外源钙缓解花生亚低磷光合障碍的机制  

Exogenous calcium alleviates phosphorus deficiency-induced photosynthetic inhibition in peanut(Arachis hypogaea)

作　　者：孙志宇 刘欣悦 张思威 马明珠 白蕊 刘欢 易伯涛 韩晓日[1] 刘轶飞[1] SUN Zhi-yu;LIU Xin-yue;ZHANG Si-wei;MA Ming-zhu;BAI Rui;LIU Huan;YI Bo-tao;HAN Xiao-ri;LIU Yi-fei(College of Land and Environment,Shenyang Agricultural University/National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources,Shenyang,Liaoning 110866,China)

机构地区：[1]沈阳农业大学土地与环境学院/土肥高效利用国家工程研究中心,辽宁沈阳110866

出　　处：《植物营养与肥料学报》2022年第6期1055-1066,共12页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金(31772391,31301842);中澳ARC-Linkage国际合作项目(LP200100341);辽宁省高校科研面上(青年)项目(LJKZ0661);国家花生产业技术体系岗位科学家项目(CARS-13)。

摘　　要：【目的】亚低磷胁迫是制约我国花生优质高产的一个重要因素,而外源钙可有效改善中低产田花生的生长发育和产量。为此,研究了外源钙缓解花生亚低磷光合障碍的机制。【方法】以我国东北花生主栽品种之一‘辽宁白沙’为试验材料,以Hoagland营养液为基础,在人工气候室内进行了砂培试验。花生幼苗催芽两周后进行处理,共设4个处理:1) CK,正常磷营养液(P 1 mmol/L)+喷清水对照;2)–P,亚低磷胁迫(P 0.5mmol/L)+喷清水;3)–P+Ca,亚低磷胁迫+叶面喷施CaCl_(2) 15 mmol/L;4)–P+TFP,亚低磷胁迫+钙调蛋白CaM抑制剂—三氟啦嗪(trifluoperazine,TFP)。处理后第9天,测定花生功能叶片气体交换、光系统活性;第10天,取样分析幼苗生长状况和类囊体膜完整性。【结果】亚低磷胁迫显著降低了花生的干物质积累、总叶面积和相对叶绿素含量,降低了花生叶片净光合速率P n、蒸腾速率Tr和气孔导度Gs;亚低磷胁迫显著降低了花生叶片PSⅡ实际量子产量Y(Ⅱ)、PSⅠ实际量子产量Y(Ⅰ)。与–P处理相比,–P+Ca处理显著提升了花生植株干物质积累和总叶面积,分别提高了26.7%和31.9%;改善了花生叶片的光合作用水平,显著提高了叶片净光合速率和气孔导度;外源钙提高了Y(Ⅰ)、Y(Ⅱ),明显缓解了亚低磷诱导的花生叶片Y(Ⅰ)和Y(Ⅱ)下降,提升了PQ库大小和环式电子传递,显著提高了类囊体ATP合酶活性,降低了类囊体的?pH,缓解了类囊体腔酸化。与–P处理相比,–P+TFP处理加剧了花生类囊体膜的损伤,并进一步降低了环式电子传递速率和ATP合酶活性。【结论】亚低磷胁迫显著限制花生的生长发育,降低了ATP合酶活性,造成了花生光抑制。外源钙能有效缓解亚低磷胁迫诱导的花生植株干物质积累、叶面积和相对叶绿素含量下降,并缓解亚低磷胁迫对光系统Ⅰ和光系统Ⅱ的抑制,而花生钙调蛋白(Ca^(2+)-modulin)作为钙离�【Objectives】The phosphorus(P) deficiency is one of the main factors limiting photosynthetic carbon fixation and high-quality yield in peanut production.Calcium can enhance peanut growth and yield in low to medium yielding farmlands.Therefore,we explored the effects of exogenous calcium on alleviating P deficiency-induced photosynthetic inhibition in peanuts.【Methods】Peanut cultivar ‘Liaoning Baisha’ was used in a pot experiment conducted in an artificial climate chamber.The P deficiency treatment was imposed by adjusting the P concentration in Hoagland nutrition solution to 0.5 mmol/L(–P) from the normal level of 1 P mmol/L.The treatments were normal P + spraying ddH_(2)O(CK),–P + spraying ddH_(2)O,–P + spraying CaCl_(2),and –P + spraying trifluoperazine(TFP,a calmodulin inhibitor).We measured the photosynthetic functions,plant growth and thylakoid membrane integrity at 9 and 10 days after treatment imposition in peanuts.【Results】Compared with CK,P deficiency reduced the dry matter weight,total leaf area,relative chlorophyll concentration and limited the growth and development of peanuts.The P deficiency reduced the net photosynthetic rate,transpiration rate,and stomatal conductance of peanut leaves.It also reduced the efficiency of PSⅠ and PSⅡ of peanuts by 18% and 5.4%,respectively.Compared with –P treatment,exogenous Ca^(2+)enhanced the dry matter weight and total leaf area of peanuts under P deficiency by 26.7% and 31.9%,respectively.Exogenous Ca^(2+) alleviated P deficiency inhibition based on photosynthetic level and enhanced the net photosynthetic rate and the stomatal conductance of peanut leaves under P deficiency.Compared with –P treatment,exogenous Ca^(2+) enhanced the efficiency of PSⅠ and PSⅡ,alleviating the photoinhibition in peanut leaves under P deficiency.Exogenous Ca^(2+) enhanced the size of the PQ pool,the rate of cyclic electron flow,and the activity of ATP synthase.However,it reduced the ?pH of thylakoid in peanut leaves under P deficiency.TFP increased th

关 键 词：外源钙 花生 亚低磷胁迫 光合电子传递 光抑制 

分 类 号：S565.2[农业科学—作物学]