Rice (Oryza sativa L.) is an essential cereal crop which feeds more than half of the world’s population. Rice is cultivated on one-tenth of the world's arable land (approximately 150 million hectares (ha)). Its production is critically affected by salinity stress, which harms photosynthesis and growth, causing biomass loss and partial sterility. The extent of salinization of cultivable soil is increasing by 10% annually. It is predicted that more than 50% of the world's land will be damaged by salinization by 2050. In Pakistan, approximately 6.30 Mha of land is severely affected by salt stress. To cope with this problem, this study was conducted to identify saline-tolerant rice cultivars, 14 rice cultivars (PK1121 aromatic, Nonabokra, Kalomonok, PK10683, PK8892 Tol-19, Shaheen Tol-19, Chenab Tol-19, Punjab Basmati, Super Basmati 2019, Basmati 2000, Basmati 370, Basmati 385, Super Basmati, and Basmati 515 Tol-19) were grown in a 5.5 electrical conductivity (EC) salinity block to investigate their tolerance to salinity stress. Seven rice cultivars (Nonabokra, Basmati 2000, Kalomonok, Basmati 370, Basmati 385, Super Basmati, and Basmati 515 Tol-19) exhibited tolerance to salinity. Basmati 370 was tolerant to a high salinity level of 5.5 EC and showed high yield than other cultivars, however, Nonabokra outperformed other cultivars in terms of all yield attributes investigated in this study. These results were also verified via molecular screening of these genotypes by using already reported DNA markers. Polymorphic SSR marker (RM7075) associated with the SaltTOl QTL to evaluate the tolerance of rice varieties to salinity. This study showed that Nonabokra, Basmati 2000, Kalomonok, Basmati 370, Basmati 385, Super Basmati, and Basmati 515 Tol-19 performed better against salt stress and may be used as salinity-tolerant lines for future rice breeding programs.
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