Vol. 11, Issue 12 (2022)

Author(s):
Anju Mariam Joseph, Arya K, Veena Vighneswaran and Bindhya Mathew

Abstract:
Saltol, the major QTL for seedling stage salinity tolerance was mapped on chromosome 1 in an F₈ Recombinant Inbred Line (RIL) population obtained by a cross between a saline-tolerant landrace, Pokkali and salt-sensitive IR 29. The resultant genotype FL478 is used as a salinity tolerance donor. The present study screens various aspects of salinity stress response at various stress levels of two major saline-tolerant genotypes. The in vitro salinity screening revealed that FL478 is a better performer in comparison to Pokkali regarding salinity responses. The field salinity screening had a different result. At 6 dS m^-1, FL478 and Pokkali showed responses on par. As the stress levels increased, FL478 tends to suffer more stress injury and displays adaptation mechanisms deficit in comparison to Pokkali, especially in the reproductive stage. Saltol based tolerance may not be the only salinity response mechanism in Pokkali. The flowering stage response of the landrace may be indicative of other genes or QTLs in the Pokkali genome associated with reproductive stage salinity tolerance.