الفهرس 
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Abstract
The present study was carried out to determine the effects of gamma radiation, Terminalia arjuna , Erythrina caffra, Taxodium distichum and Melaleuca cajuputi or their combination of Taxodium distichum and gamma radiation on certain biological and biochemical aspects of the cotton leaf worm, Spodoptera littoralis (Boisd.), throughout two successive generations.
The effects of three substerilizing doses of gamma radiation (100,150 and 300Gy) as well as five different concentrations of plant extracts (.625, 12.5, 2.5, 5and 10%) and the combined treatment of Taxodium with 100Gy was studied. Special attention was given to reproduction of the parental male adults and their F1 generation.
The obtained results could be summarized as follows:
1-Effect of gamma radiation on P1 and F1 generations :
1- The number of deposited eggs per mated female was not significantly affected among P1 and F1 generations at the low dose of radiation while it was significantly affected at the higher dose among P1 and F1 generations.
2- The egg hatch percentage among P1and F1 generations was significantly reduced by increasing the radiation dose applied to P1 male. The reduction of the percentage was higher among F1 generation.
3- The average number of spermatophores per mated P1 females was not evidently different from the control. While this number reduced significantly in F1 adult comparing with the control.
4- The three tested doses of gamma radiation (100, 150and 300Gy) did not clearly affect the percentage of mated females among P1 and F1 generations.
5- The percentage of F1 larvae survived to adult stage decreased as the radiation dose applied to P1 males was increased.
6- Irradiation of full grown male pupae with 100or 150Gy of gamma radiation did not significantly affect emerged adult longevity for males in P1 and for both males and females among F1 generation.
7- The average developmental period from egg hatch to adult emergence was slightly increased in F1 progeny at the low dose (100Gy ) and it was decreased at the high dose (150Gy).
8- The percentage of adult emergence was slightly reduced among F1generation at the two tested doses.
9- The reduction in F1 generation of was increased among F1generation at the two tested doses.
10- The growth index was inhibited with increasing the doses
11- The malformation percentage was higher in case of moths emerged from treated pupae at 150Gy than those in the treatment of 100Gy.
12- The sex ratio, among the progeny of irradiated P1 male slightly differed from the control (1:1).
13- The production of female adults resulting from P1 males irradiated with a dose level 100 or 150Gy and crossed with normal females was drastically decreased.
14- In general the deleterious effect of radiation was more pronounced in F1 generation.
2- Effect of substerilizing doses on the mating competitiveness of parent males
- Males irradiated by low doses of 100 and 150 were fully competitive.
- The comparison between means indicated that the 5:1:1and 3:1:1 (treated male: untreated male: untreated female) ratio consistently gave greater reduction in egg hatch than the 1:1:1 ratio among all tested doses.
3.Effect of Plant Extracts on P1 and F1 Generations:
A- Effect of petroleum ether (p.t.) extract treatment on certain biological aspects:
1-Petroleum ether (p.t) extract adversely affect total mortality in all plant concentration dependent manners.
2-Each of the (p.t) extract concentrations under investigation elongated larval duration, which were concentration and species of plant dependant.
3-On contrast with larvae (p.t) extracts caused a significant changes in pupal period at any of the tested concentration of plant dependant.
4-There was moderate gradient reduction in the pupation percent of larvae survived after p.t extracts treatments compared with that resulted from the untreated larvae .
5-Percentages of adult emergence were decreased by increasing the concentrations of four plants.
6-During adult emergence, different grades of deformities were noticed in concentration dependant manners.
7-The previous results indicated that moderate fluctuations recorded by (p.t) extracts among sex ratio.
8- The reduction in F1 progeny and growth was inhibited with increasing the concentrations as observed in four plant extracts compared to control
B- Effect of aqueous extracts treatment on certain biological aspects:
1- Data revealed the highest percentage mortality occurred mainly on the Termenalia extract.
2-Aqueous extract treatments significantly elongated the developmental period which was plant species dependent. The highest elongation was recorded at the Termenalia applied concentrations compared with moderate to mild elongation at three plants.
3-There was significant reduction in the pupation percent compared with that resulted from the untreated larvae .
4-Recorded data exhibited slight reduction in the percent of adult emergence from developed pupae resulted from treated larvae, because considerable larval death was occurred.
5-Sex ratio was fluctuated within the all tested concentrations.
6- The reduction in F1 progeny and growth was inhibited with increasing the concentrations as observed in four plant extracts compared to control.
C-Effects of chloroform extract treatment on certain biological aspects:
1-Tabulated data revealed collinear relationship between the chloroform extracts concentrations and the total morality percent. The highest percentage mortality occurred mainly on the Taxodium distichum extract.
2-Chloroform extract treatments significantly elongated the develop-mental period which was plant species dependent.
3-There was significant reduction in the pupation percent compared with that resulted from the untreated larvae .
4- Reduction in the percent of adult emergence.
5-Sex ratio was fluctuated within the all tested concentrations.
6- The reduction in F1 progeny and growth was inhibited with increasing the concentrations as observed in four plant extracts compared to control.
D- Effects of ethanol extract treatment on certain biological aspects:
1- The total morality percent was increased by increasing concentration . The highest percentage mortality occurred mainly on the Taxodium distichum and Terminalia extract.
2-Ethanol extract treatments significantly elongated the develop-mental period which was plant species dependent.
3-There was significant reduction in the pupation percent compared with that resulted from the untreated larvae .
4-Recorded data exhibited slight reduction in the percent of adult emergence from developed pupae resulted from treated larvae, because considerable larval death was occurred.
6-Sex ratio was fluctuated within the all tested concentrations.
7- The reduction in F1 progeny and growth was inhibited with increasing the concentrations as observed in four plant extracts compared to control.
