QTL mapping for flowering-time and photoperiod insensitivity of wild cotton Gossypium darwinii Watt

Authors: KUSHANOV, FAKHRIDDIN - Uzbekistan Academy Of Sciences; BURIEV, ZABARDAST - Uzbekistan Academy Of Sciences; SHERMATOV, SHUKHRAT - Uzbekistan Academy Of Sciences; TURAEV, OZOD - Uzbekistan Academy Of Sciences; NOROV, TOKHIR - Uzbekistan Academy Of Sciences; PEPPER, ALAN - Texas A&M University; Saha, Sukumar; Ulloa, Mauricio; Yu, John; Jenkins, Johnie; ABDUKARIMOV, ABDUSTATTOR - Uzbekistan Academy Of Sciences; ABDURAKHMONOV, IBROKHIM - Uzbekistan Academy Of Sciences

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/27/2017
Publication Date: 10/9/2017
Citation: Kushanov, F., Buriev, Z.T., Shermatov, S.E., Turaev, O.S., Norov, T., Pepper, A.E., Saha, S., Ulloa, M., Yu, J., Jenkins, J.N., Abdukarimov, A., Abdurakhmonov, I.Y. 2017. QTL mapping for flowering-time and photoperiod insensitivity of wild cotton Gossypium darwinii Watt. PLoS One. https://doi.org/10.1371/journal.pone.0186240.
DOI: https://doi.org/10.1371/journal.pone.0186240

Interpretive Summary: In order to transfer valuable genes from most wild and semi-wild species, sensitive to photoperiodism, the breeders will have to overcome the barrier of photoperiodism and flowering aasociated with the wild species. A molecular map on photoperiodism and flowering will help to improve knowledge on the gene(s) controlling photoperiodism and flowering. Selection of DNA markers physically adjacent to the alleles associated with photoperiodism and flowering help breeder in the genetic manipulation in a marker assisted selection program to transfer valuable genes in the genetic improvement of Upland cotton. For the purpose of molecular mapping of quantitative trait loci (QTLs) controlling flowering, a bi-parental cotton population segregating for photoperiodic flowering was developed by crossing a photoperiod insensitive irradiation mutant line with its pre-mutagenesis photoperiodic wild-type G. darwinii Watt genotype. Individuals from the F2 and F3 generations were grown with their parental lines and F1 hybrid progeny in the long day and short night summer condition (natural day-length) of Uzbekistan to evaluate photoperiod sensitivity, i.e., flowering-time during the seasons 2008-2009. Through genotyping with DNA markers the individuals of this bi-parental population segregating for flowering-time, linkage maps were developed using 212 simple sequence repeat (SSR) and three cleaved amplified polymorphic sequence (CAPS) markers. Six QTLs directly associated with flowering-time and photoperiodic flowering were discovered in the F2 population, whereas eight QTLs with flowering-time and photoperiodic flowering were detected in the F3 population. The outcome of this research will expand our understanding of the genetic and molecular mechanisms of photoperiodic flowering. Identified markers should be useful for marker assisted selection in cotton breeding to improve early flowering characteristics.

Technical Abstract: Most wild and semi-wild species of the genus Gossypium are sensitive to photoperiodism. The wild germplasm cotton collection is a valuable source of genes for genetic improvement of current cotton cultivars. For the purpose of identifying quantitative trait loci (QTLs) controlling flowering, a bi-parental cotton population segregating for photoperiodic flowering was developed by crossing a photoperiod insensitive irradiation mutant line with its pre-mutagenesis photoperiodic wild-type G. darwinii Watt genotype. Individuals from the F2 and F3 generations were grown with their parental lines and F1 hybrid progeny in the long day and short night summer condition (natural day-length) of Uzbekistan to evaluate photoperiod sensitivity, i.e., flowering-time during the seasons 2008-2009. Through genotyping the individuals of this bi-parental population segregating for flowering-time, linkage maps were constructed using 212 simple sequence repeat (SSR) and three cleaved amplified polymorphic sequence (CAPS) markers. Six QTLs directly associated with flowering-time and photoperiodic flowering were discovered in the F2 population, whereas eight QTLs were identified in the F3 population. Two QTLs controlling photoperiodic flowering and duration of flowering were common in both populations. In silico annotations of the flanking DNA sequences of mapped SSRs from sequenced cotton (G. hirsutum L.) genome database has identified several potential ‘candidate’ genes that are known to be associated with regulation of flowering characteristics of plants. The outcome of this research will expand our understanding of the genetic and molecular mechanisms of photoperiodic flowering. Identified markers should be useful for marker assisted selection in cotton breeding to improve early flowering characteristics.