الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The present study was carried out to determine the effects of gamma radiation and plant extracts separately or combined on certain biological and histological aspects of the Black cut worm Agrotis ipsilon (Hufn ), throughout two successive generations.
This work comprised the study of effects of two low doses (75 and 150 Gy) of gamma irradiation as well as two species of plant extracts (M. azedarach and S. terebinthifolius). Special stress was given to study the reproductive biology and the histological changes in the gonads of the parental adult males, parental adult females and their Fi generation.
The obtained results could be summerized as follows:
1. Effect of Gamma Irradiation on Pi and Fi Generations:
1 When full grown male pupae were irradiated with the doses of 75 or 150, the number of deposited eggs per mated female was not significantly affected among Pi generations at the two tested radiation doses while it was significantly affected among F1 generation.
2 The egg hatchability percentage among PI and Ft generations was significantly reduced by increasing the radiation dose applied to PI male.
3.The two tested doses of gamma irradiation (75 and 150 Gy) did not clearly affect the percentage of mated females among Pi and F1 generations.
4.The- average number of spermatophore-s per mated female was not evidently different from the control.
5.Slight reduction in the percentage of inseminated females was observed at both doses among the two generations.
6.The percentage of total mortality of F1 larvae reaching adult
stage increased as the radiation dose applied to PI males increased.
7.The average developmental period from egg hatch to adult
emergence obviously increased in Fi progeny at the two tested irradiation doses.
8.The percentage of pupation was not affected at the tested
dose 75 Gy while a slight reduction in the pupation occurred at the dose 150 Gy.
9.There was an adverse relationship between the dose applied to the parental male and the adult emergence percent.
10.The percentage of malformed F1 adults increased greatly with the increase in the dose applied to parental generation.
11 The sex ratio among the progeny of irradiated males seemed to be about normal, where it was nearly 0.56 : 0.44 (male:female) at the two tested doses.
2. Effect of Plant Extracts on Pi and F1 Generations: A- Effect of petroleum ether (p.t.) extract treatment on certain biological aspects:
I. Petroleum ether (p.t) extract adversely affected total moitality in a concentration dependent mamiers.
2 Each of the (p.t) extract concentrations under investigation elongated larval duration, depending on concentration and species of plant dependant.
3.On contrast- with larvae (p.t) extracts caused non significant changes in pupal period at any of the tested concentration.
4.There was moderate gradient reduction in the pupation percentage of larvae survived after p.t extracts treatrnents compared to that resulted from the untreated larvae.
5.Percentages of adult emergence were inhibited by increasing the concentrations.
6.During adult emergence, different grades of deformities were noticed in a concentration dependent manner.
7.The previous results indicated that moderate fluctuations recorded by (p.t) extracts among sex ratio.
B- Effect of acetone extracts treatment on certain biological aspects:
1.Tabulated data revealed collinear relationship between the acetone (acet.) extracts concentrations and the total morality percentage. The highest percentage mortality occurred mainly with the M. azedarach extract.
2.Acetone extract treatments significantly elongated the develop-mental period which was plant species dependent. The highest elongation was recorded at the M. azedarach applied concentrations compared to moderate to mild elongation at S. terebinthifolius.
3.There was significant reduction in the pupation percentage compared to that resulted from the untreated larvae.
4.Recorded data exhibited slight reduction in the percentage of adult emergence from developed pupae resulted from
treated larvae because considerable larval death was occurred.
5.On the contrary, treating larvae with any of the two plant extracts under investigation showed significant increasing in the percentage of adult malformation.
6.Sex ratio was fluctuated within all tested concentrations.
C- Effect of plant extracts on reproductive biology through Pi generation:
1.The number of deposited eggs per mated female was obviously affected among the different mating combinations of plant extracts treatments. It was
significantly reduced at the combination of treated male with treated female.
2.It was observed that the eggs hatchability percentages
were significantly reduced at most mating combinations through both tested plants.
3.The reduction in mating ability percentage imcreased
almost gradually with the increase in the plant extracts
concentration. The highest effect occurred when both
treated males and females were crossed together.
4.The reduction in the average number of spermatophores per mated female was positively correlated with the concentration of plant extract. The greatest reduction occurred at Melia azedarach acetone extract when bo- th males and females were treated and crossed together.
5.The percentage of inseminated females decreased by increasing plant extract concentration applied to larvae and
reached its lowest value when both treated males and
females at M. azedarach extract were crossed together.