Short-distance Walking Responses of Thrips palmi KARNY(Thysanoptera:Thripidae)to Tomato Leaves

Thrips palmi attacks a wide range of vegetables but excludes tomato plants. In our preliminary attempts to clarify tomato immunity to this particular species, we found that the adult insects invade green-houses without prior discrimination of vegetables grown within. This fact shows that they do not use airborne chemical cues of plant origin in long-distance searches for food plants. However, it is still not known if there are some phytochemical cues contributing to short-range host searches. To solve this problem, experiments on their short-distance orientation were conducted.