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The number of annual generations and the life‐history of L. loreyi were studied under laboratory conditions. Seven complete generations and a partial eighth one could be reared successfully throughout about one year. The respective means of total duration of these generations were 38.2, 32.3 and 33.7 days for summer generations, 40.1 and 48.8 days for autumn generations, 92.0 days for winter generation and 70.4 and 49.5 days for spring generations. The durations of the different stages were negatively proportional to temperature. The egg, larval and pupal stages lasted for 3–13, 13–57 and 7–33 days, respectively. Under average laboratory temperature of 29° C and relative humidity of 70% larvae had six instars elapsing 2–4, 2–3, 2–3, 2, 2–3 and 4–6 days, respectively. Under the same conditions, the pre‐oviposition and oviposition periods were 1–5 and 2–4 days, respectively and the egglaying capacity of the mated female ranged between 327 and 939 eggs, with an average of 554.0 eggs. Zusammenfassung über die Biologie von Leucania loreyi Dup. Es wurden unter Laborbedingungen die Generationszahl und Lebensweise von L. loreyi untersucht. 7 vollständige Generationen und 1 partielle 8. konnten während eines Jahres gezogen werden. Die mittlere Dauer dieser Generation betrug 38,2, 32,3 und 33,7 Tage für die Sommergenerationen, 40,1 und 48,8 Tage für die Herbstgenerationen, 92,0 Tage für die Wintergeneration sowie 70,4 und 49,5 Tage für die Frühjahrsgeneration. Die Dauer der Entwicklungsstadien war der Temperatur umgekehrt proportioneil: sie betrug für das Ei 3–13, die Larven 13–57 und die Puppen 7–33 Tage. Bei einer mittleren Temperatur von 29° C und einer rel. Luftfeuchte von 70% entwickelten sich die Larvenstadien in 2–4 (L1), 2–3 (L2), 2–3 (L3), 2 (L4), 2–3 (L5) und 4–6 (L6) Tagen. Unter denselben Bedingungen wurden für die Präoviposition 1–5 und für die Oviposition 2–4 Tage beobachtet. Die mittlere Zahl abgelegter Eier betrug 554 (327–939).

Pilot field trials were conducted against Sesamia cretica Led. using a Granulosis Virus recently isolated from the corn borer infesting maize at Kafr El-Sheikh Governorate. The efficacy of spray application of ScGV was compared with the currently recommended chemical insecticides (Methomyl and Monocrotophos) as two different control strategies against S. cretica larvae on maize. The viral insecticide is a highly purified suspension of granules in water plus 10% molasses as a sticker as well as a feeding stimulant additive. The spray containing 0.1 g of granules/l (i.e. 1.48 x 10" I.B./ml) was applied twice at the rate of 1.25 and 2.5 l/O.Ol feddan (1 feddan = 4200 m' ) at 2 week intervals, starting 3 weeks after sowing. For the chemical insecticides, the methomyl was applied at the same time as the ScGV suspension against S. cretica larvae, and the monocrotophos was applice twice, 2 months after sowing, and 2 weeks later, against Ostrinia nubilalis and Chilo agamemnon larvae. All treatments were made using a portable knapsack sprayer. Additional plots were left as control. Results revealed that both tested treatments (microbial and chemical insecticides) noticeably reduced the numbers of S. cretica larvae. Regarding yield, the mean weight of seeds was higher for the plots which were treated with either virus or insecticide than untreated ones. However, the chemical insecticide treatment was more effective than the formulated virus treatment. The corrected yield in ardab (1 ardab = 145 kg)/feddan were 20.1 1, 16.04 and 12.79, for chemical insecticide, viral insecticide and control treatments, respectively. It is concluded that ScGV seems to be pathogenic to the field population of S. cretica and may be considered a promising biocontrol agent to support the Integrated Pest Management Programme of such an important corn borer.

No abstract

The foraging activity of the subterranean termite, Anacanthotermes ochraceus (Burmeister) (Isoptera: Hodotermitidae) was studied at El-Saidia village, Sennoures district, El-Fayoum Governorate, Egypt, throughout the two successive years 1997 and 1998 using perforated Polyvinyl chloride (P.V.C.) traps filled with corrugated cardboard paper then buried into the soil to a depth of 30 cm. Traps were replaced with new ones at monthly intervals. Parameters used for assessing foraging activity are % visited traps, number of workers, food consumption and soil translocation (construction activity).The percentage of visited traps ranged 0-34% in 1997 and 15-57 in 1998. The highest percentages of visited traps were recorded during July -October while relatively less percentages occurred between January and June. The vast majority of the foragers (98%) were workers but their numbers were not regarded as a reliable parameter for measuring foraging activity. Food consumption was relatively low during winter, more or less moderate during both spring and autumn and relatively high throughout summer with two distinct peaks; one in March -May and the other in September. Soil translocation increased progressively between January and September then tended to decline between October and December. Two peaks of soil translocation occurred; the first in May and the second in September. The relative efficiency of the four above-mentioned foraging activity parameters was discussed. Soil translocation seemed to be the most reliable quantitative parameter for the assessment of the foraging activity of the termite species under investigation.