Application of the electronic nose to the classification of resistance to Western flower thrips in chrysanthemums.

A metal oxide sensor-based electronic nose was tested for its ability to discriminate among chrysanthemum cultivars with varying degrees of resistance to western flower thrips (WFT), based on volatile chemicals released from cut leaves. Cultivars that were susceptible, intermediate, or resistant to WFT [based on mean cultivar rank (MCR)] were used as standards, and were correctly classified (> 90%) by using discriminant function analysis. Several cultivars with unknown resistance were classified based on the standards, and were used as standards in a subsequent trial to classify other unknowns. The results of this study demonstrate some agreement between the WFT resistance categories as designated by the electronic nose and results of feeding bioassays (MCR), suggesting that this technique may serve as a useful screening tool for WFT resistance.