Ca^(2+)对高温强光胁迫下多花黄精抗逆生理和光合特性的影响  

Effects of calcium on stress-resistance physiology and photosynthesis of Polygonatum cyrtonema Hua under high temperature and strong light stress

作　　者：梁永富[1] 王康才[1] 隋利 薛启[1] 易家宁 LIANG Yong-fu;WANG Kang-cai;SUI Li;XUE Qi;YI Jia-ning(College of Horticulture,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学园艺学院,南京210095

出　　处：《生态学杂志》2018年第8期2345-2353,共9页Chinese Journal of Ecology

基　　金：江苏省林业三新工程项目(LYSX[2014]48)资助

摘　　要：通过分析不同Ca^(2+)浓度对高温强光胁迫下多花黄精光合作用及抗逆生理指标的影响,探讨外源Ca^(2+)缓解多花黄精高温强光胁迫伤害的可行性。以遮阴处理的盆栽多花黄精为材料,用改良的Hoagland溶液进行培养,培养液Ca^(2+)浓度分别为5、10、15、20、25mmol·L-1,在高温强光天气来临之前撤掉遮阴棚进行胁迫处理,胁迫处理10 d后测定多花黄精光合及生理等指标,待多花黄精倒苗后,测定其根茎产量和活性成分含量。实验设置常温25℃遮阴和高温强光胁迫下浇Hoagland溶液2个对照。结果表明,适宜浓度的Ca^(2+)处理可显著增强多花黄精SOD、POD和CAT酶活性,减少细胞中O2-·和H_2O_2含量,降低MDA含量和相对电导率,有效减轻了多花黄精的高温胁迫伤害。同时,Ca^(2+)处理还提高了叶绿素含量、气孔导度、可溶性蛋白和脯氨酸含量,并加快了光合电子传递,降低了NPQ,提高了多花黄精PSII实际光化学效率、ETR和qP,使多花黄精能够在高温强光胁迫下维持较高的净光合速率。但随着Ca^(2+)浓度的增加,多花黄精的抗逆性会降低。就本试验而言,10mmol·L-1的Ca^(2+)处理能显著降低多花黄精的高温强光胁迫伤害,提高其根茎收获量及活性成分含量。To understand whether exogenous calcium could alleviate damages in Polygonatum cyrtonema Hua caused by high temperature and strong light stresses, the effects of different Ca^2＋ concentrations on the photosynthesis and physiological indices of stressresistance of P. cyrtonema were assayed under high temperature and strong light environment. P. cyrtonema was cultivated in pots and irrigated with modified Hoagland’s solution with five Ca^2＋ concentrations （5, 10, 15, 20, 25 mmol·L^-1）. Stress treatments were started by exposing plants to high temperature and strong light, with photosynthesis and physiological parameters being measured ten days later. The biomass of roots and stems and the contents of active compounds were measured after P. cyrtonema were tumbled. There were two controls, with plants being irrigated with Hoagland’s solution and cultivated at 25 ℃/shade, as well as under high temperature and strong light. The results showed that proper Ca^2＋ concentration alleviated damages of high temperature stress by enhancing the activities of SOD and CAT, inhibiting hydrogen peroxide （H2O2） and superoxide anion radical （O2^-·） accumulation, and reducing malonaldehyde content and relative conductance. Furthermore, the addition of Ca^2＋ increased chlorophyll contents, stomatal conductance, proline and soluble protein contents, maximal photochemical efficiency of photosystem II （Fv/Fm）, effective quantum yield of photosystem II （Yield）, relative electron transport rate （ETR） and photochemical quenching index （qP） and decreased NPQ. The stressresistance of P. cyrtonema was declinedwith increasing Ca^2＋ concentration. In this study, Ca^2＋ concentration at 10 mmol·L^-1 alleviated stress damages in P. cyrtonema caused by high temperature and strong light and increased the yield and content of active compounds.

关 键 词：多花黄精 高温强光 生理指标 光合作用 

分 类 号：S567.239[农业科学—中草药栽培]