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Wheat, Triticum aestivum L. is an important cereal crops in Egypt. Corn leaf aphid, (Rhopalosiphum maidis Fitch) a species of aphid attacks plenty of the Gramineae plants and most cereal crops. The biological attributes of R. maidis reared on the nine wheat varieties, namely, Sids-12, Sids-14, Gimmiza-11, Giza-171, Misr-2, Bani suif-5, Bani suif-6, Suhag-4 and Suhag-5 were studied. The wheat varieties differed significantly in the duration of 1st, 2nd, 3rd and 4th nymphal instars. Wheat varieties effect significantly on the total developmental time of nymphal stage. The highest developmental time was recorded on Sids-14 variety with 5.80 days. On the other hand, data showed no significant differences between the nine wheat varieties in reproductive period. Bani suif-5 variety recorded the highest average number 11.90 days. On the other side, the aphids reared on Gimmiza-11 variety recorded the lowest average number 9.25 days. Data showed that the total number of offspring per female and mean number of offspring/day affected significantly by wheat varieties. There are a significant differences in longevity and generation period of R. miadis reared on the wheat varieties examined.

Effect of direct application of five bio- and conventional insecticides Dipel2x, Radiant, Proclaim, Aphox andCoragen) at three different concentrations on the biological attributes of immature (1st, 3rd and 5th nymphal instars) andadult stages of Orius albidipennis (Reuter) (Hemiptera: Anthocoridae) were evaluated. Procalim, Aphox and Coragenhad harmful effect and caused significant reduction in the tested stages of O. albidipennisas compared to Dipel 2x andRadiant insecticides, irrespective of tested concentrations. Also, the direct impact of those insecticides on immaturestages was higher than that recorded for adult stage. Insecticide-treated immature stages of O. albidipennis had negativeimpact on developmental periods. However, the longevity, fecundity rates and hatchability percentages of obtainedadults from insecticide-treated immature and insecticide- treated adult stages were differed from those of untreated(control).

Accordingly, this study was planned to investigate the effect of cold water and alcoholic extracts of Trigonellafoenum(fenugreek) and Lupinusluteus (yellow lupine) on the biological attributes and biochemical responses of the 4th instar larvae of Spodoptera littoralis (thecotton leafworm). The main objective of this study is to investigate the possibility of using plant extracts as insecticides to control the cotton leafworm. Thus, in our study a recommended pesticide namely chlorpyrifos (dursban) was used as a reference to compare its effect on some biological and biochemical aspects of the 4th instar larvae of the cotton leafwormwith those obtained from water and alcoholic extracts of fenugreek and yellow lupine. Results indicated that both water and alcoholic extracts of fenugreek and yellow lupine were effective against the cotton leafworm, especially at the concentration of 10%; while fenugreekextract was the most effective agent as it affects larval, pupal and adult stages of the tested insect. It also reduce protein level, alkaline and acid phosphatases levels. Thus we can conclude that extracts of fenugreek and yellow lupine can be used as a good insecticide against cotton leafworm.

Pulse grains in store suffer from great damage due to the attack of bruchid beetles, especially the pulse beetle(PB), Callosobruchus maculatus (Fabricius). The suitability of five common pulse species (chickpea, cowpea, fieldbean, pea and white bean) to infestation by C. maculatus was investigated. The effect of three legume species on thereproductive biology and adult longevity of PB, as well as the influence of different temperature regimes on itsdevelopment were also studied. Results indicated that the tested pulse species differed in their susceptibility toinfestation with PB. Cowpea seeds were the most susceptible, followed by chickpea and peas; however, white bean andfaba bean seeds showed high degree of tolerance even under heavy PB infestation. As for the effect of pulse species oncertain biological aspects of PB, the ovipositional period was the longest (17.13 days) for the adult females reared oncowpea, whereas the shortest (11.33 days) was recorded for those reared on chickpea. The mean number of eggs laid byPB female reared on cowpea (43.20 eggs) was higher than that laid by female reared on chickpea (35.00 eggs) and pea(32.20 eggs). The shortest longevity of adult males and females was recorded when reared on chickpea grains (14.67and 20.67 days, respectively), while the corresponding longest periods were 15.60 and 25.53 days on cowpea grains.Pertaining to the influence of temperature, PB did not complete its development at 40oC and above. Temperature had aprofound effect on the development of all immature stages of PB. The total developmental period of PB was negativelycorrelated to the increase of temperature; being longest (77.8 days) at the lowest tested temperature (20°C) and shortest(20.7 days) at 35°C. Longevity of either males or females also decreased as temperature increased.