Three insect growth regulators (IGR), the chitin synthesis inhibitors (CSI) teflubenzuron and hexaflumuron and the juvenile hormone mimic (JHM) pyriproxyfen, as well as the organophosphate (OP) pirimiphos-methyl, were evaluated for their activity against the cowpea weevil, Callosobruchus maculatus (F), in cowpea seeds stored for up to 8 months post-treatment. The initial activity data showed that, based on LC50 level, teflubenzuron had strong ovicidal activity (LC50 = 0.056 mg kg(-1)) followed by pirimiphos-methyl (1.82 mg kg(-1)) and pyriproxyfen (91.9 mg kg(-1)). The residual activity data showed that none of the IGRs tested had strong activity when applied at 200 mg kg(-1) in reducing the oviposition rates of C maculatus at various storage intervals up to 8 months post-treatment. However, teflubenzuron reduced adult emergence (F1 progeny), achieving control ranging from 96.2% at 1 month to 94.3% at 8 months. Hexaflumuron showed a similar trend in its residual activity, ranging between 93.8% control at 1 month to 88.2% control at 8 months post-treatment. However, pyriproxyfen was more active than the CSIs tested and caused complete suppression (100% control) of adult emergence at all storage intervals. Unlike the IGRs tested, pirimiphos-methyl applied at 25 mg kg(-1) was more effective in reducing oviposition rates of C maculatus up to 8 months post-treatment. A strong reduction of adult emergence was also observed at various bimonthly intervals (98.6% control at 1 month to 91.6% control at 8 months post-treatment). The persistence of hexaflumuron and pirimiphos-methyl in cowpea seeds was also studied over a period of 8 months. The loss of hexaflumuron residue in treated cowpeas (200 mg kg(-1)) was very slow during the first month post-treatment (4.43%). At the end of 8 months, the residue level had declined significantly to 46.4% of the initial applied rate. The loss of pirimiphos-methyl residue in treated cowpeas (25 mg kg(-1)) was relatively high during the first month post-treatment (36.7%) and increased to 81.6% after 8 months.

The present study was directed towards the habitat of various mite species as predators, fungivores or as parasites associated with insects inhabiting grains and stored products. Samples were collected monthly from maize, wheat flour, broad bean, wheat and rough rice in four governorates, Kafr El-Sheikh, Dakahleya, Gharbeya and Menoufeya during the period between March 2003 and February 2004. The results revealed that: 1) The mite survey revealed the occurrence of 13 predatory species belonging to one family of the suborder Gamasida, and 6 families of the suborder Actinedida. Also 7 species belong to 4 families of the suborder Acaridida, were recorded as scavengers or fungivores. 2) The most abundant predaceous mites were: Blattisocius keegani Fox followed by Cheyletus malaccensis Oudemans, then Blattisocius tarsalis (Berlese). 3) The most abundant fungivore mites were: Tyrophagus putrescentiae (Shranck), Rhizoglyphus robini Claparède, and Acarus siro Linnaeus. 4) The most infested stored grains with mites was maize followed by wheat, rough rice, broad bean seeds then wheat flour. 5) The major insect pests of stored grains and seeds and associated mites were listed herein.

Development of the rice moth, Corcyra cephalonica (Stainton), from first instar larvae to adults in a whole wheat flour medium, took 40.9 and 43.5 days for males and females, respectively. Adult longevity was 9.1 and 7.0 days for mated and virgin males; 8.3 and 8.0 days for mated and virgin females, respectively. Virgin females laid more eggs than mated ones and as the number of moths per cage increases, the number of eggs decrases. Maximum mating response occurred during the second night after emergence. The mean number of matings per female was 0.9. The mean number of matings per male was 3.2 while that for females was 1.2 at a sex ralio of 4♀:1 ♂. Multiple mating occurred among about 16 % of the females. All investigations were carried out, at 28 °C, 65 % relative humidity, and LD 14:10 h. Zusammenfassung Laboruntersuchungen zu Entwicklung, Überleben, Kopulation und Reproduktion der Reismotte, Corcyra cephalonica (Stainton) (Lep., Galleriidae) Die Entwicklung der Reismotte, C. cephalonica, dauerte von der Erstlarve bis zum Falter in Weizenmehl 40,9 bzw. 43,5 Tage für Männchen und Weibchen. Die Falter‐Lebensdauer betrug 9,1, und 7,0 Tage für kopulierte und nicht kopulierte Männchen bzw. 8,3 und 8,0 Tage für entsprechende Weibchen. Unbefruchtete Weibchen legten mehr Eier ab als befruchtete. Mit Zunahme der Falterzahl pro Käfig nahm die Zahl der Eier ab. Das Kopulationsmaximum zeigte sich während der 2. Nacht nach dem Schlüpfen. Die mittlere Zahl an Kopulationen pro Männchen betrug 3,2 und für Weibchen 1,2 bei einem Verhältnis von 4:1 zugunsten der Männchen. Mehrfachkopulation zeigten etwa 16 % der Weibchen. Alle Untersuchungen fanden bei 28,0 °C, 65 % rel. Luftfeuchte und 14:10 h Licht/Dunkelheit statt.

Laboratory and field studies were conducted to evaluate the effect of three inert dusts, diatomaceous earth, kaolin and katelsous as wheat grain protectants against some stored grain insects, i.e., Sitophilus oryzae, Rhizopertha domininca and Tribolium confusum. Inert dusts were mixed with wheat grain in the laboratory at different concentrations. Data obtained from the laboratory experiment showed that the LC50, s of diatomaceous earth, kaolin and katelsous were 0.234, 0.071 and 0.235% w/w, 6.033, 6.306 and 8.938% w/w and 0.495, 0.496 and 103.875% w/w against S. oryzae, R. dominica and T. confusum, respectively one day after treatment. Diatomaceous earth was more effective than the other tested materials where it achieved complete mortality for the three tested insects after two days of treatment at the rate of 0.5% w/w. Results also showed that kaolin and katelsous act slowly on the tested insects, where the higher rates of 8% w/w for kaolin and 0.4% w/w for katelsous gave complete mortality after one week post treatment. For the field study (at farmers , storages), the higher concentrations (0.5, 8 and 0.4% w/w) of the three dusts, diatomaceous earth, kaolin and katelsous, respectively obtained from laboratory experiment were admixed with wheat grain and stored for 4 months at the farms. For the field experiment, the results showed that diatomaceous earth gave 100%, 91.6% and 98.2% mortality against the three tested insects, respectively after 4 months of storage at a concentration of 0.5% w/w at 7 th day of exposure. Kaolin at 8% w/w showed that adult mortality decreased from 100% at zero time of storage after 5 days of exposure to 13.7%, 27.1% and 16.9 at 4 months of storage after the same period of exposure against the three tested insects respectively. At zero time of storage, katelsous at a rate of 0.4% w/w showed the percent mortalities of 100%, 100% and 95.7% against the three tested insects, respectively at 5 days of exposure. The residual effect after 4 months of storage decreased to 14.3%, 52.9% and 35.6% mortality against the three insects, respectively at the same time of exposure. In general the results obtained showed that the diatomaceous earth had the most activity followed by katelsous and kaolin against the three tested insects. Also, the degree of effectiveness decreased with the increasing of storage periods.