Abstract

An experiment was conducted to evaluate the behaviour of the green peach aphid, Myzus persicae, on the foliage of 10 genotypes of hybrid potatoes (Solanum berthaultii × S. tuberosum), characterized by the presence of glandular trichomes A and B in their foliage. Two methodologies were used evaluate the resistance of the genotypes to the aphid: the first involved the use of intact plants and the second involved the use of excised leaves. Both methods were carried out under controlled temperature (20-25°C) and photoperiod (16:8). Data were recorded for aphid developmental time, survival, adult weight and fecundity. The relationship between the characteristic of the plant (densities of trichomes type A and B and the concentration of polyphenol oxidase [catechol oxidase]) and aphid behaviour was assessed. Aphid performance, in general, was affected by the hybrids, especially in the genotypes Q132-1, Q132016, Q132-22, P161-3 and P161-8. The methodology using excised leaves can be used to evaluate the resistance of hybrid potatoes to the aphids.