@article{oai:u-ryukyu.repo.nii.ac.jp:02002712, author = {平川, 守彦 and 富名腰, 道子 and 日越, 博信 and 大城, 政一 and 石嶺, 行男 and 平山, 琢二 and 赤嶺, 光 and 外間, 聡 and Hirakawa, Morihiko and Funakoshi, Michiko and Higoshi, Hironobu and Oshiro, Seiichi and Ishimine, Yukio and Hirayama, Takuji and Akamine, Hikaru and Hokama, Satoshi}, issue = {45}, journal = {琉球大学農学部学術報告, The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus}, note = {本研究は, 放牧地空間を有効利用するために, 放牧草地生態系へ熱帯果樹を導入することによって, 肉生産と果樹生産の両立をはかることを目的としている。昨年放牧牛による食害防御法が確立されたことからその方法であるワイヤーメッシュケージ法を継続して行ない, さらに果樹の生長, 果実の生産に向けて生育状況を把握するとともに効率良く生産をおこなうため, 放牧地の種々の光条件下と地形の違いによる果樹の生育について調査, 検討を行なった。昨年からのワイヤーメッシュケージ法を継続して行ない, グアバとビワのうち枯死していないもの(グアバ96本・ビワ64本)を調査に用いた。供試家畜は, 黒毛和種の成牛4頭と子牛4頭の合計8頭を用いた。グアバ, ビワの両果樹それぞれについて相対照度を測定し, 相対照度が100%∿65%の所をH区, 相対照度が65%∿35%の所をM区, 相対照度が35%以下となる所をL区と設定し, グアバについてはさらに傾斜角度が約35度の北西斜面の傾斜地をN区と設定した。調査項目は, 放牧牛による果樹の被食率, 麻袋被害率, 果樹の葉数, 果樹の樹高で, 調査期間は6月から12月までで1ヶ月間隔で調査を行なった。ワイヤーメッシュケージを継続して行なったところ, 調査期間全体を通して両果樹とも放牧牛による被食率は0%であった。麻袋被害率についてもほとんど0%であったが調査期間中の平均被害率がグアバ区で7.7%, ビワ区で0.6%と有意な差が認められた。相対照度の調査において, グアバではH区で葉数, 樹高ともに一番高い値を示し, L区で葉数,樹高ともに有意に低い値が認められた。グアバ区では病害虫の発生もみられ生長は思わしくなかった。ビワではL区で葉数, 樹高ともに一番高い値を示した。ビワ区ではわずかではあるが生長が認められた。両果樹について台風による被害がみられた。, We had studied on the introduction of tropical fruit tree in grazing pastute to produce both beef and tropical fruits because of utilization space in grasslands. We reported that several methods were conducted to introduce various tropical fruit trees (papaya, guava, loquat) in grasslands. We established the protection method for fruit trees from grazing cat tle; that was the wire-mesh cage method surrounded tropical tree by the wiremesh cage. So we continued the study to investigate the growth of guava and loquat using this method under various intensity of illuminations and topography. A guava (Psidium guyava L.) and loquat (Eriobtrya japonica Lindley) were transplanted in 1996. Eight heads of Japanese black cattle; four cows and four calves were grazed in grassland. The grasslands with the guava and loquat trees were divided into three plots of intensity of illuminations which were high intensity of 100-65% (H), of midium intensity of 65-35% (M), and of less than 35% (L), and then plotted the northwest-facing slope plot (N) in grasslnad with guava trees. We investigated the ratio of damage of fruit trees and of mulching materials (used linen bags) under the trees by grazing catlle, number of their leaves and height of trees from June to December every month. Tropical fruit trees were not entirely injured by grazing cattle during whole experimental periods by wire-mesh cage method. However, there was a small damage of mulching linen bags in guava area (7.7%) and loquat area (0.6%), it was singnificant at 5% level. The number of leaf and the height of guava were the highest in the high intensity of illumination area, but their values were lower in the less than 35% area. Only guava trees were damaed by insects (larvae of moth). On the contrary the number of leaf and the height of loquat trees showed the highest value in the intensity of illumination of less than 35% area. We found a typhoon da-maged the guava and loquat furuit trees., 紀要論文}, pages = {43--51}, title = {放牧地への熱帯果樹導入に関する研究 : V. 放牧地における光強度と地形が熱帯果樹の生育に及ぼす影響} }