Resistance of tomato accessions from the horticulture germplasm bank to red spider mites: exploring mite preference patterns and antixenosis mechanism

Abstract

The red spider mite Tetranychus evansi can cause up to 90% yield losses to tomato crops. Mechanisms and causes of plant resistance to this pest could contribute to improved planning of plant breeding programs that prevent damage by this pest. It is known that the morphology and chemical compounds present in tomato plants are important to Tetranychus spp. success. This study aims at evaluating the resistance of 84 arbitrarily chosen tomato accessions obtained from the Horticulture Germplasm of the Universidade Federal de Viçosa (HGB-UFV), Minas Gerais State, Brazil to T. evansi. We evaluated the number of spider mites per leaf disk, number of trichomes/mm2, and the concentration of hydrocarbons of leaf disk. A significant difference in the number of T. evansi adults/leaf disk was found among accessions. The resistance mechanism of the HGB-UFV accessions was determined to be antixenosis. Accessions 2004, 2098, 2121, and 2100 had higher trichome density and the lowest adult T. evansi per tomato leaf disk. For this reason, these accessions should be chosen as sources of resistance in plant breeding programs. The hydrocarbons C 11 , C 13 , and C 22 had a negative correlation with T. evansi adults per leaf disk.