PESTS AND PLANT INJURY ON LUPINS IN THE SOUTH OF ENGLAND

Pests were monitored on plots of Lupinus albus and other Lupinus speci es in Hertfordshire and Bedfordshire between 1986 and 1990. Slug damag e was common in winter on autumn-sown plants. Sitona lineatus (Curculi onidae) caused some feeding damage but larvae were not found. Delia pl atura (Anthomyidae) larvae severely damaged shoots and hypocotyls of l ate spring-sown.L. albus plants in 1986 and probably injured autumn-so wn seedlings. In autumn-sown L. albus following a barley (Hordeum sp.) crop, Thrips angusticeps seriously injured leaves and flower buds in April and May. The aphid Macrosiphum albifrons was present each year a nd probably overwintered on autumn-sown L. albus in 1989/1990. Its dis tribution was patchy and injury was most severe in flowering plants. M . albifrons is a vector for bean yellow mosaic virus which was found i n L. albus in Norfolk. Twelve other aphid species were found on lupin, five forming colonies; Aphis craccivora and Macrosiphum euphorbiae we re the most abundant. Damage by lepidopteran larvae was slight; the to rtricids Cnephasia asseclana and C. pasiuana were most common. Mirids, cicadellids and leaf miners caused negligible injury. Pollen beetles (Meligethes spp.) were found in flowers and mature flower buds. No sig nificant beneficial effects of combined insecticide and fungicide trea tments were measured. Macrosiphum albifrons, slugs, T. angusticeps and D. platura probably have the greatest pest potential.