低温胁迫下玉米幼苗根系受外源海藻糖调控的生理表现  

Physiological manifestations of maize seedling roots regulated by exogenous trehalose under low temperature stress

作　　者：刘旋[1] 田礼欣 佟昊阳[1] 左师宇[1] 李晶[1] LIU Xuan;TIAN Li-xin;TONG Hao-yang;ZUO Shi-yu;LI Jing(College of Agronomy,Northeast Agricultural University,Harbin 150030,China）.)

机构地区：[1]东北农业大学农学院,哈尔滨150030

出　　处：《生态学杂志》2018年第8期2354-2361,共8页Chinese Journal of Ecology

基　　金：东北春玉米减灾保产调控关键技术研究(2017YFD0300405)资助

摘　　要：为了探究海藻糖对增强玉米幼苗抗低温能力的生理表现,以玉米"先玉335"为试验材料,采用盆栽试验,分析12 mmol·L-1外源海藻糖对低温胁迫不同时间(0、2、4、6和8d)下玉米幼苗根系生物量、抗氧化酶活性及渗透调节物质的影响。结果表明:低温胁迫显著抑制玉米幼苗根系生长及干物质累积,诱导抗氧化酶活性增加,破坏细胞渗透调节水平;低温胁迫后应用外源海藻糖,玉米幼苗根系根表面积、根长及鲜干重显著增加,根系内SOD、POD和CAT活性呈现先升高后降低趋势,MDA含量及相对电导率在玉米幼苗根系内显著降低,脯氨酸、可溶性蛋白、可溶性糖含量也呈现先升高后降低趋势;在低温胁迫第6天时,T+L处理的根系根表面积、根长及鲜干重分别较CK+L增加了18.25%、4.73%、2.48%和21.43%;T+L处理后根系内SOD、POD和CAT活性分别较CK+L处理提升17.26%、23.79%和30.78%;T+L处理后根系内MDA含量和相对电导率值分别较CK+L处理降低45.13%和63.25%;T+L处理后的脯氨酸、可溶性蛋白和可溶性糖含量在低温胁迫第6天时最高,与CK+L处理相比差异显著,且分别较CK+L高出2.93、0.51和2.58倍。可见,海藻糖能够调控低温胁迫下玉米幼苗根系生理水平,提高玉米幼苗抗逆能力,促进玉米根系生长及生物量增加,海藻糖对作物生长的生理调控能力与低温存在协同作用,在低温环境下,海藻糖对作物体内抗氧化系统酶活表达及渗透物质的积累有显著提升效果。To investigate the physiological properties of maize seedlings in enhancing the chilling resistance under exogenous trehalose, a pot experiment was carried out with ‘Xianyu 335’. The effects of 12 mmol·L^-1 exogenous trehalose on root biomass, antioxidant enzyme activities and osmotic adjustment substances of maize seedlings at different chilling temperatures （0, 2, 4, 6 and 8 d） were examined. The results showed that chilling stress significantly inhibited root growth and dry matter accumulation of maize seedlings, increased antioxidant enzyme activity, and destroyed the level of osmotic regulation. In response to trehalose application, root surface area, root length and fresh dry weight of maize seedling significantly increased, activities of SOD, POD and CAT in roots first increased and then decreased, MDA content and relative conductivity in roots significantly reduced. The contents of proline, soluble protein and soluble sugar in the roots were also increased first and then decreased. Compared with the CK＋L treatment at the 6th day of chilling treatment, the root surface area, root length and dry weight under the treatment of T＋L increased by 18.25%, 4.73%, 2.48% and 21.43%, respectively. The activities of SOD, POD and CAT significantly increased by 17.26%, 23.79% and 30.78%, respectively. The MDA content and relative conductivity significantly decreased by 45.13% and 63.25%, respectively. The contents of proline, soluble protein and soluble sugar in T＋L treatment were the highest at the 6th day after chilling stress, being 2.93, 0.51 and 2.58 times higher than that under CK＋L treatment, respectively. It is concluded that trehalose can regulate the physiological level of roots of maize seedlings under chilling stress, improve the ability of stress resistance of maize seedlings, and accelerate root growth. Trehalose has a synergistic effect on the physiological regulation of crop growth under low temperature stress. At chilling environment, trehalose can significantly enhance the expression o

关 键 词：玉米 海藻糖 低温胁迫 抗氧化酶系统 渗透调节物质 

分 类 号：S513[农业科学—作物学]