Plant Genomics

Biography

Biography: Rakesh K

Abstract

    Rice     responds differentially at different stages of development.  The    seedling    and  reproductive stages are the most sensitive growth stages with very weak as sociation, suggesting that they are regulated by different processes and sets of    genes   /QTLs. There are hardly any studies exist on reproductive-stage salinity toleranc e mainly because of the lack of reliable reproductive-stage-specific    phenotyping    techniques and incomplete knowledge of the stage-specific mechanisms of salinity tolerance.Two major challe nges for screening exclusively for the reproductive stage are, 1) how to stress   plants   at the reproductive stage without stressing them at the  seedling  or late  vegeta  tive stage ; and 2) how to impose the stress on di  fferent  genotypes  or mapping populations at e quivalent growth stages of development because of the variability in the progression of growth rate through developmental stages. We standardise a methodology that allows salt     translocation     to the reproductive organs such as the flag leaf (the largest source for the sink) and panicle as quickly as possible just at the initiation of booting when the    genotypes    are at the same stage of tissue/organ development rather depending on age of the   plant  . A  mapping  population derived from CSR28/Sadri was used QTL identification using the novel  phenot ypin  g  technique and 6K illumina SNP platform. Salt stress equivalent to EC 10 dSm-1 was imposed on  rice plants  with trimmed leaves starting from boot leaf emergence up to 20 days in an experiment. Stage-specific effect of salt stress was verified by observing s alt-sensitive and salt-tolerant genotypes. Details will be presented.