| Title: | Impact of reassociation with a coevolved herbivore on oviposition deterrence in a hostplant |
| Author(s): | Jogesh T; Wong JC; Stanley MC; Berenbaum MR; |
| Address: | "Department of Entomology 320 Morrill Hall, University of Illinois at Urbana-Champaign, 505 S. Goodwin, Urbana, IL, 61801-3795, USA, tania.jogesh@gmail.com" |
| DOI: | 10.1007/s00442-014-2999-2 |
| ISSN/ISBN: | 1432-1939 (Electronic) 0029-8549 (Linking) |
| Abstract: | "Although selection by herbivores for increased feeding deterrence in hostplants is well documented, selection for increased oviposition deterrence is rarely examined. We investigated chemical mediation of oviposition by the parsnip webworm (Depressaria pastinacella) on its principal hostplant Pastinaca sativa to determine whether ovipositing adults choose hostplants based on larval suitability and whether hostplants experience selection for increased oviposition deterrence. Webworms consume floral tissues and florivory selects for increased feeding deterrents; moths, however, oviposit on leaves of pre-bolting plants. Exclusive use of different plant parts for oviposition and larval feeding suggests oviposition should select for increased foliar deterrents. Recent webworm colonization of New Zealand (NZ) allowed us to assess phenotypic changes in foliar chemicals in response to webworm oviposition. In a common garden experiment, we compared NZ populations with and without a history of infestation from 2004 to 2006 for changes in leaf chemistry in response to oviposition. Three leaf volatiles, cis- and trans-ocimene, and beta-farnesene, elicit strong responses in female moth antennae; these compounds were negatively associated with oviposition and are likely oviposition deterrents. Leaf beta-farnesene was positively correlated with floral furanocoumarins that deter florivory; greater oviposition on plants with low floral furanocoumarins indicates that moths preferentially oviposit on parsnips most suitable for larval growth. Unlike florivory, high oviposition on leaves did not lower plant fitness, consistent with the fact that NZ parsnip foliar chemistry was unaffected by 3-6 years of webworm infestation. Thus, in this system, selection by ovipositing moths on foliar chemistry is weaker than selection by larvae on floral chemistry" |
| Keywords: | "Animals *Biological Evolution Chromatography, Gas Furocoumarins/metabolism Herbivory/*physiology Illinois *Introduced Species Moths/*physiology New Zealand Oviposition/*physiology Pastinaca/*parasitology Plant Leaves/metabolism Sesquiterpenes/metabolism;" |
| Notes: | "MedlineJogesh, Tania Wong, Joseph C H Stanley, Margaret C Berenbaum, May R eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Germany 2014/07/06 Oecologia. 2014 Sep; 176(1):117-27. doi: 10.1007/s00442-014-2999-2. Epub 2014 Jul 3" |
