Agricultural and Biological Research

Conserved markers order in quantitative trait loci confers resistance against black root rot disease in cotton

AnhPhu Nam Bui

Background and Objective: Black root rot, incited by the soil borne fungus Thielaviopsisbasicola, can cause substantial yield loss and reduced fiber quality in cotton (Gossypium spp.). The isolation of candidate resistant genes in tetraploid genome AADD cotton species (2n=4x=52) remains challenging in the absence of research of black root rot resistance on progenitor DD genome diploid cotton (G. raimondii). In this study, by exploiting Phytozome database, a comparative map of the black root rot-resistance quantitative trait loci in DD genome was constructed. Materials and methods: Simple sequence repeats markers associated with these three quantitative trait loci in the AA genome were used as “anchoredprobes” frameworks for establishing relationships between the two cotton genomes AA and DD. Results: Our results showed that there was colinearity between the genetic map of simple sequence repeats markers on AA genome and the physical map of these simple sequences repeats markers on DD genome. It was suggested that the syntenic loci on chromosome 2, 7 and 11 on DD genome could correspond the black root rot resistance. Conclusion: This study could serve as a fundamental step in isolating and introducing the resistance gene against black root rot into elite cotton cultivars