CAJ | 학술논문

在常温下用不同浓度的外源H2O2(0～20 mmol·L-1)预处理水稻幼苗,再进行12 h 6℃低温胁迫,根据幼苗相对含水量和质膜相对透性筛选最佳外源H2O2处理浓度,并分析最佳外源H2O2浓度下幼苗的渗透调节物质和活性氧相关指标的变化.结果表明:(1)0～8 mmol·L-1 H2O2预处理可以增加水稻幼苗的相对含水量,降低其质膜相对透性,并以4 mmol·L-1 H2O2的效果最佳.(2)低温胁迫后,与对照组相比,4 mmol·L-1外源H2O2预处理降低了水稻幼苗萎蔫程度,并使其总呼吸速率、交替途径容量都有增加,同时还抑制了丙二醛的含量,增加了可溶性糖、可溶性蛋白质和脯氨酸的含量.(3)外源H2O2预处理对水稻幼苗的内源H2O2含量以及O(-)/(·)2产生速率没有显著影响.研究发现,外源H2O2可以通过提高呼吸速率、降低脂质过氧化程度、增加碳氮代谢来有效增强水稻幼苗的抗寒性,它可能以一种独立于内源活性氧系统之外的方式发挥作用.
재상온하용불동농도적외원H2O2(0～20 mmol·L-1)예처리수도유묘,재진행12 h 6℃저온협박,근거유묘상대함수량화질막상대투성사선최가외원H2O2처리농도,병분석최가외원H2O2농도하유묘적삼투조절물질화활성양상관지표적변화.결과표명:(1)0～8 mmol·L-1 H2O2예처리가이증가수도유묘적상대함수량,강저기질막상대투성,병이4 mmol·L-1 H2O2적효과최가.(2)저온협박후,여대조조상비,4 mmol·L-1외원H2O2예처리강저료수도유묘위언정도,병사기총호흡속솔、교체도경용량도유증가,동시환억제료병이철적함량,증가료가용성당、가용성단백질화포안산적함량.(3)외원H2O2예처리대수도유묘적내원H2O2함량이급O(-)/(·)2산생속솔몰유현저영향.연구발현,외원H2O2가이통과제고호흡속솔、강저지질과양화정도、증가탄담대사래유효증강수도유묘적항한성,타가능이일충독립우내원활성양계통지외적방식발휘작용.
After 12 h of chilling stress at 6℃,pretreatment with H2O2 0～20 mmol·L-1 as foliar spray under normal growth conditions was measured.The results indicated that 0～8 mmol·L-1 H2O2 could significantly enhance relative water content (RWC) and decrease relative membrane penetration.The obvious effect of H2O2 occurred at 4 mmol·L-1.After chilling stress,compared with water-treated seedlings (contro1),4 mmol·L-1 H2O2 pretreatment relieved the wilting degree,increased total respiration rate (Vt),capacity of alternative pathway (Valt),inhibited the malonaldehyde (MDA) content and increased the soluble sugar content,soluble protein content and proline content.However,pretreatment of rice plants with 4 mmol·L-1 H2O2 showed no obvious effect on endogenous H2O2 content and the generating rate of O(-)/(·)2.These results suggest that the exogenous H2O2 could enhance rice seedlings chilling tolerance by enhancing respiration rate,the metabolism of carbohydrate and nitrogen and decreasing lipid peroxidation.The exogenous H2O2 was independent with the endogenous reactive oxygen species (ROS) pool in a certain way.