الفهرس 
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Abstract
Laboratory experiments were carried out to study the efficacy of
bacterial commercial insecticides of Bacillus thuringiensis (Berliner)
namely Florbac, Bactospeine and Delfin on the different growth stages of
the pink bollworm, Pectinophora gossypiella (Saunders). The treated
stages included eggs, first and fourth larval instars and adults of P.
gossypiella. Each of these stages was treated with different concentrations
of the bioinsecticides and data were recorded from the tested and
subsequent stages and included mortalities, malformations, egg -laying
activity of the resulting adults and hatchability precentages amongst the
deposited eggs. Studies extended also to include the haemolymph of P.
gossypiella larvae, and inspections involved the total haemocyte counts
(THCs), differential haemocyte COlUltS(DHCs), haemolymph viscosity and
blood volume of treated and control larvae. The obtained results may be
summarized as follows:
I - Effect on different growth stages of P.gossypiella :
1.1. Eggs’ treatment:
The pink bollworm eggs were exposed to different concentrations of
each of the three bioinsecticides after about 24 and 72 hours of deposition.
I.1.A. Effect on hatchability :
The effect of eggs’ treatment after one and three days of deposition
with either of Florbac, Bactospeine or Delfin were, statistically,
insignificant (88 - 92, 86 -92 and 92% for eggs treated one and 3 days
after deposition and UIl1Ie*d eggs, respectively) .
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1.1. B. Effect on survival of hatched larvae:
Amongst the hatched larvae, significantly, higher mortality
percentages were recorded amongst those resulted from treated eggs than
control. More effect was, generally, detected amongst larvae that hatched
from eggs treated at 3 days than those treated at one day. The effect on
larval mortality appeared as a concentration dependent; i.e., increased by
the increase of the applied concentration.
I.I.e. Effect on pupal and adult mortality and malformations:
The percentages of successful pupation were negatively correlated
with the applied concentration. That was more evident amongst pupae
resulted from eggs treated after 3 days of deposition (95.65 -I 00, 91. 18 -
97.67 and 92 - 97.30/0 pupation by applying the maxima and minima
doses of Florbac, Bactospeine and Delfin, respectively). Moths emergence
was also affected due to eggs! treatment. Few larvae, pupae and adults
were found malformed.
1.1.D. Effect on larval period:
Treatment of 24 and 72 hours old eggs with either of Florbac,
Bactospeine and Delfin at different concentrations resulted in significant
prolongation in the duration of the hatched larvae than control (18.75 _
19.25, 18.51 - 18.79 and 18.37 -18.95 days, respectively, opposedto
15.77 days in case of the control larvae).
I.I.E. Effect on pupal period :
Significant prolongations in the pupal period were also detected due
to previous treatment with bioinsecticides at different concentrations (9.4 -
11.89, 9.62 -11.39 and 9.83 -11.64 days, respectively) than control (6.26
days).