homeologous chromosomes in tetraploid cotton (AD genome). These markers have potential for MAS and map based cloning of important fiber related genes.
Technical Abstract: Molecular markers associated with fiber development traits have the potential to play a key role in understanding of cotton fiber development. Seventeen SSRs out of 304 markers tested from MGHES (EST-SSR), JESPR (genomic SSR), and TMB (BAC-derived SSR) collections showed significant linkage associations (using a Kurskal-Wallis non-parametric test) with lint percentage QTL in a set of recombinant inbred cotton lines (RIL) segregating for lint percentage. The permutation test of these potential markers associated with fiber development QTL determined that 12 SSR markers have stable estimates, exceeding empirically acquired threshold values at or above a=0.01. These markers, in particular fiber-specific EST-SSRs, might be the possible candidate loci contributing for fiber development in cotton. Detail sequencing analysis of MGHES-31 revealed that this EST had several novel allelic variations in intraspecific recombinant inbred lines (RILs) compared to the parents. In this RIL individual MGHES-31 microsatellite had alleles with 7, 8, 9, 10, 11 CAT repeats. In addition, several SNP mutations in sequences flanking the microsatellite repeat separated MGHES-31 alleles into two well-supported A- and D-genome derived phylogenetic groups, suggesting existence of two different genes in tetraploid cottons. The MGHES-31 EST was strongly associated with fiber development QTL with expanded alleles of 9-11 CAT repeats. The BLAST analysis of MGHES-55, a marker strongly associated with lint percentage, revealed strong similarity to cotton boll abscission EST sequences, implying the potential association of abscission-like factors in fiber cell development. Several lint percentage QTL associated SSR markers have been located to specific chromosomes using deletion analysis in aneuploid chromosome substitution lines of cotton. Outcomes of the work may prove useful in understanding and revealing the molecular basis of the fiber development, and the utilization of these markers for development of superior cotton cultivars through marker-assisted selection (MAS) programs.