Susceptibility of twenty potato cultivars to the potato moth at Pukekohe: a preliminary assessment.
Of 20 cultivars of potato tested in the field in New Zealand in 1973-74 for relative levels of foliar and tuber infestation by larvae of Phthorimaea operculella (Zell.), none showed any evidence of resistance, but varieties with a prolonged upright growth habit and few leaves close to the soil surface sustained low leaf-mining populations, and light tuber infestation was associated with growth habits such as deeper tuber set.<new para>ADDITIONAL ABSTRACT:<new para>Data are presented on the mean yields of 20 potato cultivars naturally infested by the tuber moth (Phthorimaea operculella). Total tuber yields varied from 2.9 kg/plot (10 plants) for cv. Red King Edward to 10.9 kg for Toru.<new para>ADDITIONAL ABSTRACT:<new para>In a field study, all 20 cultivars were infested with Phthorimaea operculella. Wha, Ono and 1584c10 were least seriously affected. Light tuber infestation was associated with upright growth habit and deep tuber set.