Transmission of beet yellows virus by alate and apterous aphids

Abstract

SUMMARY Myxus pusicae alatae and apterae were consistently better vectors than Aphis fabae of beet yellows virus, but there was little difference between the ability of alatae and apterae of each species to transmit.Alatae born and reared on infected plants transmitted no more readily than alatae that had fed on infected plants for only one day. No individual became infective after feeding on the plants for only 5 min., and few were infective after feeding for 30–60 min. Alatae and apterae were about equally infective after similar feeding times on infected plants.Apterae kept from feeding and at various temperatures up to 30°C. for 4 hr. after their infection feed, all transmitted equally often. Alatae transmitted as readily after a 4 hr. flight as after a 15 min. one. Some alatae of M. persicae remained infective longer than apterae, but most individuals of both ceased to be infective within 2 days of leaving infected plants. Most alatae ceased to fly 3–5 days after the final ecdysis because their flight muscles autolysed. A. fabae and Rhopalosiphoninus staphyleae transmitted BYV rather less than half as often as did M. persicae. Macrosiphum euphorbiae and Aulacorthum solani transmitted only rarely and transmissions were not obtained with Megoura viciae, Metopolophium festucae and Rhopalosiphoninus latysiphon.