NO在CO2激光预处理提高小麦耐旱性中的作用

Effect of NO on CO_2 Laser Pretreatment Inducing Drought Tolerance in Wheat Seedlings

用CO2激光(20.1 mW/mm2)辐照小麦种子3 min,待其长至12天时,用质量浓度10%聚乙二醇6000(PEG6000)胁迫其幼苗,并通过添加NO的供体硝普钠(SNP)和血红蛋白(Hemoglobin,Hb;NO清除剂),研究NO在CO2激光预处理提高小麦耐旱性中的作用。结果表明,外源NO和激光预处理可使干旱胁迫的小麦幼苗丙二醛(MDA)含量显著降低(p<0.05),而超氧化物歧化酶(SOD),过氧化物酶(POD),过氧化氢酶(CAT)活性,叶绿素a,叶绿素b含量和根干重却显著增加(p<0.05)。而经过适当剂量激光辐照干旱胁迫小麦幼苗再加外源血红蛋白(Hb,NO清除剂)处理则没有这种作用。

The wheat seeds are irridated by CO2 laser with power of 20. 1 mW/mm^2 for 3 min. When the wheat seeds grow about 12 days, the seedlings are treated with the 10% polyethyleneglycol 6000 （PEG6000） stress. And the effects of NO on the CO2 laser pretreatment inducing drought tolerance are studied through sodium nitroprusside and hemoglobin added with NO. The results show that laser pretreatment and NO donor sodium nitroprusside （SNP） could decrease the concentration of malondialdehyde （MDA） and increase the activities of superoxide dismutase （SOD）, peroxidase（POD）, catalase （CAT） and the concentration of chlorophyll a, chlorophyll b and root dry weight in the wheat seedlings with drought tolerance. But the promotive effect of laser pretreatment induced drought tolerance in wheat seedlings was not effectively reversed by the addition of hemoglobin （NO scavenger）.