ABSTRACT
Three synthetic compounds namely: A = 3-amino-5-chloro-4- phenyl azo-1H-pyrazole, B = 3-amino-5-mercapto-4- phenyl azo-1H-pyrazole, C = 3-amino-5- hydrazino-4-phenylazo-1H-pyrazole were tested on neonate larvae of Spiny bollworm, Earias insulana (Boisd.) at constant conditions of 27±2ºC and 65±4% R.H. Acute toxicity as well as their latent effects on the different stages of the survived larvae were studied.
Corresponding to the acute toxicity, at LC50 level the toxicity effect of the four tested chemicals were in descending order as follows: A, C, and B compounds. During larval stage, phenyl pyrazoles caused insignificant prolongation in duration of the larval stage of spiny bollworm. All tested chemicals showed highly significant decreased in the larval weight of spiny bollworm. All compounds caused insignificant increases on larval mortality percentage of spiny bollworm compared with control.
78All tested chemicals resulted in pupation percentages less than control. Pupal weights were not affected significantly with the tested chemicals. All compounds caused insignificant decreases on pupal durations of spiny bollworm compared with control. Significant differences were found between the tested compounds and untreated check on pupal mortality.
Percent of adult’s emergence was significantly affected by the tested compounds. The sex ratio of emerged adult’s spiny bollworm was insignificantly affected by the three tested compounds compared with untreated ones. A, B, and C compounds shortened the male longevity compared with the untreated. A and B compounds shortened the female longevity compared with untreated. But C compound elongated the female longevity compared with the untreated check.
All treatments decreased number of deposited eggs, which proved significant with A, B, and C chemicals. Incubation periods did not affect. Significantly B, A, and C compounds caused reduction in the hatchability of deposited eggs by spiny bollworm female survived from treated newly hatched larvae.
