Testing the susceptibility of kiwifruit (<i>Actinida chinensis</i> var. <i>deliciosa</i>) germplasm to <i>Hemiberlesia lataniae</i>

<p>This study demonstrates resistance in <i>Actinidia chinensis var. deliciosa</i> germplasm to the armoured scale insect <i>Hemiberlesia lataniae</i>, an important pest of kiwifruit in New Zealand. A bioassay was used to test the resistance of 120 vines from a germplasm collection in New Zealand. Fourteen of the vines were classified as resistant and five as moderately resistant. Eight crosses (two Susceptible (S) × Resistant (R); 1 R×S; 4 R×R; 1 S×S) were made from the original vines, and the resulting families examined for resistance. There were large differences in insect survival and size between the families. Three families from R×R parents and one from R×S parents had vines showing a hypersensitive-type response (plant cell death) to <i>H. lataniae</i>. There were large differences in the range of susceptibility to <i>H. lataniae</i> within families, suggesting that the trait is polygenic or that more than one resistance mechanism is present in the germplasm.</p>