Enhancing salinity tolerance in rice using sexual and somatic hybrids of Oryza sativa and Porteresia coarctata.

Widespread soil salinity is an increasing problem in regions of rice cultivation since this major environmental stress limits rice productivity. Numerous studies conducted on biochemical and molecular aspects have shown that the ability of plants to tolerate water stress and salinity is determined by multiple biochemical pathways that facilitate retention and/or acquisition of water, protect chloroplast functions, and maintain ion homeostasis. This abiotic stress is under polygenic control and a combination of approaches is required to achieve the goal of increased tolerance for water stress and salinity. These approaches include the collection of tolerant genotypes to be used as a source of new genes and conventional breeding and selection measures. Also required are novel molecular and biotechnological methodologies to identify stress-related genes and to use them as probes for selecting tolerant genotypes and for producing transgenic plants. Functional genomic studies, QTL analysis and screening, and the use of somatic cell genetics will be involved.