　カキ平棚仕立て栽培に多目的ネットを被覆し，害虫防除効果および果実品質と次年度の雌花数等への影響について検討した。ネット区では，6月下旬～ 7月上旬から収穫期の11月下旬～12月上旬まで 6× 6mmおよび 5× 2.5mm目合いのネットを被覆し，殺虫剤の散布回数を減らした。殺虫剤散布回数が 6回のネット被覆区と 10.7回の露地栽培区との比較を行った結果，健全果率は露地と同等であった。ネット被覆区ではカメムシの被害が減少し，被害抑制効果が認められたが，フジコナカイガラムシによるすす病果の発生が増加傾向にあり被害抑制効果はなかった。また，ネット被覆によって月平均温度や湿度はほぼ変わらなかったが，相対照度は20％程度減少した。しかし，果皮色，果実品質，収量，次年度の雌花数に及ぼす影響は小さかった。

　Effects of a Covering Net on Insect Control and Fruit Quality of Japanese Persimmons in a Horizontal Trellis Training System. Kazuya MATSUDA, Hiroyuki FUJISHIMA, Daijiro YAHATA, Kimihiko HAYASHI and Hiroyuki CHIJIWA (Fukuoka Agric. Res. Cent., Chikushino, Fukuoka 818-8549, Japan) Bull. Fukuoka Agric. Res. Cent. 25:77-81 (2006)

　By covering Japanese persimmon trees in a horizontal trellis training system with multi-purpose nets, we examined the influence of the nets on the number of female flowers produced in the following year, the quality of the fruit, as well as the effects of insect control. The net covering was installed from the last ten days of June and the first ten days of July to the last ten days of November and the first ten days of December, which corresponded to the harvesting period. The nets used had 6.0 mm×6.0 mm meshes and 5.0 mm×2.5 mm meshes. After covering, we reduced the number of times of insecticide spraying. Insecticide was sprayed four times less on the covered field compared with the open field; however, the percentages of healthy fruit were the same in both cases. Damage from sting bugs on the covered field was remarkably little; however, damage from the development of sooty mold attributable to Japanese mealybugs tended to increase. By installing the net covering, the average monthly temperature and humidity did not change noticeably but the relative lighting degree was reduced by about 20%. However, the effects were small on skin coloration, fruit quality, the amount of the harvest and the number of female flowers in the following year.