Effect of undersowing potatoes with grass on potato aphid numbers

The numbers of the potato aphids, Macrosiphum euphorbiae and Myzus persicae, were counted on potatoes undersown and not undersown with perennial ryegrass in field experiments during 1980 and 1981. The numbers of aphids on potatoes undersown with grass were found generally to be smaller than the aphid numbers on potatoes not undersown with grass. Tuber yields were not significantly reduced by the undersowing of potatoes. The agronomic feasibility of undersowing potatoes for aphid control is discussed.