旱-盐复合胁迫对玉米种子萌发和生理特性的影响  

Effects of combined drought and salinity stress on germination and physiological characteristics of maize( Zea mays )

作　　者：姚海梅 李永生[1] 张同祯 赵娟[1] 王婵[1] 王汉宁[1] 方永丰[1] 

机构地区：[1]甘肃农业大学农学院/甘肃省作物遗传改良与种质创新重点实验室/甘肃省干旱生境作物学重点实验室,兰州730070

出　　处：《应用生态学报》2016年第7期2301-2307,共7页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展计划前期研究专项(2012CB722902);甘肃省财政厅科研业务费(035041046);甘肃省干旱生境作物学重点实验室开放基金(GSCS-2012-10)资助~~

摘　　要：分别用15%PEG、100 mmol·L^(-1)NaCl及其混合溶液模拟干旱(D)、盐(S)及旱-盐复合胁迫(D+S)对玉米种子萌发及幼苗生长的影响.结果表明:3种胁迫处理均明显抑制了种子萌发、幼芽、幼根的伸长及生物量的积累,且影响程度为D>D+S>S;幼芽及幼根中过氧化氢(H_2O_2)、超氧阴离子(O_2^(-·))等活性氧含量及丙二醛(MDA)含量明显升高,质膜相对透性增大,脯氨酸、可溶性糖和可溶性蛋白等生理渗透调节物质含量显著增加,且幼芽中含量高于幼根,积累程度均为D>D+S>S.3种胁迫处理均使幼芽、幼根中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)及抗坏血酸过氧化物酶(APX)等抗氧化酶活性增强;其中,SOD和APX活性表现为复合胁迫介于单一胁迫之间,而POD和CAT活性表现为复合胁迫大于单一胁迫;说明旱-盐复合逆境胁迫对玉米种子萌发及幼苗生理特性的影响并不是单一胁迫的简单叠加,与单一干旱胁迫相比,旱-盐复合胁迫在一定程度上能够缓解干旱胁迫对玉米种子萌发及幼苗生长的影响.In this study, 15% PEG, 100 mmol · L-1 NaCl and PEG-NaCl mixed solution were em- ployed to respectively simulate the drought （D）, salinity （S） and the combined stress （D＋S）, and effects of these three stresses on the seed germination and the physiological characteristics of seed- lings were investigated. The results showed that seed germination, seedling growth and biomass ac- cumulation were significantly inhibited by these three stresses, and the impact of stress ranked as D〉D＋S〉S. The content of reactive oxygen species like H202 and O2, as well as malondialdehyde （MDA） and membrane permeability were increased under these stresses, meanwhile, proline （Pro）, soluble sugar and soluble proteins contents were significantly improved, which were higher in seedlings than in roots with a rank of D〉D＋S〉S. The activities of antioxidant enzymes such as su- peroxide dismutase （SOD）, peroxide （POD）, catalase （CAT） and ascorbate peroxide （APX） were also obviously increased. In addition, SOD and APX induced by PEG-NaCl mixed solution were ranked in the middle compared to those induced by their single stress, but POD and CAT were more induced by PEG-NaCl mixed solution than their single stress. It was demonstrated that effect of drought-salinity combined adverse condition on maize seed germination and seedlings characteristics were not simply additive of their single stress, compared with their drought-salinity combined adverse condition could reduce the effects of drought stress physiological single stress, on maize see-ding to a certain extent.

关 键 词：玉米 复合胁迫 种子萌发 生理特性 

分 类 号：S513[农业科学—作物学]