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Larvae of the pine beauty moth Panolis flammae (Denis & Schiffermüller) were reared in sleeve cages on five different seed origins (provenances) of pole stage Pinus contorta in the field in each of four years from 1985 to 1988. Survival varied significantly between the years. In those years when survival was high, Significant differences between tree provenance were not found. However, between provenance significant differences were found in larval weight and stage of development. In the years when survival was low, the results seen in good years were reversed. significant differences attributable to provenance were found but these were not reflected in significant differences between larval weight or development. In addition, there was a significant correlation between the proportion surviving and larval weight, which was not the case in those years where larval survival was high. The results are discussed in light of the pest status of P. flammea in Britain and in view of current silvicultural policies. The use of trees resistant to insect attack as part of an integrated pest management programme is highlighted and the need to coordinate laboratory and field studies so as to control for environmental variation discussed.

The ability to resist or avoid natural enemy attack is a critically important insect life history trait, yet little is understood of how these traits may be affected by temperature. This study investigated how different genotypes of the pea aphidAcyrthosiphon pisumHarris, a pest of leguminous crops, varied in resistance to three different natural enemies (a fungal pathogen, two species of parasitoid wasp and a coccinellid beetle), and whether expression of resistance was influenced by temperature. Substantial clonal variation in resistance to the three natural enemies was found. Temperature influenced the number of aphids succumbing to the fungal pathogenErynia neoaphidisRemaudière & Hennebert, with resistance increasing at higher temperatures (18 vs. 28°C). A temperature difference of 5°C (18 vs. 23°C) did not affect the ability ofA. pisumto resist attack by the parasitoidsAphidius erviHaliday andA. eadyiStarý, González & Hall. Escape behaviour from foraging coccinellid beetles (Hippodamia convergensGuerin-Meneville) was not directly influenced by aphid clone or temperature (16 vs. 21°C). However, there were significant interactions between clone and temperature (while most clones did not respond to temperature, one was less likely to escape at 16°C), and between aphid clone and ladybird presence (some clones showed greater changes in escape behaviour in response to the presence of foraging coccinellids than others). Therefore, while larger temperature differences may alter interactions betweenAcyrthosiphon pisumand an entomopathogen, there is little evidence to suggest that smaller changes in temperature will alter pea aphid–natural enemy interactions.