Biology of the planthopper Sogatella vibix (Haupt) in Giza, Egypt (Hom., Delphacidae)

Abstract

Biology of the planthopper Sogatella vibix was studied on wheat seedlings in the glasshouse in Giza, Egypt. At 16–21 °C egg incubation period averaged 16.8 ± 0.09 days. At various temperatures incubation period range from 7–47 days. Total nymphal duration averaged 14.2–15 days at 22–30 °C, and 41.8–43 days at 11–20 °C, with no significant difference, in this respect, between the two sexes. At the former temperature, the five nymphal instars were completed in 3.0, 2.6, 2.8 and 3.7 days, respectively. Morphology and certain measurements of eggs and the five nymphal instars are given. At 11–18 °C pre-oviposition period of adult females was 32.3 days, adult longevity of males was 42.6 days and that of females was 58.1 days. At 14–23 °C, comparable durations were 15.3, 33.6 and 54.7 days, respectively. At the above two temperature-conditions, fecundity of adult females was 97.6 and 158.7 eggs/♀/life, respectively. Eight successive generations of Sogatella vibix were reared on wheat, in the glasshouse, from 11th of September 1973 to 1st of September 1974. The shortest generation occurred in August and lasted 27 days, and the longest occurred in January—March, lasting for 87 days.