Abstract

Faten Al-Fayed, Mariam al-Zawahiri, Mohamed Hosny, Demis Chahine

The black blister beetle Meloe proscarabaeus was firstly recorded in Egypt in (1976). It has attracted very little attention in spite of its status as an agricultural pest. The present study was conducted to investigate the food preference and consumption by adults of this beetle on four different host plants (viz., faba bean Vicia faba, Egyptian clover Trifolium alexandrinum, lettuce Lactuca sativa, and pea Pisum sativum) under laboratory conditions. Along a time interval of 12 h through 3 successive days, under the multiple-choice condition, two arenas of females and males were observed to determine the relative choice and preference % on each of the host plants. Relatively to V. faba, the feeding interest of adult females was estimated in 1.04 for T. alexandrinum, 2.26 for L. sativa, and 0.15 for P. sativum. These data indirectly indicate the highest consumption rate of female beetles on L. sativa and lowest rate on P. sativum. A similar trend of food preference was easily appreciated for male congeners. Under no-choice condition, the food intake, faeces output, and the relative consumption rate had been determined every day throughout the adult longevity. The mean food intake by adult females from V. faba was 1.35±0.39 mg/ ٍ . Comparatively, nonsignificantly smaller quantity from T. alexandrinum and the smallest ingested quantity from P. sativum were ingested. On the contrary, female adult beetles ingested considerably large amount of L. sativa. Generally, adult females discharged faeces comparable to the ingested food. For the male congeners, a similar feeding response could be recorded.