Abstract
Sixteen varieties / advanced lines of cotton were tested at
Faisalabad for their relative resistance against insect pests
complex of cotton with reference to physico-ehemical factors,
like number of hairs on leaf uein and leaf lemina, length of
hair, number of gossypol glands on various plant parts, total
minerals, Ca, Fe, K, Mg, protein, fats and reducing sugars in .
the leaf tissue. Out of these varieties, AU-14 proved comparatively resistant to cotton Jassid whereas NL-ll~2-1, Stone
Ville 731-N and CIM-10 were very susceptable to it. The varieties did not reveal any significant difference among themselves with regard to whitefly and thrips populations. The
minimum number of cotton aphids / leaf was recorded on
Stone Ville 731-N whereas it was maximum on MNS-79.
Maximum attack of pink bollworm was on MNS-79 and
was minimum on NL-11-62-1, MNH-49, CIM-10 and A-89/
FM. Maximum number of hibernating larvae were found in
the seeds of NL-1l-62-1, whereas it was minimum in MNH93.
The spotted bollworm attack was minium on MNH-93
and maximum on CIM-10. AU-14 gave the highest yield.
Jassid was observed to be the key pest having negatiue correlation with yield.
