An assessment of insidious pest damage to 26 varieties of seven species of herbage legumes

Abstract

During 1977–79 the dry-matter yield of 26 herbage legume varieties receiving frequent applications of the organophosphorous pesticide phorate was compared with that of untreated plots. The total annual DM yield of sainfoin and lucerne was not affected by pesticide treatment. White clover yield was affected: pesticide application increased the DM production of the nine varieties studied by, on average, 9% in 1978 and 13% in 1979. The proportion of white clover present in white clover/ryegrass plots was enhanced by pesticide treatment. No attempt was made to establish the identity of the pest group(s) that may have been responsible for these effects. In a second experiment there was no significant effect on seedling establishment from phorate treatment applied to six legume varieties at the time of sowing.