Response of adult New Zealand flower thrips, Thrips obscuratus (Thysanoptera: Thripidae) to high carbon dioxide and low oxygen atmospheres at various temperatures

Mortality responses of adult New Zealand flower thrips, Thrips obscuratus (Crawford) to controlled atmospheres were assessed. Temperature (0-48 degrees C) and time (1-24 h) had major effects on mortality. There were approximately two-fold increases in thrips mortality between atmospheres with 40 and 60% CO2, when there was 0 or 2% O-2 present in treatments of 0 degrees C for 4 h and 24 h; 12 degrees C for all exposure times; 24 degrees C for 1 h. Thrips mortality was significantly greater when there was no O-2 in the test atmosphere, than when there was 0.25, 8 or 12 or 20% O-2. The results show that there are a variety of ways produce infested with New Zealand flower thrips could be treated with controlled atmospheres to achieve high mortality. These data can be used as the basis of potential quarantine treatments depending on the produce being exported.