缺氮对叶用甘薯生长及生理的影响

以叶用型甘薯品种台农71和莆薯53为试验材料,研究了在水培条件下正常供氮、缺氮以及缺氮后恢复供氮3种处理对不同叶用甘薯生长和生理代谢的影响。结果表明:缺氮条件下,2个品种的藤蔓生长量下降,根系生长增加,叶绿素含量、叶片净光合作用、气孔导度和蒸腾速率均显著下降,叶和根的硝酸还原酶活性下降,而谷氨酰胺酶活性上升,大多数的必需氨基酸和非必需氨基酸含量均显著下降,且台农71品种的变化程度大于莆薯53品种;缺氮后恢复供氮,相应的指标均呈恢复趋势,其中各指标在莆薯53品种中均恢复到正常供氮水平,表明2个叶用型甘薯对氮素的敏感性不同,品种台农71对氮素的反应比品种莆薯53更敏感。

Effects of Nitrogen Deficiency on the Growth and Physiology of Leaf-vegetable Sweet Potato

Took the leaf-vegetable sweet potato Tainong 71 and Pushu 53 as experimental materials, the effects of normal nitrogen supply, nitrogen deficiency and nitrogen recovery on the growth and physiological metabolism of different sweet potato under hydroponic conditions were studied. The results showed that under the condition of nitrogen deficiency, 2 varieties of vine growth decreased, root growth increased, leaf chlorophyll content, net photosynthesis, stomatal conductance and transpiration rate decreased significantly, decreased the nitrate reductase activity in roots and leaves, and the transglutaminase activity increased, most of the non-essential amino acid and essential amino acid content decreased significantly, and the change degree of Tainong 71 more than Pushu 53. After the recovery from nitrogen deficiency, the corresponding index showed a recovery trend, the index in Pushu 53 varieties were restored to normal level. It was showed that the sensitivity of two leaf-vegetable sweet potatoes were different, Tainong 71 was more sensitive than variety Pushu 53 to nitrogen.