High Concentrations of Very Long Chain Leaf Wax Alkanes of Thrips Susceptible Pepper Accessions (Capsicum spp)
The cuticular wax layer can be important for plant resistance to insects. Thrips (Frankliniella occidentalis) damage was assessed on 11 pepper accessions of Capsicum annuum and C. chinense in leaf disc and whole plant assays. Thrips damage differed among the accessions. We analyzed the composition of leaf cuticular waxes of these accessions by GC MS. The leaf wax composition was different between the two Capsicum species. In C. annuum, 1 octacosanol (C28 alcohol) was the most abundant component, whereas in C. chinense 1 triacotanol (C30 alcohol) was the prominent. Thrips susceptible accessions had significantly higher concentrations of C25 C29 n alkanes and iso alkanes compared to relatively resistant pepper accessions. The triterpenoids a and ss amyrin tended to be more abundant in resistant accessions. Our study suggests a role for very long chain wax alkanes in thrips susceptibility of pepper. Electronic supplementary material The online version of this article (10.1007/s10886 020 01226 x) contains supplementary material, which is available to authorized users.
Journal of chemical ecology