Different patterns of acid and alkaline phosphatases activities during embryogenesis and in emerged adults of Helicoverpa armigera (Lepidoptera: Noctuidae)

The acid phosphatase and alkaline phosphatase activities were studied in the developing eggs and in aging ovary and testis of pot-emerged adult of the cotton bollworm, Helicoverpa armigera at different time intervals from 0-72 hours. Acid phosphatase activity was higher than alkaline phosphatase and acts as cyclic during embryonic development. Alkaline phosphatase activity was slightly increased in the freshly laid eggs but decreased more sharply than acid phosphatase during embryonic development. In all groups of post-emerged adults, acid phosphatase activities were much greater than alkaline phosphatase at any given stage of progressively increasing age. Both enzymes were noticed to be cyclic in the post-emerged mated and non-mated adults. A conspicuous difference was noted between the activities of these enzymes in ovaries and testes of mated and non-mated adults. This phenomenon could be due to the periods of spermatozoa production in the testes and yolk accumulation in oocytes and ovulation. Mating could be also a factor that affected the phosphatases in both males and females.

Comparative studies of semi-artificial diets on the biology and the bionomics of the European corn borer, Ostrinia nubilalis Hübner (Or.: Lepidoptera, Fam. : Pyralidae)

Comparative studies of two semi-artificial diets (S.A.1 and S.A.2) as well as a natural corn diet were studied on the biology and bionomics of the European corn borer, Ostrinia nubilalis under laboratory conditions. The insect was successfully mass reared for ten successive generations at the conditions of 27 +/- 2 degrees C, 60-80% R.H. in addition of photoperiod of 6:18 (L: D) for larvae and 12:12 (L: D) for the other stages, respectively. Along ten successive generations, there were no significant differences between the larval periods for both artificial diets. The S.A.1 induced the shortest larval period (22.5 days) compared to the artificial diet S.A.2 (24 days) and the natural diet (25 days). Meanwhile, the rearing larvae on the natural diet revealed means of pre-pupal and pupal periods of 2 and 8 days which decreased to 2 and 6.5 days in both artificial diets (S.A.1 and S.A.2), respectively. However, the pupal weight and length were insignificantly increased in S.A.1 (121.7 g and 1.7 cm) than that in the natural diet (115.5 g and 1.8 cm) and were in the artificial diet S.A.2 (101.2 g and 1.7 cm), respectively. Moth longevity (pre-oviposition, oviposition and post-oviposition periods), was affected to a certain extent by the larval diets. The maximal moth longevity was recorded (15 days) for larva reared on the natural diets. On the other hand, the shortest period was observed (10.5 days) for the moth longevity in S.A.1. The artificial diet S.A.2 showed the moth longevity (13 days). The longest oviposition period was recorded (10 days) in the natural diet, while it was only (6.5 days) in the artificial diet S.A.1 compared with (8 days) in the artificial diet S.A.2. The number of the deposited eggs/female throughout the 10 successive generations was (400) in the natural diet, while the artificial diet S.A.1 revealed the least number (304.4) versus (358.2) in the artificial diet S.A.2. On the other hand, the number of hatched eggs/female were (320) in the natural diet, versus (310.9 and 256.5) in the artificial diet S.A.2 and S.A.1, consequently. The highest mean of hatchability percent was 86.93% resulted in the artificial diet S.A.2 compared to. 83.92% in the artificial diet S.A.1 and 80% in the natural diet. It was observed that the shortest total generation period found (41.5) days in the artificial diet S.A.1 while it was (50 and 45.5)days in the natural diet and the artificial diet S.A.2, consequently. The results declared that the artificial diet S.A.1 is a suitable artificial diet as it is considered mass rearing of the European corn borer, Ostrinia nubilalis Hub.

An approach for IPM program to control sucking pests infesting garden bean plants (Phaseolus vulgaris L.) in Egypt

An approach to eatablish IPM program for some sucking pests infesting garden beans plants was carried out in two successive seasons of 2004 and 2005 under field conditions in Alexandria, Egypt. The sucking pests included the aphid, Aphis craccivora Koch (Homoptera: Aphididae), the white fly, Bemisia tabaci Genn. (Homoptera: Aleyroidae) and the spider mite, Tetranychus urticae Koch Pymetrozine, thiamethoxam, carbosulfan, abamectin, azadirachtin and the detergent (Masrol 410) were tested for their efficacy in this study. Thiamethoxam, carbosulfan, and pymetrozine proved to be highly effective against Aphis craccivora Koch, while abamectin, azadirachtin, and the detergent (Masrol 410) provided a moderate effect. Moreover, thiamethoxam, pymetrozine, and abamectin showed remarkable efficacy against adults and immature stages of the whitefly, Bemisia tabaci. However, azadirachtin provided a moderate effect, while carbosulfan and detergent (Masrol 410) had no effect altogether on whiteflies. In addition, abamectin induced the highest toxicity effect against the red spider mite, Teteranychus urticae followed by azadirachtin and the detergent that provided moderate effects. IPM program could be achieved by using abamectin, pymetrozine and azadirachtin in a sequence pattern throughout the whole season. Furthermore, the performance of the used agrochemicals on certain nutritional elements of beans pods vr. Branco , i.e. nitrogen, phosphorus, potassium, iron, and magnesium were also studied with varied results.

Abamectin, pymetrozine and azadirachtin sequence as a unique solution to control the leafminer Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) infesting garden beans (Phaseolus vulgaris L.) in Egypt

Field trails were conducted to determine the performance of three different sequences as a unique solution for the control of the leaf miner Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) infesting garden beans (Phaseolus vulgaris L.) during the two successive seasons of 2004 and 2005. Furthermore, during the evaluation period, the side effect against the ectoparasite Diglyphus isaea (Walker) (Hymenoptera: Eulophidae) was put into consideration. Meanwhile, the comparative evaluation of the pesticides alone showed that abamectin and azadirachtin were highly effective against Liriomyza trifolii, while carbosulfan, pymetrozine and thiamethoxam provided to be of a moderate effect. Moreover, carbosulfan showed harmful effect to the larvae of the ectoparasite Diglyphus isaea (Walker), while abamectin and azadirachtin gave a moderate effect. Thiamethoxam and the the detergent (Masrol 410) had slight effect in this respect. The highly effective sequence among the sequences was abamectin, pymetrozine and azadirachtin, against Liriomyza trifolii (Burgess), with slight harmful effect on Diglyphus isaea (Walker). However the sequence of azadirachtin, pymetrozine and abamectin had a moderate effect on Liriomyza trifolii (Burgess) and exhibited a slight toxic effect on Diglyphus isaea (Walker). In contrast, the sequence of carbosulfan, thiamethoxam and pymetrozine was the least effective and represented a slight effect on Diglyphus isaea (Walker). From this study, it was concluded that abamectin, pymetrozine and azadirachtin sequence has proved to be a unique solution for the control of the leaf miner Liriomyza trifolii (Burgess) infesting garden beans (Phaseolus vulgaris L.) in Egypt.