@article{oai:u-ryukyu.repo.nii.ac.jp:02002913, author = {新城, 健 and 星野, 正生 and Shinjo, Takeshi and Hoshino, Masao}, issue = {36}, journal = {琉球大学農学部学術報告, The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus}, month = {Dec}, note = {南西諸島における熱帯イネ科牧草の適草種・品種を選定するために有望と思われる熱帯イネ科牧草の5草種(ローズグラス, ギニアグラス, グリーンパニック, セタリア, バッフェル)の乾物生産性と季節生産性について比較検討した。その結果, 年間の乾物生産量は5草種のなかで, セタリアが最も大きく10a当り2230kg, 以下, ローズグラス1790kg, ギニアグラス1690kg, グリーンパニック1590kg, バッフェル1410kgであった。セタリアとギニアグラスは株がよく分けつして植生密度の高い安定した草地を形成した。両草種は永続性も認められ, 南西諸島における永年草地の牧草として主要な役割を果すものと考えられた。ローズグラスは初期生育が極めて良く, 1年目の乾物収量は最も高くなったが, 試験期間の後半になると枯死株を生じて植生密度が低くなり, 4年目の乾物収量は5草種のなかで4番目に低下した。このことからローズグラスは永年草地における草種としては永続性に問題があると考えられた。グリーンパニックとバッフェルは株の分けつも少なく, 栽培が長期間になると枯死株が多数発生して植生密度が低下し, 雑草の侵入を容易に許すなど, 草地の衰退が顕著であった。供試した5草種の生産性の季節変化は大きく, 5月から9月までの生育条件の良い高温時に生産が促進され, 逆に低温時の10月から2月には著しく停滞した。季節生産性の最も大きい6月の1日当りの5草種平均の乾物生産量はm^2当り9.27gであったが, 最少の2月は2.13gで, 6月の乾物生産量の1/4以下であった。, The work reported here was designed to compare the productivity of dry matter, and trend of seasonal yield of five tropical pasture grasses (Guinea grass, Rhodes grass, Green panic grass, Setaria and Buffel grass) in the South-Western Islands of Japan. Throughout the whole period of experiment Setaria showed the highest dry matter yield in a year, namely (2,230kg/10a) followed by Rhodes grass (1,790kg/10a), Guinea grass (1,690kg/10a), Green panic (1,590kg/10a) and Buffel grass (1,410kg/10a). Setaria and Guinea grass being bunch type grasses develop continuously a number of tillers and form a dense and stable pastures. As these grasses are persistent and tolerate to frequent cuttings, it is considered that as a constituent of permanent pastures, these two grasses seemed to be the most prommising tropical grasses in the South-Western Islands of Japan. In the early stage of this experiment, the growth of Rhodes grass were vigorous. In the first year of experiment, dry matter yeild of Rhodes grass showed the highest of all species. But in the late stage of experiment, it was shown that many plants died and the plant density was decreased sharply. In the fourth year, there was marked reduction in the dry matter yield, Rhodes grass showed the fourth producer of five species. As a constituent of permanent pastures, Rhodes grass showed a lack of persistency. Green panic grass and Buffel grass showed low ability of tillering, and in the late stage of experiment, as was shown in the Rhodes grass, there were shown dead stubbles and invasion of weeds showing the deterioration of pasture sward. Dry matter yield of five grasses showed marked seasonal changes. Between May and September, the growth were rapid and yield were high level, and during low temperature season (Oct.-Feb.), a marked reduction of dry matter yield was observed. Average dry matter yield per m^2 per day of five grasses was 9.27g in June, in February it was 2.13g. Dry matter yield in February was less than one fourth of June., 紀要論文}, pages = {131--136}, title = {南西諸島における熱帯イネ科牧草の導入と栽培 (I) : 有望 5 草種の比較について(農学部付属熱帯農学研究施設)}, year = {1989} }