Physiological Traits as the Primary Tool for Screening Salt Tolerance in Rice
K. Vanitha *
Department of Crop Physiology, TNAU, Coimbatore-641003, Tamil Nadu, India.
P. Shanthi
Department of Plant Breeding and Genetics, TNAU, Coimbatore 641003, India.
K. Subrahmaniyan
Tamil Nadu Rice Research Institute, Aduthurai 612101, India.
*Author to whom correspondence should be addressed.
Abstract
Salt stress is a common abiotic stress that significantly restricts crop development and productivity. Physiological alterations in response to salt stress were assessed for fourteen rice varieties during the panicle initiation stage at 120mM NaCl. Statistical analysis program (SPSS 15.0) was used to carry out the study. Under salt stress, all the rice varieties were assessed manifested a reduction in chlorophyll accumulation, stable chlorophylls, membranes and hydration status. On the other hand, all the varieties showed an increase in proline, hydrogen peroxide, and superoxide dismutase activity. It is noteworthy that the rice varieties surakuruvai, kaivarasamba, mallam punchai, and mappillai samba had better levels of salt tolerance than the salt-sensitive ones due to increased SOD activity, proline accumulation, relative water content, chlorophyll, and membrane stability index. The ability to tolerate salt during the reproductive stage under field conditions will be further investigated using these varieties.
Keywords: CSI proline, RWC, SOD, salt tolerance rice