Identification of an insect species causing bug damage in New Zealand wheats

Abstract

Abstract Insects of the species Nysius huttoni, Calocoris norvegicus , and Sidnia kinbergi were caged separately on plots of ‘Rongotea’ wheat at the watery ripe stage of grain development. S. kinbergi did not attack the grain in any detectable way. C. norvegicus attacked the grain producing pale circular marks on 40 – 45 grains per thousand. However, this attack did not result in any decrease in baking quality or proteolysis of gluten proteins as revealed by SDS‐P AGE. N. huttoni attacked the grain, producing 23 injured grains per thousand. This did not cause any reduction in baking quality, but SDS‐P AGE revealed proteolysis of gluten proteins consistent with that previously demonstrated for bug damaged commercial wheat lines. It is probable that this is the species of insect reponsible for bug damage in New Zealand.