SCREENING OF SIX RICE VARIETIES AGAINST YELLOW STEM BORER, Scirpophaga incertulus WALKER

Studies were conducted on the relative resistance of six rice varieties (Basmati-385, IRRI- 6, Basmati Super, Basmati- 370, DR- 83 and KSK- 282) against the yellow stem borer (Scirpophaga incertulus Walker) in 2007, at the Research Farm of Agricultural Faculty, Gomal University, Dera Ismail Khan. Maximum dead-hearts (58.35%) and white-ear heads (13.67%) were found in Basmati Super whereas minimum dead-hearts (13.63%) and white-ear heads (2.35%) were found in IRRI-6 followed by DR-83 and KSK-282 with 20.06% and 25.74% dead-hearts and 9.45% and 4.97% white ear heads, respectively. IRRI-6 was found not only tolerant to rice stem borer attack but also showed maximum number of tillers (49.60), spike length (32.61cm), grains spike^-1 (132.8), thousand grains weight (35.67g) and yield hectare^-1 (6.53 tons). However, it showed less plant height (97.22 cm) compared to other tested varieties. Over all, results showed that fine varieties (Basmati) were highly susceptible to the yellow stem borer compared to the coarse varieties tested.