穿龙薯蓣氮、磷、钾缺素症状研究

用砂培法,以盆栽穿龙薯蓣的根状茎为试材,对氮、磷、钾缺素症状进行了研究。结果表明:3种元素缺乏时均是下部老叶先表现出症状,且开花结实不正常,花少、果少、果枝短。缺氮时,老叶叶肉失绿,出现黄褐色病斑,严重时叶片全缘黄化焦枯,植株矮小,叶片小,分枝少,根茎萌芽少。缺磷时,老叶叶尖干枯或叶脉失绿后扩散到叶肉,叶片黄色、枯黄色和淡黄色错落出现呈“花叶”,后期叶色深绿。缺钾时,叶尖焦枯或叶缘随机分布褐色斑点,进而叶缘全焦枯,叶肉黄化,而叶基部保持绿色,全株叶片较稀疏,萌发的新根少。

Research on Nitrogen, Phosphorus and Potassium Deficiency of Dioscorea nipponica

Using rooty stem as reproduce material,the N,P and K deficiency of Dioscorea nipponica was studied with sandy culture.The result indicated that in lack of the three elements,the underside of the plant first showed symptoms,the florescence burliness was abnormal,the flower and fruit were low in amount,and the branch was short.In lack of N,the old leaf at the bottom of the plant showed chlorosis,and tan spot on the tip or in the middle of the leaf,and the edge of the leaf burnt and faded;Other symptoms are nanism,lack of fruit and leaf,and no or small flourishing;Growth of procreate was influenced,florescence was delayed,fruit and bud in root and stem were low in amount.In lack of phosphorus,the tip of the old leaf was dry and dull or chlorosis in the leaf vain,the old leaf became deep green when the lack of the element was serious;Chlorosis extended to blade,and appeared yellow,scorch and light green.In lack of potassium,the old leaf showed symptoms first.The tip of the leaf was dry and faded or brown spot distributed randomly on the edge of the leaf,then the edge of the leaf was dry and faded,the blade was etiolated,but the radical part kept green;the female flower varied,and inflorescence was short and lack of male flower,premature senility;the leaf was scarce,and the top of the plant was lower in amount;there was fewer fiber or new root,and it aggregated.