Foliar and cortical monoterpenes in Sitka spruce: potential indicators of resistance to the white pine weevil, Pissodesstrobi Peck (Coleoptera: Curculionidae)

Abstract

To determine whether a resistant chemotype to the white pine weevil, Pissodesstrobi Peck, could be identified, the relative composition of monoterpenes in weevil-susceptible Sitka spruce, Piceasitchensis (Bong.) Carr., was compared to that in apparently resistant trees. Foliar and cortical analysis of trees from Green Timbers Nursery in Surrey, Nootka Island, Sayward, and the Nass River Valley, B.C., revealed significant differences between 38 resistant and 60 susceptible trees. The foliage of resistant trees, compared with that of susceptible trees, had significantly lower amounts of isoamyl isovalerate at three sites and lower amounts of isopentenyl isovalerate at one site. Amounts of a α-pinene, β-pinene, camphene, and camphor were significantly higher in some resistant trees, but these differences were not consistent between sites. Myrcene, β-phellandrene, and limonene levels were much higher in the cortex of susceptible trees than the resistant trees from the Nass River and Green Timbers Nursery. Thus none of the monoterpenes, singly or in combination, is a consistent indicator of resistance to the white pine weevil. The two isovalerates could possibly be used as indicators of resistance. However, a broader spectrum of resistance characteristics should be employed if breeding for resistance is desired.

Applications of terpene analysis in forest genetics

“…Nevertheless, genetic variation among trees is clearly discemable despite large within-tree changes, and after periods of rapid development such as during bud-burst, concentrations always return to a base level characteristic of the tree and tissue. Similar conclusions were drawn in studies by Brooks et al (1987) comparing foliar and bud monoterpenes in Picea sitchemis; von Rudloff (1972Rudloff ( , 1975b also working with Piceu pungens and Picea gluucu (Moench) Voss; Kossuth and Muse (1986) with Pinus elliotii; Bernard-Dagan (1987) with Pinus pinaster Ait. ; and many others.…”

“…Terpenes have often been studied for their potential role in resistance or susceptibility to attack by diseases, insects, and animals (Whitney and Denyer 1969;Rockwood 1973;Hanover 1975a;Bridgen et al 1979b;Harris et al 1983;Raffa et al 1985;Wilkinson 1985;Reed et al 1986;Brooks et al 1987;and Michelozzi et al 1990). In several of these cases rather clear associations have been found between terpenes and pest attack, and the use of terpenes for indirect selection to enhance resistance has been suggested (Rehfeldt and von Rudloff 1978;Bridgen and Hanover 1982b;Hanover 1983).…”

The impact of host plant species on the larval development of the large pine weevil Hylobius abietis L.

“…It is possible that unmeasured qualitative differences in polyphenolic compounds between and within the host species affected larval development. Qualitative variation in polyphenolic (Brignolas et al ., 1998) and resin (Bridgen et al ., 1979; Brooks et al ., 1987) constituents, between and within spruce species has been found to affect significantly the feeding ecology of bark beetles. The analytical methods used in these experiments, however, were solely quantitative, not qualitative, and more elaborate assays were beyond the scope of this study.…”

Variation of leaf gland volatile oil within a population of sweet gale (Myrica gale) (Myricaceae)

“…Terpenes have been associated with antimicrobial activity (Macht & Kunkel 1920;Maruzzella 1962Maruzzella , 1963aMaruzzella et al 1963;Morris et al 1978;McDowell et al 1988) including inhibition of gut flora in ruminants (Nagy & Tengerdy 1968;Oh et al 1967Oh et al , 1968, with insect deterrence (Berryman 1969;Brooks et aL 1987;Cates et al 1987;Mihaliak et al 1987) and with mammalian herbivore deterrence (Scholl et al 1977;Elliot & Loudon 1987). The dihydrochalcones of sweet gale also have marked antimicrobial activity (Malterud & Faergi 1982).…”