Author
LIU, YAN - University Of Arkansas | |
Jia, Yulin | |
QI, XINSHUAI - Washington University | |
OLSEN, KENNETH - Washington University | |
CAICEDO, ANA - University Of Massachusetts | |
Gealy, David |
Submitted to: APS Annual Meeting
Publication Type: Abstract Only Publication Acceptance Date: 8/1/2014 Publication Date: 8/9/2014 Citation: Liu, Y., Jia, Y., Qi, X., Olsen, K.M., Caicedo, A.L., Gealy, D.R. 2014. Insights into molecular mechanism of blast resistance in weedy rice. Proc. APS-CPS Joint Meet., Minneapolis, MN, pp.67-70. August 9-13, 2014. Interpretive Summary: Technical Abstract: Weedy rice is a serious pest in direct-seeded rice fields in the U.S. and worldwide. Under suitable conditions, weedy rice can reduce crop yields up to 70%. However, weedy rice may carry novel disease resistance genes. Rice blast disease caused by the fungus Magnaporthe oryzae is a major disease worldwide. In the present study, blast resistance genes were investigated with two recombinant inbred line (RIL) populations consisting of 175 and 224 individuals (S and B populations), respectively, derived from crosses of two U.S. weedy rice ecotypes, the straw hull type PI653435 (1135-01, RR9) and the black hull type PI653419 (1996-9, RR20), with a closely related Asian indica rice variety Dee Geo Woo Gen (DGWG). Genotypes of all individuals in the F5 generation were determined using the Genotype by Sequencing (GBS) method. Two high resolution genetic maps with 6179 single nucleotide polymorphism (SNPs) in the S population and 14382 SNPs in the B population, respectively, were constructed. Disease reactions of three parental lines were evaluated with 14 U.S. races/isolates in a greenhouse. Two weedy rice ecotypes showed partial resistance to several U.S. isolates. Disease reactions of all individuals of both populations to the races (isolates) IC17 (ZN57), IE1 (ZN13), IE1K (TM2), ID1 (ZN42) and IB33 (FL9, a laboratory strain) were determined in a greenhouse. Resistance genes to blast were mapped using R/qtl software. The candidate resistance genes were identified from genomic regions delimited by SNPs markers. Insights into the molecular mechanism of blast resistance in weedy rice will be presented. |