Physiological variability of sorghum [sorghum bicolor (l.) Moench] under salt stress

Abstract

Sorghum is a major crop of the world, and its high economic value is due to its use of all plants parts for different purposes. It is moderately salt tolerant crop, more than maize and less than barley. Hence, its salt tolerance potential can be exploited for reclamation of saline soils. The study was conducted to evaluate the effect of salt stress on physiological maturity, affecting the economic yield of sorghum genotypes. To meet the objective, twenty one (SPH 1798, SPH1825, SPH 1858 (SS), SPH 1859, SPH 1860, SPH 1861, SPH 1862, SPV 2324, SPV 2456, SPV 2457, SPV 2458, SPV 2459, SPV 2460, SPV 2461, SPV 2462, CSH 22 SS (C), CSV 19 SS (C), CSV 24 SS (C), SSG 59-3, HJ-513 and HJ-541) sorghum genotypes were chosen and the crop was raised in plastic pots filled with dune sand saturated with two levels of salinity (8 and 10 dS/m) in screen house. Normal irrigated pots served as control. Physiological observation were recorded at different time intervals, but here the results obtained at physiological maturity viz. plant height, no. of leaves, total biomass, total dry weight and grain yield etc will be discussed. Overall, we found that 10 dS/m of salinity was more injurious to sorghum genotypes as only few could survive at this level and couldn’t yield significantly than 8 dS/m of salinity. At 8 dS/m of salinity, decreasing trend was observed for plant height, no. of leaves, total biomass, total dry weight and grain yield over control. The sorghum genotypes viz. SPH 1859, SPH 1861, SPV 2457, SPV 2461, SPV 2462 and HJ 541 survived and performed better up to physiological maturity stage at 8 dS/m of salinity level. Their better performance can be attributed due to more green leaf area (sq. cm/plant), total biomass (g) and total dry weight (g) at physiological maturity. Seed setting was observed in SPH 1859, SPH 1861, SPV 2457, SPV 2461, SPV 2462 and HJ 541sorghum genotypes at 8 dS m-1 of salinity. However, only two genotypes i.e. SPV 2457 and CSH 22SS (C) set seeds at 10 dS m-1 of salinity.