氮磷钾缺乏对香蕉幼苗生长及养分吸收的影响

Effects of Nitrogen,Phosphorus and Potassium Deficiency on Growth and Nutrient Absorption of Banana Seedlings

为探讨氮、磷、钾缺乏对香蕉幼苗生长及养分吸收与分配机制的影响,本研究以宝岛蕉幼苗为材料进行石英沙养分胁迫模拟培养试验。结果表明:养分胁迫使香蕉苗地下组织生物量增加,地上生物量减少,根冠比增大;香蕉苗光合作用受气孔及非气孔因素的共同影响,缺素对光合作用影响的排序为磷>钾>氮;各器官的养分含量及累积量大小依次为钾>氮>磷,需钾量最大;各器官养分需求量排序为叶>茎>根,叶是氮的主要积累器官,茎和叶是钾的主要积累器官;氮和钾之间存在协同作用,缺钾显著抑制氮向叶片运输,缺氮抑制钾向地上运输。研究结果为香蕉幼苗在养分胁迫环境下的营养诊断施肥提供了参考。

In order to investigate the effects of nitrogen,phosphorus and potassium deficiency on the growth and the mechanism of nutrient uptake and distribution of banana seedlings,this study used Baodao banana seedlings as materials to conduct a nutrient stress simulation culture experiment in quartz sand.The results showed that the underground biomass of banana seedlings increased,the aboveground biomass decreased,and the root-shoot ratio increased under nutrient stress.The photosynthesis of banana seedlings was affected by both stomatal and non-stomatal factors,and the order of the effect of nutrient deficiency on photosynthesis was phosphorus>potassium>nitrogen.The order of nutrient content and accumulation of each organ was potassium>nitrogen>phosphorus,and the potassium requirement was the largest.The order of nutrient requirement of each organ was leaf>stem>root.Leaf was the main accumulation organ of nitrogen,and stem and leaf were the main accumulation organ of potassium.There was a synergistic effect between nitrogen and potassium.Potassium deficiency significantly inhibited nitrogen transport to leaves,while nitrogen deficiency inhibited potassium transport to the ground.The results provide a reference for nutritional diagnosis and fertilization of banana seedlings under nutrient stress.