Executive Summary : | Rice, a staple food, is severely impacted by environmental stresses like drought and salinity. salinity is caused by excess salts in soil and irrigation water, which are absorbed by root hairs and move radially through the roots. Rice plants require sodium ions for normal metabolic reactions, while potassium ions are needed for normal reactions. Reducing sodium accumulation and enhancing potassium uptake is crucial for survival under salt stress environments. A low cytosolic Na/K ratio is considered a key salt tolerance trait. The sALTOL locus is one of the major salt tolerant QTLs mapped on chromosome 1 in IR29/Pokkali recombinants. Further analysis revealed that OsHKT1;5 belongs to the high affinity potassium transporter (HKT) family and has a Na+-selective transport function. Other HKT family members, OsHKT1;1, return sodium ions from leaf blades to roots through phloem tissue. Molecular studies have established the roles of major regulatory proteins calcineurin B like protein 9, calcineurin B like interacting protein kinases 23, and high affinity potassium transporter 5 in potassium uptake under salt stress in Arabidopsis and rice. The proposed investigation aims to assemble key candidate genes involved in regulating Na/K homeostasis under salt stress in a recombinant population derived from a highly salt tolerant land race Pokkali with AsD16, an elite salt sensitive cultivar. The F2 plant(s) harboring favorable alleles for the five selected candidates will be identified. Evaluation of physiological, morphological, and agronomic performance will be taken up through F3, F4, and F5 generations under in vitro and salt-affected target field environments. |
Co-PI: | Prof. Manonmani swaminathan, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu-641003, Dr. Jeyaprakash Paramasiwam, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu-641003, Dr. Veersamy Ravichandran, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu-641003 |