Variation in drought tolerance, its anatomical basis and inheritance in lowland rice

摘要

Variation in drought tolerance was studied in 25 rice genotypes based on artificial drought treatment of 21-day-old seedlings. Varieties Swarna, IR36, CR1006 and Rahaspanjar were tolerant. These had a higher number of roots per seedling. Recovery score of Swarna, IR36 and CR1006 was better than that of the control variety N22. Microscopic studies showed intact air sacs in tolerant genotypes which were deformed in the susceptible control. Segregation ratios in F2 hybrids of 4 crosses revealed that at least 2 genes are responsible for expression of drought tolerance.