Cruet-Burgos, Clara M.

Profile Picture

Filters

20181
Reset filters

Settings

Citations

Publication Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Publication
    Genome mapping of anthracnose resistance in sorghum germplasm
    (2018) Cruet-Burgos, Clara M.; Siritunga, Dimuth; College of Arts and Sciences – Sciences; Montalvo, Rafael; Cuevas, Hugo E.; Department of Biology; Beaver, James
    Sorghum [Sorghum bicolor (L.) Moench] is the fifth most produced cereal in the world with increasing popularity by its ability to grow on marginal lands with minimal input of water and nutrients. Nevertheless, sorghum production is limited by foliar diseases such as anthracnose that can cause yield loses of up to 50% in susceptible varieties. Although several resistance sources have been identified in multiple sources of germplasm, the lack of inheritance studies limits their effective use in sorghum breeding programs. Therefore, three populations of recombinant inbred lines (RILs) derived from the crosses between resistant lines IS18760, QL3 or SC112-14 with the susceptible line PI609251 were evaluated for anthracnose reaction in Texas, Florida, Georgia and Puerto Rico. In parallel, three high density linkage maps based on genotype by sequence analysis were constructed to identify quantitative trait loci (QTL) for resistant response. The IS18760 and QL3 RILs populations showed segregation for anthracnose resistance in Texas and Puerto Rico, and susceptibility against pathotypes from Florida and Georgia, while SC112-14 segregated in the four locations. Genome scan of IS18760 by composite interval mapping detected 4 QTL in Texas and 4 QTL in Puerto Rico, while the scan of QL3 detected 4 QTL in Puerto Rico. Both analyses resulted in the detection of one QTL of 1.63 Mb in chromosome 4 that accounted for 22% and 9% of the phenotypic variation in Texas and Puerto Rico. The genome scan of SC112-14 identified one QTL in chromosome 5 (Cs-SC112) that explained 0.51, 0.57, 0.37 and 0.52% of the phenotypic variance in Puerto Rico, Texas, Florida and Georgia, respectively. Subsequently, analysis of 1,500 F2:3 segregating individuals reduced Cs-SC112 locus to an interval of 23 Kb enclosing three candidate genes. Comparative analysis with Plant Resistance Gene Database suggested Sobic.005g172300, which is characterized by the presence of F-box and Ser-Thr kinase domains, is the best candidate gene in the locus. Resequencing analysis of both parental lines identified four point mutations that generate two protein variants. Candidate genes within these loci suggest that resistance response is controlled by multiple defense mechanisms including signaling cascades and transcriptional reprogramming genes. The inheritance information and molecular markers developed in this study can facilitate the use of these resistant sources in breeding programs.