3- Effect of plant extracts (Taxodium distichum) on reproductive biology:
A-Effect on F1 progeny resulting from treated P1 fourth instar larvae
1-The number of deposited eggs per mated female was obviously affected among the different mating combinations of plant extracts treatments. It was reduced significantly at the combination of treated male with treated female.
2-It was observed that the eggs hatchability percentages were significantly reduced at the most mating combinations through the both tested plants.
3-The reduction in mating ability percentage increased 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.
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 Taxodium distichum extract were crossed together.
6- The life span was decreased by increasing concentration of Taxodium distichum extract..
7-The production of female adults resulting from Taxodium distichum treated P1 males during the fourth instar larvae and crossed with untreated apposite one was decreased sharply by increasing the concentrations comparing with the control
B- Effect on F1 progeny resulting from treated P1 fourth instar larvae
1-The reduction in fecundity was significant at all concentrations compared with the control in both experiments (F1 treated male X untreated female and untreated male X F1 treated female).
2-The reduction in the percentage of egg hatch was negatively correlated with the Taxodium distichum extract given to P1 fourth instar larvae. The greatest reduction in egg–hatch occurred at 2,5,5 and 10 % in both experiments. .
3-The mating percentage did not clearly affect in F1 generation.
4-Generally, the average number of spermatophores per mated female was decreased by increasing concentrations.
5-Sex ratio of F1 progeny was around 1:1 to 3: 1.
6-The production of female adults resulting from Taxodium distichum extract treated P1 males during the fourth instar larvae and crossed with untreated apposite one was decreased sharply by increasing the concentrations comparing with the control.
III-The combined effect of Taxodium distichum extract and gamma radiation on F1 generation
Exposure of full grown male pupae to gamma irradiation (100Gy) following by treating F1 fourth instar larvae with Taxodium distichum (1.25 ethanol, 2.5% and water) extract was studied.
1-As general the number of deposited egg female was slightly affected.
2-The hatch percentage of eggs was sharply reduced in the treatment of 100Gy with Taxodium distichum (1.25 ethanol and 2.5% water) extract
3- The percentage of egg hatch inhibition was significantly increased by increasing the applied concentrations.
4- The combination of irradiation and Taxodium distichum (2.5% water and 12.5% ethanol) extract did not effect on the mating ability among F1 adults at the two tested treatments where it was almost similar to control.
5- The average number of spermatophores was reduced by increasing the doses of radiation and the concentrations of Taxodium distichum (2.5% water and 12.5 % ethanol) extract.
6- The percentage of F1 larvae survived to adult stage was reduced as the radiation dose and concentrations increased.
7- The sex ratio among F1 adults disturbed in the favour of males in all treatments.
8- The larval and pupal durations were relatively longer with the treatment of radiation with Taxodium distichum (2.5% water and 12.5% ethanol) extract.
9- The longevity of adults was decreased by increasing the doses of radiation and concentrations of Taxodium distichum (2.5% water and 12.5 % ethanol) extract.
10- The percentage of malformation among F1 adults was increased by increasing the doses of radiation and concentrations of Taxodium distichum (2.5% water and 12.5% ethanol) extract.
11- The developmental period from egg hatch to adult emergence was affected among F1 generation.
12- The greatest reduction in female production occurred when F1 males were crossed with untreated females.
13-The greatest reduction in F1 ¬generation and growth index occurred when F1 males were crossed with untreated females.
IIII – Chemical studied:-
A-Chemical investigation: -
The chemical investigation illustrate that Taxodium distichum , Terminalia arjuna , Melaleuca cajuput were rich in carbohydrate and Taxodium distichum was rich in flavonoids, flavonoid glcosides ,flavonols, Chalcones, tannins ,sterols and/or triterpenes and alkaloids or nitrogenous. Terminalia arjuna , Melaleuca cajuput were rich in flavonoids, ,flavonols, tannins ,sterols and/or triterpenes and alkaloids or nitrogenous. On the other hand, Terminalia arjuna was rich in saponins.
B-Biochemical effect of different treatments on free testosterone level , Cytochrome P450 reductase , Total Antioxidative Capacity (TAC) and Total oxidative Capacity(TOC) .
*The effect of radiation:
1-100 Gy elevated significantly of Total oxidative Capacity (TOC) in the male adult of P1 and F1 generation. On contrary, it reduced at Total Antioxidative Capacity (TAC)
2- The free testosterone level in P1and F1generation was decreased significantly at 100Gy treatment, this reduction also was indicated in F1 generation ,also, the cytochrome P450 reductase level in P1and F1generation was decreased significantly from control at 100Gy treatment.
** Effect of Taxodium distichum.
1- The free testosterone level P1 and F1 adults previously treated as F1 fourth instar larvae with the Taxodium distichum (2.5%ethanol or water extract) was significantly decreased from control. On the other hand the cytochrome P450 enzyme level in P1 and F1 adults also showed increased activity in all treatment.
2- The total antioxidation capacity (TAC) in P and F1generation was increased significantly .On contrary, the total oxidation capacity (TOC) in P1 and F1generation was decreased significantly.
***Effect of combined treatment of gamma radiation and Taxodium distichum .
1- The free testosterone level was significantly decreased by combined treatment at 100Gy and Taxodium distichum (1.25%ethanol or2.5% water extract) . The reduction in the hormone level was presented in both combination treatment .
2-The cytochrome P450 enzyme level was significantly increased by combined treatment of 100Gy and Taxodium distichum (12.5%ethanol or2.5% water extract )
3- The action of Taxodium distichum (12.5%ethanol or2.5% water extract)treatment on (TAC)level in P1 and F1 generation adults male previously treated as fourth instar larvae was increased significantly .On contrary the total oxidation capacity (TOC) in P1 and F1generation was decreased significantly.