|ZHENG, XIUTING - Texas A&M University|
|WANG, FEI - Texas A&M University|
|HOEGENAUER, KEVIN - Texas A&M University|
|ASHRAFI, HAMID - University Of California|
|STELLY, DAVID - Texas A&M University|
|Bell, Alois - Al|
|VAN DEYNZE, ALLEN - University Of California|
|JONES, DON - Cotton, Inc|
|NICHOLS, ROBERT - Cotton, Inc|
Submitted to: Plant and Animal Genome
Publication Type: Abstract Only
Publication Acceptance Date: 9/8/2012
Publication Date: 1/17/2013
Citation: Zheng, X., Wang, F., Hoegenauer, K.A., Quintana, J., Ashrafi, H., Stelly, D., Bell, A.A., Van Deynze, A., Jones, D.C., Nichols, R.L. 2013. Resolving tight linkages a round renion by MAS for high-resolution recombination in chromosome-11. Plant and Animal Genome XXI, January 12-16, 2013, San Diego, California. p. 453.
Technical Abstract: Reniform (Rotylenchulus reniformis) nematodes cost US cotton growers over $130M per year. Extremely strong resistance was found in the wild African diploid species G. longicalyx and introgressed into tetraploid cotton. Two highly resistant cotton lines were released. LONREN-1 and LONREN-2, but field testing revealed severe stunting of seedlings grown in fields heavily infested with reniform nematodes. Possible explanations include  root damage caused by hypersentivity to the nematode and  loss of one or more linked (repulsion) G. hirsutum loci that affect susceptibility to soil-borne pathogen(s), e.g. Thielaviopsis, which interact synergistically with the nematode to cause more severe stunting. Numerous nematode and fungal resistance loci of cotton are known to reside in chromosome 11. To better characterize this chromosomal region and potentially separate the resistance and stundting, we have mounted a map-based approach to recover recombinants that retain the alien resistance gene (Renlon) but minimize the flanking alien segments. To exploit this strategy at high resolution, we are saturating this region by developing SNP markers for G. longicalyx, and localizing those in the alien segment region. Hundreds of Gl-Gh SNPs have been aligned to this region according to D5 genome. And some SNPs have been tested and found to be linked with Renlon. The SNPs will then be used on large populations developed from different resistance families by using resistance-linked SSR markers BNL3279, BNL1231, CIR069 to recover recombinants closely flanking the alien resistance gene, as well in nearby regions. The most closely flanking recombinants will be phenotyped for resistance, stunting and tested for agronomic performance.