Ultraviolet-absorbing plastic sheets protect crops from insect pests and from virus diseases vectored by insects

Crops grown in walk-in tunnels covered with UV-absorbing plastic sheets were highly protected from infestation with sweetpotato whitefly, Bemisia tabaci (Gennadius); western flower thrips, Frankliniella occidentalis (Pergande); and cotton aphid, Aphis gossypii Glover. Protection against B. tabaci was associated with a dramatic reduction in the spread of the whitefly-borne geminivirus tomato yellow leaf curl (TYLCV) and with a pronounced delay in plant infection and disease severity. Two months after transplantation, the average TYLCV disease incidence under 3 different UV-absorbing plastic sheets was 50, 30, and 20% compared with 93% under W-nonabsorbing polyethylene sheets. In additional experiments, it was shown that the UV-absorbing sheets were also highly effective in the protection of cucumbers against F. occidentalis and A. gossypii. Filtration of full spectrum and monochromatic UV light by W-absorbing plastic sheets reduced significantly the attraction of B. tabaci to these light sources. The association of the described phenomena with the UV vision of insects is discussed.