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Life table of Tetranychus urticae and Phytoseiulus persimilis on bean leaflets were studied under laboratory conditions in three seasons. For T. urticae the development time from egg to adult varied from 7 to 24 days and the highest immature mortality was 78.70 % in winter. Eggs laid by females were 88.1 eggs in autumn and 70.6 eggs in summer season. The gross reproductive rate (GRR) was the highest (65.51) in autumn and 52.50 in summer. The net reproductive rate (Ro) was the highest (

Context: Medicinal plants contains some pesticidal activities that may control stored product insects.Objectives: To elucidate the insecticidal activity from the stem bark extracts of nishinda (Vitex negundo L.) and their toxicity against red flour beetle, Tribolium castaneum (Herbst) (Tenebrionidae). Materials and Methods:The powdered stem bark (250 g) was extracted with methanol (MeOH), ethyl acetate (EtOAc), acetone and chloroform sequentially. Solvents were evaporated using a rotary evaporator to obtained dry extract, weighed and re-dissolved in the same solvent from which they were extracted for bioassay. Red flour beetles were reared for the experiment in 500 ml beakers containing food medium and kept in a control temperature room (30 ± 0.5 0 C). Residual film bioassay was used to evaluate the toxicity. The adult mortality of T. castaneum (CTC-12, FSS-II and KANO strains) was recorded after 24, 48 and 72 h, but for larvae, the mortality was recorded on 12 th and 20 th larval day after treatment. The mortality percentages were subjected to probit analysis. Results:The LD50 values for first through fourth instar larvae were more or less similar whereas, LD50 for fifth instar larva and adults were the lowest. Among the solvents, methanolic extracts elucidated more toxicity on both adult and larval insects. The degree of toxicity of the extracts according to solvents was MeOH>Pet spt.>acetone>EtOAc. The susceptibility order according to insect strains was FSS-II>CTC-12>KANO. Conclusion:The results suggest the presence of active toxic substances of nishinda acting after consumption or topical application on T. castaneum. Methanolic extracts of the plant provided the most potent and reliable control of the flour beetle.

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The parasitic wasp Anisopteromalus calandrae (Howard) was released at six (5, 10, 20, 30, 40 and 50 pairs) densities to evaluate the effects of different introduction rates in controlling residual populations of the lesser grain borer Rhyzopertha dominica (Fabricius) in wheat grain stored in bulk in 46 m 2 rooms. At the 50-pair density, the parasitoid suppressed 83% of R. dominica in June -July and 74% in August -September. At the 5-pair density, the numbers of F 1 progeny per female were 44 and 51, during the first and second period, respectively while at the 50-pair release rate, only 6 and 7 individuals were recorded, respectively. In a second test, the effects of different materials used for storing were evaluated on both insects. Five hundred (500) grain-residing 20 -22-day-old R. dominica larvae were mixed with 250 g fresh wheat stored separately in each of five types of bags, i.e. jute, calico (Americana cloth), polypropylene, polythene, nylon, then exposed to 50 pairs of A. calandrae. The parasitoid suppressed host populations in all types of bags, except in those made of polythene. The highest percentage (69 and 81%) suppression occurred in calico bags during the June -July and August-September periods, respectively. The lowest suppression of 51 and 57% was observed for polypropylene bags during the respective periods. The parasitoid-induced mortality was positively correlated with the parasitoid density.Résumé. L'influence du nombre de guêpes parasitoïdes Anisopteromalus calandrae (Howard) ((5, 10, 20, 30, 40 et 50 couples) sur la suppression des populations résiduelles du petit bostryches des grains Rhyzopertha dominica (Fabricius) a été étudiée dans des greniers à blé de 46 m 2 . A la densité de 50 couples, le parasitoïde élimine 83% des bostryches en juin-juillet et 74% en aoû t-septembre. A la densité de 5 couples, le nombre de descendants F1/femelle est de 44 et 51 au cours de la première et de la seconde période respectivement alors qu'à la densité de 50 couples, on a dénombré respectivement 6 et 7 *