【作者】 刘子会；

【导师】 李广敏； 王刚； 郭秀林；

【作者基本信息】 河北师范大学 ， 植物学， 2004， 硕士

【摘要】 本试验以玉米（Zea mays）郑单958为材料，通过外源ABA溶液、pH溶液、EGTA、Verapamil和TFP处理，研究了干旱胁迫条件下玉米不同器官及其木质部汁液ABA浓度和pH及气孔导度和蒸腾速率的响应规律，试验结果如下： 1．干旱胁迫对玉米不同器官及其木质部ABA含量，木质部汁液pH及气孔导度和蒸腾速率的影响试验表明：干旱胁迫下，根系首先合成ABA；干旱初期叶片ABA总量保持不变，但植物通过提高木质部汁液pH，改变ABA在叶组织间的重新分布，从而提高本质部汁液ABA浓度，降低气孔导度和蒸腾速率。 2．100μmol／L外源ABA溶液和干旱胁迫共同处理，并未提高玉米幼苗叶、茎、根ABA总量，但提高了木质部汁液ABA浓度和pH，减小了气孔导度，降低了蒸腾速率。这充分表明：玉米气孔导度和蒸腾速率主要受木质部汁液ABA浓度调控。 3．不同pH外源溶液处理使得叶片木质部汁液pH升高，叶片ABA总量及木质部ABA浓度都表现从pH5到pH8逐步增加的趋势，而气孔导度和蒸腾速率都降低。这充分表明：pH能够通过改变叶片尤其是木质部ABA含量，从而影响气孔导度和蒸腾速率。不同pH溶液和ABA溶液联合作用进一步表明：碱性环境中更有利于ABA在植株体内累积。 4．2 mmol／L EGTA和干旱胁迫处理使得玉米叶、茎、根的ABA总量降低，但提高了本质部汁液ABA浓度和pH，部分降低了气孔导度和蒸腾速率；100μmol／L异博啶和干旱胁迫处理得到类似结果，这表明：Ca²⁺参与了干旱胁迫下玉米幼苗ABA的合成过程。 5．80μmol／L TFP和干旱胁迫处理使得玉米根系ABA含量提高，叶片、根系木质部汁液pH和叶片木质都汁液ABA浓度升高，但降低了气孔导度和蒸腾速率。结果表明：CaM可能未参与玉米幼苗ABA的合成及其信号转导过程。更多还原

【Abstract】 The drought signal molelular and its relation with Ca2+/CaM system under drought stress were studied with exogenous ABA.pH and EGTA,verapamil,TFP in this paper.The results were as follows:1 The effects of drought stress on total ABA contents of different tissues,[ABAxyl] and pH of xylem sap,stomatal conductance and transpiration rate of maize seedlings showed that ABA was firstly synthesized by roots during drought stress.At the preliminary time of treatment, total ABA contents of the leaves were not changed ,but [ABAxyl]L increased. This were perhaps induced by increase of pH value of the xylem sap. As a result, the stomatal conductance and transpiration rate decreased.2 when maize seedlings were treated with both 100 mol/L exogenous ABA solution and drought stress.ABA bulk contents of maize seedlings did not increase, but [ABAxyl] and pH of the xylem sap were increased .stomatal conductance were decreased. The results showed that stomatal conductance was mainly controlled by ABA concentration of xylem sap.3 Both ABA contents of the leaves and [ABAxyl]L increased with the increase of exogenous pH buffer from 5 to 8, and pH value of xylem sap was raised when the maize were treated by pH buffer. At the same time , the stomatal conductance and transpiration rate decreased . The results verified the view that it is through modifying xylem sap ABA concentration that pH has effect on the stomatal conductance and transpiration rate. The studies of pH buffer and ABA suggested that ABA were accumulated easily in the alkaline circumstance.4 Hie total ABA contents of leaves decreased, but ABA concentration and pH of the xylem sap increased when the maize were treated by 2 mmol/L EGTA solution. Accordingly, the stomatal conductance decreased. The effects of 100 mol/L verapamil on maize seedlings were similar to that of EGTA. The results revealed that Ca2+participated in ABA synthesis process.5 ABA contents of the roots, pH of the xylem sap of leaves and roots ,and ABA concentration of the leaves xylem sap all increased when the maize were treated by 80 mol/L TFP solution. As a result, the stomatal conductance decreased . This showed that CaM may not participated in ABA synthesis and ABA signal transduction.更多还原