title: Trade-offs between constitutive and induced resistance in wild crucifers shown by a natural, but not an artificial, elicitor.
abstract: Constitutive and induced plant resistance against herbivores occurs throughout the plant kingdom, but little is known about the evolutionary relationship between these two types of resistances. We examined the relationships between constitutive and induced resistance to the diamondback moth, Plutella xylostella, in 11 wild species of crucifers, and analyzed the changes in volatiles associated with their expression in two species. We used larvae of P. xylostella and jasmonic acid (JA) as elicitors of the induced response. The level of resistance was estimated as the relative number of eggs laid on the plants by P. xylostella. Substantial variation in constitutive resistance was observed among the 11 crucifer species. When the plants were damaged by larvae, a negative correlation was found between constitutive and induced resistance. However, a positive correlation was detected between constitutive and induced resistance when the plants were treated by JA. The shift in resistance was associated with changes in the emission of volatiles. These results strongly suggest that (1) a trade-off occurs between constitutive and induced resistance in wild crucifers, and that (2) such a trade-off can be observed by treating the plants with a natural, but not an artificial, elicitor.
authors.affiliation: Institute of Insect Sciences, Zhejiang University, 268 Kaixuan Road, 310029 Hangzhou, China.
authors.forename: Peng-Jun
authors.initials: PJ
authors.lastname: Zhang
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Shu
authors.forename: Cheng-Xin
authors.initials: CX
authors.lastname: Fu
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Ying
authors.initials: Y
authors.lastname: Hu
authors.forename: Myron P
authors.initials: MP
authors.lastname: Zalucki
authors.forename: Shu-Sheng
authors.initials: SS
authors.lastname: Liu
mesh_terms: D000818:Animals; D019607:Brassicaceae / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D003463:Cues; D003517:Cyclopentanes / Q000494:pharmacology*; D005247:Feeding Behavior; D005260:Female; D009036:Moths / Q000502:physiology*; D010058:Oviposition; D054883:Oxylipins / Q000494:pharmacology*; D014835:Volatilization
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; C011006:jasmonic acid