Poster Presentation Science Protecting Plant Health 2017

Correlation between Gonipterus sp. herbivory and leaf oil profiles in Corymbia species and hybrids (#101)

Flavia FB Bonora 1 , David DL Lee 1 , Helen HN Nahrung 1 , Andrew AH Hayes 1
  1. Forest Industries Research Centre - FIRC, University of the Sunshine Coast - USC, Sunshine Coast, Queensland, Austrália

Corymbia species and hybrids are promising for industrial plantations as they suit a vast range of site conditions, showing desirable traits including good field performance and wood characteristics. However, the expansion of planted area may increase the incidence of herbivory and contribute with the emergence of new pests. A major challenge for the forest sector is to select varieties with considerable resistance to pests, while still preserving productivity and market competitiveness. Breeding programs are generally based on field observations of mature trees without considering natural plant defences, such as leaf oil, which may provide an opportunity to select resistant genotypes for industrial plantations. This research aims to improve the Corymbia breeding program by focusing on pest resistance in seedlings. To determine the correlation between Gonipterus sp. herbivory and leaf oil profile, 13 resistant and 12 susceptible taxon of Corymbia were evaluated. Leaf oil was extracted from each taxon with hexane in five replications and the profiles were obtained by GCMS. For the herbivory trial one leaf of each taxon were placed in a petri dish with two Gonipterus sp. beetles in five replications. The herbivory trial run for 7 days under controlled temperature (20 ºC 14 hours light: 10 hours dark) and leaf area before and after herbivory and beetle mortality were determined. The leaf oil profiles were analyzed to see if they influenced herbivory by the Gonipterus sp. beetles.