LABORATORY FEEDING AND COLONIZATION OF NON-HOST LODGEPOLE PINE BY TWO POPULATIONS OF PISSODES STROBI (PECK) (COLEOPTERA: CURCULIONIDAE)

Abstract

AbstractTwo populations of Pissodes strobi (Peck), one from Sitka spruce, Picea sitchensis (Bong.) Carr, and the other from Engelmann spruce, Picea engelmannii Parry ex Engelm., were successfully induced to oviposit on the non-host lodgepole pine, Pinus contorta Dougl. var latifolia. The number of egg punctures excavated on the non-host was smaller than that on either Sitka or Engelmann spruce. Survival from egg to adult was similar on the non-host and the host trees. The two weevil populations differed in the degree to which lodgepole pine met the nutritional requirements for weevil development, as measured by weight of weevils and developmental time from egg to adult. In choice-feeding experiments, weevils reared in lodgepole pine rejected this species and chose Sitka spruce, suggesting that feeding preference in P. strobi is genetically fixed and therefore cannot be changed by rearing the insects on the non-host tree. The importance of these findings is discussed in relation to the idea of weevil control through the development of weevil-resistant varieties.