Bollworm, Earias fabia Stoll, were reared in laboratory of resistance studies. For their rearing suitability, Okra leaves and fruits were compared with cotton. Okra leaves and fruits were found suitable for oviposition site and Eariase fabia diet, as good as cotton leaves respectively, at 95% confidence limits. Comparative egg incubation period, larval period, pupal period and preoviposition period have been determined. Okra leave and fruits showed no adverse effect on total life period of the Earias fabia as compared to cotton.
Resistance against monocrotophos and cypermethrin has been studied as compared to the neem product, LD50 values were found out with contact method. Thereafter, various resistant and susceptible strains were developed and designated as kar (Karachi, susceptible strain), mem. (memo goth strain), SA(Sindh A strain), SB (Sindh B strain) from sindh and kab (kabirwalah strain), Mult. (Multan strain) DG (D.G Khan strain ) from Punjab. LD50 values at post 24 hours cypermethrin treatment were found as 0.00657 (0.0061-0.0071) microgram per larva against kar, 0.1919 microgram per larva (0.0769-0.479) against , 0.1508 S.A 0.1508 microgram per larva (0.05997-0.37918) against mem, 0.2328 (0.1773-0.3056) microgram per larva against SB, 0.3613 (0.2405-05427) against kab, 0.3818 (0.22634-0.5533) against Mult and 0.33407 (0.223-0.4789) microgram per larva against DG strain upon probit analysis, LD50 values of Monocrotophos at 24hours post-treatment over found to be 0.94997 (0.742-1.215) against kar, 20.742 (15.383-27.967) against mem, 24.391 (15.943-37.317 ) against SA, 28.50 (194.08-418.51) against SB, 36.729 (21.833-61.789) against kab, 44.528 (33.705-58.825) against Mult strain and 40.282 (29.8246-54.407) microgram per larva against DG strain respectively. LD50 values of neem product were determined as 4.39(3.173-6.079) microliter per larva against kar, 4.35(3.232-5.874) microliter per larva against Mem, 5.49(3.963-7.607) microliter per larva against SA, 6.03(5.169-7.035) microliter per larva against SB, 5.526 (4.539-5.726) microliter per larva against kab, 6.455(5.061-8.233) microliter per larva against Mult and 5.097 (4.314-6.022) microliter per larva against DG strain.
The resistance ratio was determined as 23.0, 29.21, 18.104.22.168, 58.1 and 49.787 for mem, SA, SB, kab, Mult and DG strains, respectively against cypermethrin and 21.84, 25.68, 30.0, 38.676, 46.89 and 42.42 for mem, SA, SB, Kab, Mult and DG strains, respectively against monocrotophos. Whereas this ratio was fond to be 0.991, 1.25,1.37, 1.26, 1.47, and 1.16 against neem product respectively.
Estimation of various enzymes and protein content has been carried out in treated insects and compared with untreated larva of the respective strain. It was observed that in cypermethrin treated insects a total reductions in protein content was found to be 34.57%, 37.0% , 35.741% , 36.0%, 35.71% , 31.3%, 33.33%, in kar, mem, SA, SB kab mult and DG stains respectively. An increased was found in kar, Mem, SA, SB, Kab, Mult and DG strain respectively. In the case of neem oil, results shows that this compound caused an average reductions in protein contents of the insect under its effects. An average reduction of 49.0% 46.% 46.43%, 44.55% 41.83, 40.0% and 42.7% was observed in Kar, mem, SA, SB, kab, Mult and DG strains respectively.
An average inhibition of 39.0%, 40.0% , 43.0% 44.94%, 47.49%, 50.94 and 46.0% of the total esterases was estimated in cypermethrin treated insect and 45.0%, 46.0%, 48.5% , 49.0% 52.0% , 53.0% and 49.5% inhibition in monocrotophos treated insect was estimated in kar, mem, SA, SB, kab, Mult and DG strains respectively. Whereas in neem treated insects an average inhibitions of 50.85, 52.0%, 51.1%, 52.6%, 52.0%, 56.0% , and 54.0% of the total esterases was determined in Kar mem, SA, SB kar, mem, SA, SB, kab, Mult and DG strain respectively.
An average inhibition I alkaline phosphastase was ensured as 38.9%, 43.5%, 35.0%, 39.0%, 38.0%, 38.0% and 40.0% under the effects of cypermethrin, while under the effects of monocrotophos 46.0%, 51.0%, 63.9%, 67.0%, 62.0%, 59.0% and 60.0% inhibition was observed, whereas neem product caused an average inhibition of 42.0%, 44.0%, 36.0%, 40.0%, 39.0%, 42.0% and 41.0% in kar, mem, SA, SB, kab, Mult and DG strains, respectively.
The acetyl-cholinesterase was found inhibited to be 29.0% in kar, 37.0% in mem, 37.0% in SA. 34.0% in SB 30.0% in kab, 27.0% in Mult, 28.0% in DG strain due to cypermethrin treatment. Under the affect of monocrotophos the acetyl cholinesterase inhibition was estimated as 74.4 in kar, 65.0% in mem, 61.1% _ in Sa, 64.0% in SB, 17.86% in kab, 29.0% in Mult, and 41.3% in DG strain. Whereas the neem product caused an average inhibition of acetylcholinestrase 38.5% in kar, 44.0% in mem, 61.0% in Sa, 59.0% in SA, 36.0% in kab, 41.0% in Mult and 40.0% DG strain.
Quantitative measurement of pesticides in treated larvae was made by employing chromatographic techniques. Gas chromatography was used for the determination of synthetic compound in treated larva. HPLC technique was used for the determination neemproduct in treated larvae. Gas chromatographic analysis results show that both synthetic compounds were undetectable with technique in treated larvae. It has been observed that there was no significant difference in the amount of neemproduct, recovered from various insecticide resistant and susceptible strains