Plant & Animal Genomes XVI Conference Plant & Animal Genomes XVI ConferenceJanuary 12-16, 2008
Town & Country Convention Center
San Diego, CA
Drought frequently occurs in late stages of growth and development of rice and causes significant yield loss. We have integrated approaches including germplasm screening, genetic analysis and marker-assisted selection, functional genomics, and transgenics to identify germplasms or genes for improving drought resistance of rice. Progresses will be presented in the meeting as outlined in the followings. 1) Germplasm screening. More than 10000 T-DNA insertion mutant families and about 200 condensed core collection of rice germplasms have been screened under drought conditions at vegetative or reproductive stages. A few mutants that were more sensitive or tolerant to drought stress than the wild type have been identified. A few drought resistant germplasms were added to the backcross breeding programs. 2) Genetic analysis and near isogenic lines. Based on genetic mapping of drought resistance, Marker-assisted selection has been used to introduce alleles of drought resistance QTLs from upland rice IRAT109 to irrigated rice Zhenshan 97. More than 20 near isogenic lines for drought resistance-related QTLs have been generated and tested. 3) Genomic expression profiling. Using Affymetrix DNA chip, genomic expression profiles have been surveyed for rice cultivars under drought (cv. IRAT109 and Zhenshan 97), cold (10 cultivars or cold-tolerant landraces), salt (10 cultivars or salt-tolerant landraces), and ABA (Zhonghua 11 and ABA-insensitive mutant) stresses. Thorough analysis of expression profiling data provided very useful information for selecting candidate genes for transgenic testing. 4) Functional analysis of genes conferring stress resistance in rice. Nearly 100 stress-inducible rice genes have been over-expressed in rice cultivar Zhonghua 11 to test their effect on stress resistance. A few regulatory genes have been functionally characterized. 5) Molecular breeding of drought resistance of rice. A few function-known genes were transformed into rice to identify genes conferring drought resistance at reproductive stage. Experience and perspective of genomic and transgenic approaches on stress resistance improvement will be discussed in the meeting.