Effect of sequential programs, insecticides alternatives against cotton boll worms and it\'s side effects on the quantity and quality of cotton crop middle Egypt

06-07-2017 15:25

The effect of sequence control sprays on cotton bollworms P. gossypiella and spiny bollworn, E. insulana on the average percent of infestation, the % reduction of bollworms population, economic losses in cotton yields and average of actual yield.
The 3 program was the most effective one against cotton bollworms, the seasonal percentages of reduction for spiny and pink bollworms were 92.85 and 94.86 % as compared with the Recommended Ministry Program (RMP), (87.65 and 81.67 % for both insects, respectively).
The 1st' 2 and 3rd programs didn't affect significantly on the total common predators in cotton fields while the 4th and 5th programs didn't affected significant on the total common predators as compared with the untreated check, while ministry program effect highly significant on the total common predators on the cotton fields, showing the average percentage of reduction was 65.0%.
The % economic losses in cotton yields and average actual yield were 4.76 % and 8.45 kentar / fed. as compared with the (RMP), (5.95 % and 8.55 kentar I fed.) , respectively. The seasonal percentage of reduction for pink and spiny bollworms were 86.62, 82.22 , 80.19, 83.90 % and 86.67,79.44, 79.44, 70.42 % for the 1st, 2nd, 4th and 5th programs applied to control both insects as compared with the Ministry program (87.65 and 81.67 %), respectively. The % economic losses in cotton yields and average actual yield were (5.37, 7.89, 10.32, 8.35 %) and 8.1, 8.05, 7.14, 7.95) kentar / fed. for the 1st, 2nd, 4th and 5th programs applied to control both insects as compared with the ministry program
(5.95% and 8.55 kentar / fed.) respectively.
Concerning the effect of these programs on the chemical properties, oil and protein , it proved no effect .The difference in fiber length at 2.5 % SL affected by these programs. The differences in fiber length (Pressley index) did not affected by these program. The highest value of micronaire reading (4.53 micronaire unit) resulted from 5th program as a
compared with the Ministry Program (4.37 miconaire unit).