Studies on the plasticulture using specific UV-blocking films

黄瓜(Cucumis sativus L. cv。‘Hiryu’)和番茄(Lycopersicon esculentum L. cv。在四种不同的聚烯烃薄膜温室（厚度为0.15μm）中种植“Momotaro”植物，分别阻挡了短于400、360、350和340 nm的紫外线波长（特定的紫外线阻挡）。以标准聚烯烃薄膜温室为对照。与在温室外照射植物相比，在对照温室下约有50%的紫外线能量被阻挡。然而，在部分紫外线阻挡条件下，超过70%的紫外线能量被阻挡。幼苗的株高在不同处理之间没有差异，与作物无关。9种不同的昆虫被捕获在胶膜上。其中，黄色胶膜主要捕获蝇类、稻跳虱、粉虱和蚜虫，蓝色胶膜主要捕获食蚜蝇。特异性防紫外线膜的防蚜效果最明显，随着防紫外线率的增加，累计捕获的蚜虫数量明显减少。另外，还检测了特定uv阻隔塑料薄膜对黄瓜叶片蚜虫的防治效果。8月24日- 9月14日，在标准塑料薄膜下，侵染率迅速上升，9月21日达到54%，而在特定的防紫外线条件下，侵染率明显受到抑制，随着防紫外线率的增加，侵染率逐渐下降。我们的研究结果表明，特定的紫外线阻挡塑料薄膜在商业上是可接受的，可以促进害虫综合治理（IPM）系统，特别是在不损害植物生长的情况下控制蚜虫。

Cucumber(Cucumis sativus L. cv.'Hiryu') and tomato(Lycopersicon esculentum L. cv.'Momotaro') plants were grown under four different polyolefin film greenhouses(0.15μm thickness) where UV wavelengths shorter than 400, 360, 350 and 340 nm, respectively, were blocked(specific UV blocking). A standard polyolefin film greenhouse was used as control. Approximately 50% of UV energy was blocked under the control greenhouse compared with that irradiating plants outside the greenhouse. Under partial UV blocking conditions, however, more than 70% of UV energy was blocked. The plant height of the seedlings did not differ among treatments, irrespective of crop. Nine different insects were captured on the adhesive films. Among these, fly, rice plant hopper, whitefly and aphid were mainly captured on yellow adhesive films, while hoverfly was mainly captured on blue adhesive films. Effects of specific UV-blocking films were the most obvious for aphid control, and the cumulative number of captured aphids decreased greatly as the rate of UV-blocking increased. Effect of specific UV-blocking plastic films was also detected on aphid infestation on the cucumber leaves. Under standard plastic film, the infestation rate increased rapidly from 24 August to 14 September, reaching 54% on 21 September, while it was significantly inhibited under specific UV-blocking conditions and the rate decreased gradually as the UV-blocking rate increased. Our results showed that specific UV-blocking plastic films are commercially acceptable for promoting Integrated Pest Management(IPM) system especially for aphid control without harming plant growth.