摘要
为探究甘薯对干旱胁迫的应答机制及其生长需水规律,以‘商薯19’为供试材料,通过无土栽培方式,研究不同干旱强度(PEG-6000浓度分别为0%、6%、12%、18%、24%)对甘薯活性氧代谢、渗透调节物质、SPAD及叶绿素荧光特性的影响。结果表明,随着干旱胁迫强度的增加,保护酶SOD、POD、CAT、APX活性,可溶性蛋白质和可溶性糖含量均呈现先升高再降低的变化规律,且PEG-6000浓度不高于7%可诱导叶片保护酶SOD、POD、CAT和APX活性的提高。可溶性蛋白质和可溶性糖含量在PEG-6000浓度7%时值最大,较对照分别增加58.09%和161.14%。脯氨酸和丙二醛含量随干旱胁迫强度的增强而逐渐增加。PEG-6000浓度不高于3%能够刺激甘薯叶片叶绿素的生成。SPAD与干旱胁迫强度有极显著的负相关关系,两者的拟合方程y=54.354e-3.323x。初始荧光(Fo)表现出先降低再升高的变化规律,在PEG-6000浓度3%时值最低;最大荧光(Fm)、最大光化学效率(Fv/Fm)和光化学猝灭系数(qP)随干旱胁迫强度的增加表现出先升高再降低的单峰变化规律,且在PEG-6000浓度3%时值最大,与初始荧光(Fo)具有负相关关系。研究得出,土壤含水量保持在PEG-6000浓度3%,可以使甘薯幼苗保持健壮生长,实现节水灌溉,但土壤干旱强度不能超过PEG-6000浓度的7%,否则会对甘薯苗期形态特征和生理特性造成不利影响。
To explore the response mechanism of sweet potato to drought stress and its growth water requirement,the effects of different drought intensities(0%,6%,12%,18%and 24%of PEG6000 concentration respectively)on active oxygen metabolism,osmotic regulators,SPAD and chlorophyll fluorescence characteristics of sweet potato were studied by soilless cultivation with‘Shangshu 19’as experimental material.The results showed that the activities of protective enzymes SOD,POD,CAT,APX,soluble protein and soluble sugar first increased and then decreased with the increase of drought stress intensity,and the activities of protective enzymes SOD,POD,CAT and APX increased when the concentration of PEG-6000 was not higher than 7%.The content of soluble protein and soluble sugar increased by 58.09%and 161.14%respectively when the concentration of PEG-6000 was 7%.The content of proline and malondialdehyde increased with the increase of drought stress intensity.When the concentration of PEG-6000 was not higher than 3%,it could stimulate the chlorophyll production of sweet potato leaves.SPAD was negatively correlated with the intensity of drought stress.The fitting equation of SPAD and drought stress was y=54.354 e-3.323 x.Initial fluorescence(Fo)showed the change rule of first decreasing and then increasing,and the lowest value was at 3%PEG-6000 concentration;the maximum fluorescence(Fm),maximum photochemical efficiency(Fv/Fm)and photochemical extinction coefficient(qP)showed a single peak change rule of first increasing and then decreasing with the increase of drought stress intensity,and the maximum value was at 3%PEG-6000 concentration,which had a negative correlation with initial fluorescence(Fo).It is concluded that water-saving irrigation could be achieved under the condition of maintaining healthy growth of sweet potato seedlings when the soil moisture content is kept at 3%PEG-6000 concentration,but the soil drought intensity could not exceed 7%of PEG-6000 concentration,otherwise,the morphological and physiological characterist
作者
储凤丽
刘亚军
王文静
胡启国
杨爱梅
Chu Fengli;Liu Yajun;Wang Wenjing;Hu Qiguo;Yang Aimei(Shangqiu Academy of Agricultural and Forestry Sciences,Shangqiu Henan 476000)
出处
《中国农学通报》
2019年第26期29-34,共6页
Chinese Agricultural Science Bulletin
基金
国家现代农业甘薯体系建设项目“国家甘薯产业技术体系商丘综合试验站(nycytx-16-C-5)
关键词
干旱胁迫
甘薯
活性氧代谢
渗透调节
叶绿素荧光
drought stress
sweet potato
active oxygen metabolism
osmotic regulation
chlorophyll fluorescence
