Twelve cultivares were grown along with released high yielding hybrid CSH-1 (susceptible to stem-borer) to investigate their relative resistance to stem-borer at three locations. Results obtained have established that the 12 cultivars possess moderate levels of resistance to stem-borer. The damage suffered by them was significantly lower than CSH-1. Further, four cultivars viz. E601, E 602, E 603 and E 604 suffered less damage.
The stability of the resistance was worked out by following the model of Eberhart and Russell (1966) [Crop Sci. 6, 36–40]. The means of various cultivars were calculated and regression coefficients (bi) were tested against unity to locate most adaptable cultivar for borer damage. The cultivar × environment interactions for leaf injury and stem tunnelling (two parameters used for assessing stem-borer damage) were significant and in most of the cases were due to linear response of different cultivars. Cultivar E 601 proved to be most promising and stable for resistance to stem-borer.
