Host plant selection by the wheat bug <i>Nysius huttoni</i> (Hemiptera: Lygaeidae) on a range of potential trap plant species

Abstract

Nysius huttoni is an endemic New Zealand insect pest. Its feeding can seriously reduce crop establishment in forage brassicas. A series of choice, no-choice and paired-choice tests were conducted in a controlled- temperature room to evaluate the pest’s host preferences on seedlings of eight plant species: Lobularia maritima (alyssum), Triticum aestivum (wheat), Phacelia tanacetifolia (phacelia), Fagopyrum esculentum (buckwheat), Coriandrum sativum (coriander), Trifolium repens (white clover) and Medicago sativa (alfalfa), and Brassica oleracea (kale) as a potentially susceptible control. In choice tests, wheat was the most preferred followed by alyssum, buckwheat and phacelia, all being signi cantly more favoured than kale. Survival rate of wheat bugs over 120 h was: on phacelia (71.0%), clover (69.0%), alyssum (48.0%) and wheat (47%), which were all signi cantly higher than on kale seedlings. Alyssum and wheat were more susceptible to N. huttoni feeding damage than were other tested plants. High survival rates were recorded in paired choice tests on kale and alyssum (78.3%) compared with the other paired choice tests. The implications of these ndings are important for developing ecological management strategies in, or around, forage brassica elds.