Function of Sitka spruce stone cells as a physical defence against white pine weevil.

Stone cells are a physical defence of conifers against stem feeding insects such as weevils and bark beetles. In Sitka spruce, abundance of stone cells in the cortex of apical shoot tips is associated with resistance to white pine weevil. However, the mode of action by which stone cells interfere with growth and development of weevil larvae is unknown.

Host egg age of Leptoglossus occidentalis (Heteroptera, Coreidae) and parasitism by Gryon pennsylvanicum (Hymenoptera, Platygastridae).

Leptoglossus occidentalis Heidemann (Heteroptera, Coreidae) is native to Western North America and is a serious pest for seed production of conifers. The pest was accidentally introduced into Europe in the 1990s. Since then, seed loss has been recorded in Pinus pinea (L.

Infrared radiation from hot cones on cool conifers attracts seed-feeding insects.

Foraging animals use diverse cues to locate resources. Common foraging cues have visual, auditory, olfactory, tactile or gustatory characteristics. Here, we show a foraging herbivore using infrared (IR) radiation from living plants as a host-finding cue.

(3Z,6Z,9Z, 12Z, 15Z)-Pentacosapentaene, a key pheromone component of the fir coneworm moth, Dioryctria abietivorella.

The sex pheromone of the fir coneworm moth consists of a blend of (3Z,6Z,9Z,12Z,15Z)-pentacosapentaene and (9Z, 11E)-tetradecadienyl acetate. Analogous blends of polyunsaturated, long-chain hydrocarbons with much shorter chain aldehydes or alcohols recently have been discovered in three other moth species in the superfamily Pyraloidea. These combinations of components from two distinct structural classes may represent an important and widespread new pheromone blend motif within the Lepidoptera.