The sweetpotato whitefly Bemisia tabaci is a serious pest and virus vector of many crops. To understand thermal tolerance of B. tabaci at molecular level, effects of rapid and acclimated thermal stress were analyzed by measuring mRNA levels of two heat shock proteins (hsp), hsp23 and hsp90, of B. tabaci using quantitative real-time RT-PCR. Mortality of adult whiteflies were 65.5% by 45°C for 1 h but 100% by 50°C for 1 h. However, mortality by subsequent exposures to 35°C for 1 h then 45°C for 1 h was 43.3%. Comparison between rapid and acclimated heat shock treatments showed that different patterns between hsp23 and hsp90 levels. At acclimated condition, hsp90 was higher but hsp23 was lower than rapid heat shock. The results suggest that the heat acclimation response is possibly advantageous to whiteflies that are often exposed to drastic temperature fluctuations.

• Pijush Kanti Jhan(College of Agriculture and Life Sciences, Kyungpook National University)
• Jae-Kyoung Shim(College of Agriculture and Life Sciences, Kyungpook National University)
• Kyeong-Yeoll Lee(College of Agriculture and Life Sciences, Kyungpook National University Institute of Plant Medicine, Kyungpook National University)