Wheat cultivar susceptibility to grain damage by the New Zealand wheat bug, Nysius huttoni, and cultivar susceptibility to the effects of bug proteinase on baking quality.
Wheat infested with N. huttoni contains a salivary proteinase which results in a poor loaf volume and texture in the bread. Six New Zealand cultivars (Arawa, Batten, Domino, Karamu, Oroua and Otane) and 3 breeding lines (WW378, ASPS9927 and ASPS9928), selected to represent a variety of end uses, were grown in nylon mesh cages with and without N. huttoni at Lincoln, Canterbury, New Zealand in 1992-93 and 1993-94. For each season and cultivar, information is tabulated on wheat growth stage at colonization, visible damage and proteinase activity of flour. Significant genotypic differences were observed for reaction to N. huttoni damage, with Domino and Oroua showing less susceptibility to attack across both trials. High-quality genotypes such as Otane, Oroua, Domino and Batten were less susceptible to the effects of the salivary proteinase in baking than were poor-quality wheats. No relationship was observed between susceptibility to Nysius huttoni and grain or head characters.