Physio-Biochemical Characterization of Sugarcane Genotypes for Waterlogging Tolerance

Waterlogging is one of the serious environmental constraints for optimum growth and yield of sugarcane. In India, waterlogging is caused due to excess monsoon rainfall, inadequate and improper drainage facilities. In present study, twenty four sugarcane genotypes including six commercial cultivars were tested under waterlogging and control conditions to determine leaf, stalk, root and whole clump dry weight, specific leaf weight, chlorophyll and carotenoids content for identifying waterlogging tolerant sugarcane genotypes based on tolerance indices. Current study clearly demonstrated that sugarcane plants growing under waterlogging conditions had significantly lower leaf, stalk and whole clump dry weight, specific leaf weight, leaf area, SPAD, chlorophyll a, b, total chlorophyll, carotenoids, P and K contents in leaf tissues. There was a great genotypic variation for all the investigated parameters. Under waterlogged condition stalk elongation rate was varied widely among different genotypes and it ranged between 0.016-0.909 cm/day. SR/AR ratio was found highest (5.59) in CoLk 07201 and lowest (0.795) in S 5087/11 genotype. Tolerance indices for stalk dry weight showed significant positive correlation with total clump dry weight, leaf weight, root weight, specific leaf weight, chlorophyll a, b, total chlorophyll and carotenoids. Sugarcane genotypes had different tolerance indices for the studied parameters; D-6-13, S 5090/11 and S 5085/11 had greater tolerance indices for stalk and whole clump dry weight and S5085/11, B-44-12 and CoS 767 for chlorophyll a, b total chlorophyll and carotenoids contents. Based on relative cane weight S 5085/11, CoLk 12206, LG 06605, LG 04439, UP 9530 and D-6-13 were identified the most waterlogging tolerant lines, while A-27-12 was found most susceptible. Abbreviations: SRshoot root; ARAerial root; P – Phosphorus; KPotassium; RGR Relative growth rate; SLWSpecific leaf weight; SPADSoil plant analysis development.