Development of Salt-Tolerant Rice Varieties to Enhancing Productivity in Salt-Affected Environments

Abstract

Among abiotic stresses, salt stress is the most complicated problem posing a major challenge for maintaining world food supplies as well as food security as it covers 1125 m ha globally and 6.73 m ha in India. It is very essential to increase rice productivity in salt-affected soils for food security and sustainability in salt-affected environments. The pass port data of 9000 rice Germplasm has been established for 30 traits and a mini core of 1500 lines has been developed. Approximately 20,000 rice lines have been screened for salinity and sodicity for both seedling and reproductive stages. The highly tolerant rice lines are being used in breeding programme to enhance the genetic diversity. The six QTLs in chromosomes 1, 2, 8, 9, 10 has been identified for the Na/K ratio, spikelet fertility and grain yield for the reproductive stage salt tolerance. The Saltol QTL has been transferred to Indian mega rice varieties namely, Pusa44 and Sarjoo52, to improve the salinity tolerance at the seedling stage. Similarly, the qSSISFHS8.1 (QTL for spikelet fertility) QTL is being transferred into mega rice varieties namely, PR114, Pusa44 and Sarjoo52, to improve the salinity tolerance at the reproductive stage. The marker assisted selection accelerates the breeding activities to develop the salt-tolerant varieties as well as transfer the QTLs to HVYs through marker assisted back cross breeding. The Central Soil Salinity Research Institute (CSSRI) has developed 13 salt-tolerant rice varieties, namely CSR10, CSR13, CSR23, CSR27, Basmati CSR30, CSR36, CSR43, CSR46, CSR49, CSR52, CSR56, CSR60 and CSR76, through conventional breeding approaches to increase the productivity of salt-affected soils for resource poor farmers. The popularity of these salt-tolerant rice varieties can be ascertained from the facts that large quantity of breeder seeds (1056 quintals) and truthfully labelled seeds (3126 quintals) has been produced and sold during last 22 years (2000–2021), more demand from the farmers and large area app. One point two million hectares is covered by these salt-tolerant rice varieties every year. Numerous salt-tolerant rice lines are being developed at CSSRI to cope with salt-affected soils and enable sustainable agriculture under salt-affected soils.

Keywords

• rice
• salinity
• sodicity