低氧胁迫对樱桃根系呼吸功能及氮代谢的影响

EFFECTS OF HYPOXIA ON THE ROOT ACTIVITY,RESPIRATORY RATE AND THE NITROGEN METABOLISM IN ROOTS OF CHERRY

以樱桃组培苗'吉塞拉5号'为试材,采用控制营养液溶氧浓度的方法,研究了低氧胁迫对其幼苗根系活力、根系呼吸速率以及氮代谢的影响。结果表明:低氧处理诱导樱桃根系活力升高,抑制根系的呼吸速率且初生根受到的抑制作用更强,但随着胁迫时间的延长,低氧胁迫的这种影响作用逐渐降低。低氧胁迫诱导了硝酸还原酶(NR)和谷氨酰胺合酶(GS)的活性。而对谷氨酸脱氢酶(NADH-GDH)的活性先抑制后促进之后又抑制。处理结束时可溶性蛋白含量降低,脯氨酸含量升高。说明樱桃可通过增加呼吸消耗、改变代谢途径来缓解低氧逆境伤害。

The method of controlling dissolved oxygen concentration in nutrient solution was used.Effects of hypoxia on root activity,respiratory rate and nitrogen metabolism in the cherry rootstock roots were studied.Results showed that the root activity was increased,the respiratory rate of primary roots was more inhibited than transport roots′.But the effects were decreased with the treatment time.The activity of nitrate reductase(NR) and glutamine synthethase(GS) was improved under hypoxia.The activity of glutamate dehydrogenase(NADH-GDH) was inhibited first and then was promoted,was decreased at last.At the end of treatment,soluble protein content was decreased and proline content was increased.The effects of hypoxia stress were reduced probably by improving respiration consumption and changing the metabolic pathway.