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The potato tuber moth (PTM) represents a dangerous pest on potato crop in Italy, spreading out from southern areas to central and northern areas. Introductions of Solanum berthaultii, S. commersonii, S. pinnatisectum, S. sparsipilum, S. spegazzini, S. sucurense, S. tarijense wild species and S. tuberosum × S. berthaultii hybrids were evaluated for resistance to a PTM population isolated from a field in central Italy, by means of an antibiosis test on tubers in the laboratory and of an antixenosis trial in the field. Several S. sparsipilum and S. pinnatisectum clones showed an antibiosis effect on larval survival and antixenosis of the aerial and the hypogeal parts of the plant. In the field, the genotypes with leaf glandular trichomes did not revcal the expected antixenosis effect of the acrial part of the plant. [ABSTRACT FROM AUTHOR]

Four introductions of Solanum berthaultii wild species and seven S. tuberosumxS. berthaultii hybrids were evaluated by antibiosis and antixenosis laboratory tests with potato tuber moth. Some morphological and chemical traits related to the trichomes were analysed. Two clones of the wild species S. sparsipilum and five of S. pinnatisectum, characterised by high tuber resistance, were tested for leaf resistance, both by antibiosis and antixenosis assays. The genotypes with high density of trichomes A and with high exudate PPO activity, showed a moderate negative effect on pupal weight and fecundity in the antibiosis tests. Trichomes B exudate showed a strong repulsive effect on oviposition of adult in the antixenosis tests. The S. pinnatisectum clones revealed a good leaf resistance level, whereas the S. sparsipilum clones showed lower levels of antibiosis and antixenosis. [ABSTRACT FROM AUTHOR]