水田滿江紅 Azolla pinnata 研究－Ⅱ.土壤與肥料因子對滿江紅生長之影響

Abstract

本省常用化學肥料中，除硫銨ammonium sulfate 外，尿素urea 、臺肥複合肥料1 號及4 號Taiwan comound Fertializer No . 1 and No . 4 在N 54kg / ha 用量下都會殺死滿江紅。尿素在N 15kg/ha 及N 54kg / ha 用量下雖不殺死滿江紅，但仍明顯抑制其生長。不同陰離子型銨鹽中在N 45kg / ha 下，醋酸銨ammonium aceate、碳酸銨ammonium carbonate及檸檬酸銨ammonium citrate 對滿江紅都有致死作用，但是硝酸銨ammonium nitrate 及氯化銨ammonium chloride 有助滿江紅生長。 在培養液內，滿江紅之固氮活陸並不因溶液內氮濃度高低而有所不同。但土壤加水之水面上，滿江紅固氮受硫銨用量之影響甚大，在N 18kg / ha , N 36kg / ha 及N 54kg / ha 之用量下都明顯抑制了滿江紅的固氮作用，不過添加過磷酸石灰對滿江紅固氮力之恢復會有幫助。 在不施肥情況下，一般酸性土壤加水之水面上培養滿江紅之效果較鹼性土壤者為佳，施P2O5 15kg / ha 後情形亦同。酸性土壤中又以酸性粘板岩沖積土最能反應磷肥效應。水深亦影響磷肥效用。就滿江紅生長情形而言，磷肥表施後土壤表面上水深以3~5cm 為宜。 田間養殖時氮、磷、鉀三種要素中，以磷肥對滿江紅之效應最顯著。只要有磷肥之處理滿江紅產量都佳。不施用磷肥者產量低，且含氮量亦低。 At the rate of N 54kg/ha, urea, Taiwan compound fertilizer No. 1 and Taiwan compound fertilizer No. 4 killed the azolla, but ammonium sulfate did not. Low rates of urea, i. e. N 15 and N 5kg/ha, retarted the growth of the azolla. At the rate of N 45 kg/ha of ammonium acetate, ammonium carbonate and ammonium nitrate, the azolla was killed also, but ammonium chloride and ammonium nitrate were helpful for the growth of the azolla. The nitrogenase activity of the azolla was hardly influenced either by the high or the low concentrations of nitrate nitrogen in Tollen’s solution, but was seriously inhibited by the application of ammonium sulfate at the rates of N 18, N 36 and N 54 kg/ha. The addition of superphosphate was helpful for the recovery of azolla’s nitroge nase activity which was inhibited by ammonium sulfate application. With and without P addition, the azolla grew more vigoriously in acidic soilwater than in calcareous soil water. The soil water of acidic slate alluvial soil was found to be The most suitable for azolla growth, while the calcareolus slate alluvial soil water was found to be the most unsuitable one. Water depth around 3-5 cm were better than that of 1 cm for the superphosphate application. The N. P. K. fertility tests in field showed that the P had the dorminant effect among these three elments.