Trichomes and hydrocarbons associated with the tomato plant antixenosis to the leafminer

Abstract

The objective of this work was to study the density of trichomes and hydrocarbons associated with the resistance by antixenosis of 42 subsamples of tomato plants from the Horticultural Germplasm Bank of the Universidade Federal de Viçosa (HGB-UFV) to Liriomyza trifolii. These subsamples were studied in addition to 'Santa Clara' cultivar, which was used as a standard of susceptibility to leafminers. The evaluated characteristics were the number of mined leaflets per plant, mines per plant, trichome density and chemical compounds in the leaves. Differences were detected among the subsamples in the variables studied. We identified 20 peaks in the chromatograms of leaf hexane extract the subsamples tested. The subsamples HGBs -216, 813, 985, 987, 991, 992, 993, 1532HGBs -216, 813, 985, 987, 991, 992, 993, , 1989HGBs -216, 813, 985, 987, 991, 992, 993, , 1991HGBs -216, 813, 985, 987, 991, 992, 993, , 2048HGBs -216, 813, 985, 987, 991, 992, 993, , 2055HGBs -216, 813, 985, 987, 991, 992, 993, , 2064HGBs -216, 813, 985, 987, 991, 992, 993, , 2068HGBs -216, 813, 985, 987, 991, 992, 993, , 2073HGBs -216, 813, 985, 987, 991, 992, 993, , 2075HGBs -216, 813, 985, 987, 991, 992, 993, , 2089HGBs -216, 813, 985, 987, 991, 992, 993, , 2096HGBs -216, 813, 985, 987, 991, 992, 993, and 2097 were selected as sources of resistance to L. trifolii. The resistance mechanism associated to these subsamples was antixenosis. In addition, the low density of trichomes and the chemical compounds in the subsamples can be possible causes of pest resistance.

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) on the “Offensive” in Africa: Prospects for Integrated Management Initiatives

“…While few moderately resistant tomato cultivars have been reported [197,198], the majority are highly susceptible to T. absoluta infestation. Three mechanisms may account for plant resistance to insect attack, namely antixenosis, antibiosis and tolerance [199]. Thus, tomato cultivars significantly differ in their susceptibility to T. absoluta [200][201][202][203], and that resistance is positively associated with trichomes density and the diversity and concentrations of host secondary metabolites [201,202,204].…”

Bottom-up effects of irrigation, fertilization and plant resistance on Tuta absoluta: implications for Integrated Pest Management

“…Constitutive resistance traits -In wild tomato species, plant resistant traits to T. absoluta are mainly related to the type and density of leaf trichomes (Fernandes et al 2012;Sohrabi et al 2016Sohrabi et al , 2017 and the compounds produced and stored inside. Both provide a constitutive protection against the leafminer since contact with the leaf is a key component for inducing T. absoluta oviposition (Proffit et al 2011).…”

Integration of resistant variety and biological agent to control tomato leaf miner,Tuta absoluta(Meyrick), under greenhouse conditions

“…The differences in host suitability for tomato leafminer were reported in earlier studies (Gilardón et al ., 2001; Leite et al ., 2001; Gharekhani and Salek-Ebrahimi, 2014; Sohrabi et al ., 2016, 2017). Genetic variability was reported as the main characteristic which influences higher or lower host susceptibility to pests (Fernandes et al ., 2012). Physical and chemical barriers especially density and composition of type VI glandular trichomes were reported as important factors in cultivated tomato which adversely influence reproduction and development of insects and mites (Saeidi and Mallik, 2012).…”