Insects associated with fruit, seed and foliage of Uapaca kirkiana (Muell.arg.) (Euphorbiaceae) in Malawi

[摘要] ENGLISH ABSTRACT: Arthropods associated with Uapaca kirkiana in Dedza and Zomba, Malawi, werecollected during October 1996, January 1997, June 1997 and August 1997 using variouscollection methods including beating, sweepnets, suction using an aspirator and collection ofparts of plants with endogenous arthropods or on which external sessile arthropods wereattached. A total of 12,849 arthropods were collected and sorted into 10 orders, 40 familiesand 51 morphospecies. Arthropod diversity was high in Dedza, but the few arthropodsspecies that occurred in Zomba had more individuals per species. More arthropods wererecorded on trees growing in woodlands dominated by either large or small Uapaca trees.Leafchewers and sapsuckers comprised the majority of the arthropods collected. Highestarthropod counts were registered in October 1996 and lowest in June1997.Six arthropod morphospecies namely Phycitidae (undetermined species), white scales(undetermined species), Gelechiidae (undetermined species), Lasiocampidae (undetermined),Bunaea alcinoe (Saturniidae) and Leptoglossus membraceus (Heteroptera) were observedcausing significant damage. The other species were either natural enemies or did notsignificantly affect U. kirkiana trees. Most arthropod damage was observed on individualtrees on the farm and in woodlands dominated by either large or small Uapaca trees.The low arthropod incidence and arthropod damage on U. kirkiana in mixed woodlandand fire prone areas suggest that mixed woodland is the best option for managing U. kirkianaand that early controlled fire can also be used to minimize pests. The large number ofarthropods without a direct effect on U. kirkianaunderlines the role of this tree as analternative or alternate host to pests of associated crops.

[发布机构] Stellenbosch University