@article{oai:u-ryukyu.repo.nii.ac.jp:02003065, author = {宮城, 悦生 and Miyagi, Etsuo}, issue = {29}, 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 = {窒素施用がグリーンパニックの生産におよぼす影響を検討するため, 窒素施用量年間10a当り15kg, 30kg, 60kgおよび90kgの試験区を設定し, 1980年および1981年の2年間栽培試験を実施した。1.生草収量は1980年および1981年ともに年間10a当り窒素施用量60kg以上で22.5t以上が得られた。同様に乾物収量についても4.3t以上が得られた。2.茎数, 出穂茎数および茎重は窒素施用量の増量にともなって増加し, 試験区間に有意差が認められた。3.草丈および平均葉数は窒素施用量の増量にともなって増加したが, 葉重比は逆に減少傾向を示し, 試験区間に有意差が認められた。4.葉面積指数(LAI)も窒素施用量の増量にともなって増加し, 60kg以上で各番草とも6.0以上のLAIを示した。以上の結果からグリーンパニックの生産に対する窒素施用量は年間10a当り60kgが適当と考えられる。なお, 窒素施用の効果は茎数に大きな変化をもたらすとともに平均葉数にも効果をもたらし, LAIの増加を促すことにより, グリーンパニックの生長速度を促進し, その結果, 乾物収量に効果をもたらすものと考えられる。, A field experiment was conducted to investigate the effect of nitrogen on the yields of green panic. The grass was grown for two years from 1980 to 1981 on the dark red soil, which is one of the typical soil derived from limestone,Maagiin Okinawa. Nitrogen at four levels of 15,30,60 and 90kg per 10 are per year was applied. The results are summerized as follows : 1) It showed a marked increase in the yield with increasing rate of nitrogen up to 60kg in either year. Little difference was observed between the two levels of nitrogen, 60 and 90kg. Fresh and dry yield of the grass receiving more than 60kg nitrogen per year were more than 22.5 and 4.3 tons, respectively. 2) The application of different rates of nitrogen improved the number of tillers and heading tillers and the weight per tiller. The grass length and the number of leaves per tiller increased at a rise in nitrogen while the leaf weight ratio decreased against the amount of nitrogen. 3) With increasing rate of nitrogen the leaf area index (LAI) rised. The value was more than 6 at each cutting on the plots both of 60 and 90kg. From these results the most optimum amount of nitrogen was seemed to around 60kg per 10 are per year to obtain higher yield of green panic onMaagisoil., 紀要論文}, pages = {193--198}, title = {1. 窒素施用がグリーンパニック (Panicum maximum var. trichogtume) の生産におよぼす影響(暖地型牧草の生産性および飼料価値に関する研究)(畜産学科)}, year = {1982} }