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I am specifically interested in the chemical interactions of forest trees with insects and microorganisms. My research combines methodologies from diverse fields of specialization, including ecology, natural product biosynthesis and analysis, enzymology, genetics, plant physiology, genetic engineering and microbiology.

In trees, chemical signals are used for communicating with pests and pathogens as well as with beneficial organisms. In some cases, the chemical makeup of a tree tells the pest or pathogen that the tree is a good food source that can be utilized for its own survival and spread. In other cases, specific chemicals can stop an attack by a pathogen or insect due to its toxicity or its bad taste. My research is focused on unravelling the chemical signals of plantation trees and to study which chemical signals are beneficial or detrimental to important South African forestry pests and pathogens. Following analysis of many different varieties and species, the goal is to identify compounds in Eucalyptus, pine or wattle that stimulate and deter insect feeding or pathogen infection. These data can then be used to make accurate predictions on how resistant each variety is to a pest or pathogen. This research can be applied for tree breeding, by creating chemical marker panels for each tree genus (pine, eucalypt or wattle), where a simple chemical analysis can reveal the likelihood of susceptibility or resistance of a newly developed variety to multiple different pests and pathogens. These chemical marker panels do not rely on labor intensive screening trials or subjective measurements and are less costly than other screening methods. The material used for the analyses can be as small as a single detached leaf, and thus the logistics to grow and transport material for the analyses is straight forward.

In addition to the chemical analysis, we are also working on developing methods and models for using spectral techniques, such as NIRA, for distinguishing resistant from susceptible varieties. This non-destructive diagnostic methodology can also be used to identify diseased plants, such as Phytophthora infection of Eucalyptus roots. This project has enormous potential for transferring the capacity identify early pathogen infection to commercial nurseries and farmers.