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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 *

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The functional response of the parasitoid Dinarmus basalis (Rond.) (Hymenoptera: Pteromalidae) is determined to evaluate its potential as a biological control agent. Four female wasps in the presence of males parasitoids, were allowed to oviposit during their life span or hosts at different densities. The data were fit by Rogers′ (1972) parasitoid model. The rate of parasitoid search was a′= 0.123 ±0.005 life span -1 , and handling time Th = 0.056 ± 0.002 life span -1 . Volume of grain had no significant (P>0.001) effect on number of parasitoids emerging.

Antifungal activity of the D. indica (Lam.) Bennet. extractives collected in CHCl 3 and methanol were tested against seven pathogenic fungi F. vasinfectum, A. fumigatus, A. niger, A. flavus, Mucor sp., C. albicans and P. notatum at concentrations of 50 and 200 µg/disc along with a standard Nystatin (50 µg/disc). The fruit shell extract showed activity index against C. albicans and P. notatum. The leaf and the root bark extracts were responsive on A. fumigatus, C. albicans, P. notatum and F. vasinfectum

Context: Sythetic pyrethroid and two botanical may reduce the fecundity and egg viability of red flour beetle, Tribolium castaneum (Herbst) and can be used in grain protection. Objective:To determine the effect of cypermethrin, fenitrothion, Murraya paniculata L. and Jatropha gossypifolia L. plant extracts on fecundity and egg viability of T castaneum. Materials and Methods:Newly hatched T. castaneum larvae were kept in a petridish containing 30 g either fresh or treated flour separately. After pupation the pupae were sieved and sexed by microscopic examination and kept separately for adult emergence. Twenty five pairs (1♂: 1♀) adults were paired from treated and one pair from untreated media and placed in a glass vial containing 2 g of food either treated or untreated for oviposition in an incubator at 30 ± 0.5°C. Eggs were collected and counted after every three days over a period of 45 days. The eggs laid by the first 15 pairs from each treatment were collected from the experimental vials and kept in separate petridish for hatching. Eggs were regularly observed with a microscope and hatched larvae were counted. Results:The females of all treated media laid less number of eggs than the untreated females. Both insecticides and botanicals affected oviposition significantly (P<0.001) at all doses levels. All the treatments of both the insecticides and botanicals significantly (P < 0.001) reduced the fertility of eggs laid by T. castaneum females in comparison to those of the control. Conclusion:The plant extracts of kamini and jamalgota can effectively reduced the fecundity and egg viability against stored product insect pests with low mamalian toxicity

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Fecundity and egg viability of Tribolium castaneum (Herbst) females were significantly (P<0.01) reduced by synthetic pyrethroids and an alkaloid containing insecticide nimbicidine. In control, the average number of eggs laid by each female/day was 12.18. The lowest number of eggs laid by each female/day was noted as 4.38 when combining nimbicidine with two pyrethroids i.e., cypermethrin and deltamethrin. The percentage of egg hatching without insecticide treatment was 95%. The lowest percent of egg hatching was 63.95 when the adult female was fed on flour medium treated with combined doses of cypermethrin, deltamethrin and nimbicidine. Among the treated insecticides, nimbicidine (80.69%) proved effective in reducing the fertility than those of cypermethrin (86.05%) and deltamethrin (88.52%).