Biology Articles » Anatomy & Physiology » Anatomy, Plant » Effect of allelochemicals in tomato leaf trichomes on mite (Tetranychus urticae Koch.) repellency in genotypes with different levels of 2-tridecanone

Effect of allelochemicals in tomato leaf trichomes on mite (Tetranychus urticae Koch.) repellency in genotypes with different levels of 2-tridecanone

ARAGAO, Carlos Alberto, DANTAS, Bárbara França and BENITES, Flávio Rodrigo Gandolfi

Abstract : For the evaluation of the mites (Tetranychus urticae Koch.) repellency in tomato leaflets with high levels of 2-tridecanone (2-TD) associated to glandular trichomes, we used the advanced lines, 'TOM 600' and 'TOM 601' (high 2-TD levels) 'TOM 584' (control, low 2-TD levels) and the parents 'PI 134417' Lycopersicon hirsutum Dunal var. glabratum (high 2-TD levels) and 'TOM 556' Lycopersicon esculentum Mill. (low 2-TD levels). The experiment was carried out at 16oC and 68% relative moisture. Leaflets of each genotype were placed on a sheet of paper, set on a Styrofoam sheet. Ten female mites were placed on a metallic thumbtack at the center of the leaflets, and the distances the mites moved after 20, 40 and 60 minutes were measured. In general, the distance the mites moved increased according to the time they were left on the thumbtack. The access 'PI 134417', along with the lines 'TOM 600' and 'TOM 601', showed lower distance averages then 'TOM 556' and 'TOM 584'. Those genotypes showed higher repellency, whitch is associated with higher levels of 2-TD.

Keywords : tomato; repellency; allelochemical; 2-tridecanone; spider mite; trichome; resistance.

Acta Bot. Bras., Jan. 2002, vol.16, no.1, p.83-88. (Full text available in Portuguese).