Resistance to Tetranychus evansi in Lycopersicon esculentum L. hirsutum var. glabratum hybrids

• Published in: The journal of horticultural science & biotechnology Vol. 84; no. 3; pp. 360 - 364
• Main Authors: Wosula, E. N., Knapp, M., Agong, S. G.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 01.01.2009
• ISSN: 1462-0316; 2380-4084
• DOI: 10.1080/14620316.2009.11512532

Cultivated tomato (Lycopersicon esculentum Mill. cv. Money Maker) was crossed with the spider mite-resistant wild tomato, Lycopersicon hirsutum var. glabratum Mull. accession 'LA 2204', and assessed for trichome density and resistance to the spider mite Tetranychus evansi Baker and Pritchard. Trichome types I, III, IV, V, VI, and VII were identified on the abaxial leaf surfaces of the parental genotypes, the inter-specific hybrid, and segregating F 2 ,BC 1 and BC 2 generations. Type IV trichomes were absent on 'Money Maker', while type V were absent on 'LA 2204', but the inter-specific hybrid and segregating generations possessed both type IV and type V.Type IV glandular trichomes were predominant on 'LA 2204'. Type V non-glandular trichomes were predominant on 'Money Maker'. No T. evansi larvae reached the adult stage on accession 'LA 2204'; while, on 'Money Maker', 52.5% of the larvae reached the adult stage. Mite fecundity and longevity were highest on 'Money Maker' (57.9 eggs/female; 13.1 d), and lowest on 'LA 2204' (0.04 eggs/female; 4.5 d), and intermediate on the inter-specific hybrid and all segregating generations. In repellence tests, with the thumbtack bioassay, the distance covered by mites on abaxial leaf surfaces was significantly higher on 'Money Maker' than on 'LA 2204', the inter-specific hybrid, or the segregating generations during the first 20 min. In choice tests, significantly more mites were attracted to 'Money Maker' than to the inter-specific hybrid and segregating generations.