The effects of plant growth conditions (light intensity. temperature and photoperiod) on the proportion of spider mites (Tetranychus urticae) and predatory mites (Phytoseiulus persimilis) entrapped by type VI trichomes were investigated in the cultivated tomato Lycopersicon esculentum. Trichomes released sticky substances showing rapid hardening when the trichome head was ruptured by contact with mites. Adult individuals of both species of mites were immobilized by exudates in a higher percentage on leaf stalks from plants grown in the light (160 mueinsteins cm-2 s-1) than on leaf stalks from plants grown in the shade (50 mueinsteins cm-2 s-1). Leaf stalks from plants grown in the light showed bigger trichome heads. More predatory mites were also entrapped on the leaf stalks from plants grown at 18-degrees-C (65% RH) as compared to the ones grown at 24-degrees-C (60% RH). whereas trichome heads were bigger under the former conditions. Contrary to leaf stalks. leaflet areas, through differences in trichome density and size, showed no differences in predator and spider mite entrapment. Trichome head size was probably related to mite entrapment. It is also hypothesised that temperature increase might influence predator entrapment through effects on trichome quality.
Nihoul, P. (1993). Do Light-intensity, Temperature and Photoperiod Affect the Entrapment of Mites On Glandular Hairs of Cultivated Tomatoes. Experimental & Applied Acarology, 17(9), 709-718. https://hdl.handle.net/2078.5/43728 (Original work published 1993)