微波处理对Na_2CO_3胁迫下燕麦苗期氮代谢的影响

Effects of Microwave Treatment on the Nitrogen Metabolism of Oat Seedlings under Na_2CO_3 Stress

为探讨微波对燕麦种子处理及其Na_2CO_3胁迫下燕麦苗期蛋白质和核酸代谢的影响,以白燕7号燕麦品种为材料,采用2450 MHz频率下,不同功率及时间的微波对种子进行预处理,比较了不同处理对燕麦幼苗早期代谢和发育的影响,结果表明:低功率(36%)预处理对Na_2CO_3胁迫下单株干物质积累及株高和根长有明显的促进作用,诱导激活了叶片硝酸还原酶(NR)、谷氨酰胺合成酶(GS)的活性,抑制了蛋白水解酶和核糖核酸酶活性,增加了核酸和蛋白质的积累,降低叶片中游离氨基酸含量,其中,30 s处理组显著优于对照组(p<0.05);中等功率(58%)15 s处理仍具有正向调控作用,但随处理时间的增加抑制作用显现和增强。微波处理燕麦种子,可以在碱性盐逆境下,通过调控苗期氮代谢,促进碳流由光合碳代谢向氮代谢的转变,维持盐害下燕麦幼苗核酸和蛋白质代谢的正常进行,增强燕麦幼苗抵御Na_2CO_3胁迫的能力。

In order to explore the effects of microwave on oat seedling treatment and protein and nucleic acid metabolism of oat in seedlings stage under Na2CO3 stress, the influence of Bai Yan 7 oat seedling early metabolism and development under different power and time of microwave pretreatment using 2450 MHz is compared. The results show that low power （36%） pretreatment of Na2CO3 stress obviously promotes dry matter accumulation ,plant height and root length in single plant, which induce the NR and GS activity, suppress the activity of proteinase and RNase and increase the nucleic acid and protein accumulation. The pretreatment also reduces the free amino acid content in the leaves. Among them, 30 s treatment group is significantly better than the control group （p〈 0.05） ; Medium power （58%）, 15 seconds have positive regulation effect, but with the increase of the processing time visions inhibition emerged and enhanced. Under alkalic salt stress, through the regulation of nitrogen metabolism, microwave treatment promote the transformation of carbon from photosynthetic carbon metabolism to nitrogen metabolism , maintain the normal metabolism of nucleic acid and protein under salt stress and enhance the resisting ability of oat seedlings to Na2CO3 stress.