Abstract
We examined the impact of artificial UV-B radiation control of the spider mite Tetranychus ludeni on the growth of melon plants. The mite densities on greenhouse melon plants were well controlled by the combination of 2.16-4.32 kJ m-2 UV-B radiation at night and a reflective sheet mulch. The leaf area of melon plants in the plot receiving 2.16 kJ m-2 UV-B radiation in combination with a reflective sheet mulch did not differ from that in the control plot, whereas leaf area was significantly reduced in the 4.32 kJ m-2 UV-B radiation plot. On the basis of these results, we suggest there is potential for controlling spider mites by UV-B radiation of greenhouse melon. In order to devise a suitable control system, further studies will be necessary to elucidate the optimum radiation conditions.
