Abstract

Totally 23 different rice cultivars were analyzed for pest attack and varying morphological studies from Chinsurah, West Bengal, India. The individual rice cultivars were planted in both shallow and semi-deep conditions, maintaining the two replicated yield trail (RYT) with randomized block design (RBD) pattern. It was observed that the dead heart (DH) disease caused by Scirpophaga incertulas affects mostly NDR 8027 rice cultivar, which had maximum tillers in both shallow and semi deep conditions. The OR 2329-2 was less affected by DH, having minimum tillers in both shallow and semi deep conditions. The dead heart damages were directly proportional to the tillering stage and reproductive stage of rice plant. The mean value of pest attack in semi-deep land situation (SDW) (6.62%) was lesser than the mean value of pest attack in a shallow land situation (SHW) (6.68%). When compared the plant height of all 23 rice cultivars in shallow land was shorter than semi-deep land. From statistical analysis, it was understood that the rice cultivars of semi-deep land areas are less affected by insect-pest damage than the rice varieties of the shallow land area during the Kharif season. The rice cultivars grown in semi-deep land with high water depth were less damaged by pest and the plant heights of semi-deep land area is higher than the plants of the shallow land area. From this study, we concluded that the rice cultivation in semi-deep land condition is more beneficial than shallow land condition.

Key words: Rice cultivar, Scirpophaga incertulas, plant morphology, Kharif season, insect-pest damage.