III. Effects of wire-net method on protecting tropical fruit tree from grazing cattle (A study on the introduction of tropical fruit tree in grassland)
| Autor: | Higoshi, Hironobu, Hirakawa, Morihiko, Hasuo, Tamaki, Oshiro, Seiichi, Ishimine, Yukio, Hirayama, Takuji, Akamine, Hikaru, Hokama, Satoshi |
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| Jazyk: | japonština |
| Rok vydání: | 1997 |
| Předmět: | |
| Zdroj: | 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus. 44:153-159 |
| ISSN: | 0370-4246 |
| Popis: | 本研究は放牧地の立体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し, 肉生産と果樹生産を行おうとするものである。本試験において, 食害防御効果を高めるために金網ネットを用いた物理的な方法による熱帯果樹の食害防御法の検討を行った。熱帯果樹にはグアバとビワを用いた。供試家畜は黒毛和種経産牛3頭(平均体重370kg), 未経産牛4頭(生後17∿22ヶ月齢)の合計7頭を放牧した。グアバとビワの苗は放牧地に約4m間隔で移植し, 長さ1.5mの支柱を苗の両側に立て, 上からネット袋で苗を被覆し供試牛を放牧した。退牧時にグアバとビワの被食率とネットの被害率を調査した。ネット試験を2回終了した時点でネットを取り外し, 苗の四方に支柱を4本立て, その支柱に金網ネットを張り巡らし固定した。ネット試験と同様に6回の放牧試験を行った。試験期間は7月から1月までの8ヶ月で8回の放牧試験を行った。1日平均果樹被食率はグアバのネット処理区で4.3%, 金網ネット処理区で1.6%, ビワのネット処理区で1.9%, 金網ネット処理区で0.7%と両果樹とも金網ネット処理区の方が低い値を示した。この結果, 金網ネット処理区はネット処理区に比べ有意に低い値を示した。また, グアバとビワにおける被食率の差も検討したが, 有意な差は認められなかった。以上の結果より, 金網ネット処理はネット処理に比べ熱帯果樹食害防御効果の高いことがわかった。 We have studied to produce both beef and tropical fruit due to utilization of spatial space in grassland. In this study we attempted the method of wirenet to protect tropical fruit tree from grazing cattle. We cultivated guava and loquat as tropical fruits, and grazed seven Japanese black cattle; three cows of mean weight of 370kg, four heifers of the range from seventeen to twenty-two months. We transplanted guava and loquat at four meter intervals in grassland, and struck the steel pole which was 1.5m in length both sides of a tropical fruit tree. All the tropical fruit trees (guava, loquat) were covered with polyethylene-net bag. We investigated damage of guava and loquat by means of polyethylene-net bag method after grazing. After two times of each experiments used polyethylene-net bag were removed, and added two iron posts both sides of fruit tree. Wire-net was put tightly around four posts of tropical fruit tree. Grazing experiments of the wire-net bag method were conducted eight times from July to January in the following year. The mean ratio of damaged guava per day were shown 4.3% in polyethylene-net bag method and 1.6% in wire-net method. The mean ratio of damaged loquat per day in polyethylene-net bag method and wire-net method were shown 1.9% and 0.7% respectively. As we compared the ratio of damaged fruit tree in polyethylene-net bag method with wire-net method, its ratio was significant low in wire-net method, its ratio was significant low in wire-net method. But the ratio of damaged between guava and loquat were not significant. From the results described above, we found the wire-net method was more effective grazing protecton than the polyethylene-net bag method. 紀要論文 |
| Databáze: | OpenAIRE |
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