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RESEARCH INTERESTS
Host plant resistance; Insect ecology and behavior
-Thrips pollination of Macrozamia cycads of Australia:
implications for conservation and evolution of pollination systems in cycads
-Thrips host plant selection and behavior
-Soybean insect resistance quantitative trait loci
PUBLICATIONS
My current interests focus around the biology, behavior and evolution of
insect order Thysanoptera (thrips). Within this order of insects of
approximately 5000 species world-wide, there is a remarkable diversity of life styles and social behaviors, including spore and fungal feeding, plant and pollen feeding, predatory and parasitic life styles, and several levels of social behavior. We are studying the divergence of life history traits among Thysanoptera, particularly, the behaviors and morphology associated with mate and host selection processes that might lead to differences in social behaviors.
During field studies in 1999, we established that members of a recently described thrips genus, Cycadothrips spp., in a basal clade of Thysanoptera, are specialist pollinators of some Macrozamia spp. cycads in Australia. All other cycads studied to date are thought to have beetles (or possibly wind) as pollen vectors. Because cycads are a basal clade within extant gymnosperms, thrips may have played a greater role in the early evolution of pollination systems than expected based on the current knowledge of thrips as pollinators of angiosperms. We are now investigating the extent to which thrips are pollinators of cycads, the cues thrips use to find male and female cycad cones, and the evolutionary relationships of this thrips genus to its presumed closest relatives which are found in the western Americas.
In collaboration with Gordon Lark, we have also been studying the genetics of insect resistance in soybean using different sets of recombinant inbred lines, that are genetically mapped with molecular markers. Previous studies suggested that resistance in soybeans result from quantitative traits. We predicted, therefore, that some recombinant inbreds, derived from non-resistant parents with different genetic backgrounds, would be highly resistant and others would be much more susceptible than their parents. This was indeed the case with inbreds derived from the cross of parents Minsoy and Noir1 from China and Hungary. Individual lines from this population were tested for their effects on several insect herbivores, including many polyphagous and oligophagous insect pest species. We found four quantitative trait loci (QTLs) on different linkage groups associated with large effects (four to eight- fold differences) on larval weight and development. Some of these same loci, as well as several additional ones, affect pupal weight, food utilization efficiency, and larval mortality. Some of these insect resistance QTLs have been confirmed using an independent population of recombinant inbred lines with a different genetic background, while other QTLs appear to operate only in specific backgrounds. We have determined that both plant morphological and chemical traits are associated with this resistance.
Selected references
Terry, L. I. 2001. Thrips and weevils as dual, specialist pollinators of the Australian cycad Macrozamia communis (Zamiaceae). International Journal of Plant Sciences. in press
Mound, L. and I. Terry 2001 Thrips pollination of the central Australian cycad, Macrozamia macdonnellii (Cycadales). International Journal of Plant Sciences 162: 147-154.
Terry, I. 1997. Host selection, communication, and reproductive
behaviour. pp 64-118 in Lewis, T. (ed.) Thrips as crop pests. CAB
International, London.
Terry, I. and E. Dyreson. 1996. Behavior among Frankliniella
occidentalis (Thysanoptera: Thripidae) males within aggregations, and morphometric correlates of fighting. Ann. Entomol. Soc. Amer. 89: 589-602.
Terry, L. I. K. Chase, T. Jarvik, J. Orf, L. Mansur, and K. G. Lark. 2000. Quantitative trait loci for soybean resistance to insects. Crop Science 40: 375-382.
Terry, I. , K. Chase, J. Orf, T. Jarvik, L. Mansur, and G. Lark. 1999. Insect resistance in recombinant inbred soybean lines derived from non-resistant parents. Entomologia Experimentalis et Applicata 91: 465-47.
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