Studies on tolerance level of advanced cotton strains to insects pest complex

Abstract

An experiment was conducted to assess the relative resistance of different advance cotton strains viz. CRIS-129, CRIS-477, CRIS-486 along with a commercial check variety, CRIS-134 against sucking insect pests, i.e., thrips, jassids, whitefly and Bollworms under unsprayed condition during 2008 and 2009. The results revealed that maximum pest population of sucking insect pests and bollworm damage was found on advance strain CRIS-129 followed by CRIS-477, CRIS-486 and CRIS-134, whereas, lowest seed cotton yield 1734-ha kg per hectare was obtained from CRIS-486 while highest (2332-ha) from CRIS-134. However, advance strains CRIS- 477, CRIS-486 and commercial variety   CRIS-134 were remained moderate in degree of resistance against cotton insect pest complex during 2008. Similarly, during 2009 maximum pest population of sucking pests and bollworm damage was recorded on CRIS-129 followed by CRIS-486 and CRIS-134 and CRIS-477. The maximum seed cotton yield was also recorded in CRIS-134  (1944 kg-ha) followed by CRIS-477 (1853 kg-ha),CRIS-486 (1734 kg-ha) and CRIS-129 (1614 kg-ha).