叶面喷施纳米钼酸钾对油菜幼苗光合特性及氮代谢的影响  

Effects of foliar spraying of nano-potassium molybdate on photosynthetic characteristics and nitrogen metabolism of rapeseed seedlings

作　　者：肖晓璐 段博 蒋展 杨雪 马霓[1] XIAO Xiao-lu;DUAN Bo;JIANG Zhan;YANG Xue;MA Ni(Oil Crops Research Institute,Chinese Academy of Agricultural Sciences,Key Laboratory of Biology and Genetic Improvement of Oil Crops,Ministry of Agriculture and Rural Affairs,Key Laboratory of Crop Cultivation and Physiology of the Ministry of Agriculture and Rural Affairs,Wuhan 430062,China)

机构地区：[1]中国农业科学院油料作物研究所,农业农村部油料作物生物学与遗传育种重点实验室,农业农村部作物生理生态与栽培重点实验室,湖北武汉430062

出　　处：《中国油料作物学报》2023年第5期980-987,共8页Chinese Journal of Oil Crop Sciences

基　　金：国家自然科学基金(31971855);中国农业科学院科技创新工程(CAASASTIP-2021-OCRI)。

摘　　要：为实现作物增产,探明纳米钼酸钾对油菜光合特性和氮代谢的影响机理,以甘蓝型油菜中油杂19为材料,水培条件下对油菜幼苗喷施不同浓度(0~1100 mg·L^(-1))的纳米钼酸钾,测定叶片光合气体交换参数、碳氮同化关键酶活性以及氮含量的变化。结果表明,纳米钼酸钾的喷施增加了油菜叶片光合色素含量,提高净光合速率,降低了蒸腾速率、气孔导度和胞间CO_(2)浓度等气体交换参数。Rubisco和PEPC酶活性随着纳米钼酸钾喷施浓度的增大逐渐增强,喷施浓度为550 mg·L^(-1)和1100 mg·L^(-1)时Rubisco酶活性较对照显著增强,PEPC酶活性在1100 mg·L^(-1)浓度处理下增幅达到显著水平。硝酸还原酶、亚硝酸还原酶和谷氨酸合成酶活性在550 mg·L^(-1)浓度处理下较对照明显增强,浓度过高酶活性则无显著变化。叶片内硝态氮含量在纳米钼酸钾处理后均显著降低,氨态氮含量和氮浓度与对照相比则无显著变化,蛋白质含量在550 mg·L^(-1)浓度处理下较对照明显增加。综上所述,550 mg·L^(-1)纳米钼酸钾在提升油菜碳同化效率的同时,油菜氮同化效率也明显提升。纳米钼酸钾对幼苗光合的促进作用主要与光合色素含量增加、光合作用关键酶活性增强等非气孔因素有关,同时也通过增强氮代谢关键酶活性促进叶片内无机氮向有机氮转化来实现。To improve yield,effects of nano-potassium molybdate was investigated on photosynthetic characteristics and nitrogen metabolism of rapeseed.Different concentrations(0-1100 mg·L^(-1))of nano-potassium molybdate were sprayed on rapeseed seedling under hydroponic conditions.Changes of gas exchange parameters,key enzyme activities of carbon and N assimilation and N contents of leaves were measured.Results showed that spray of nano-potassium molybdate increased photosynthetic pigment and net photosynthetic rate of leaves,while decreased gas exchange parameters(including transpiration rate,stomatal conductance and intercellular CO_(2) concentration).The activities of Rubisco and PEPC enzyme increased gradually with the nano-molybdate concentration,in which Rubisco enzyme activity was significantly enhanced at 550 mg·L^(-1) and 1100 mg·L^(-1) compared to control,and PEPC enzyme activities increased significantly at 1100 mg·L^(-1).The activities of nitrate reductase,nitrite reductase and glutamate synthase were significantly increased at 550 mg·L^(-1) compared with control.No significant change was observed at higher concentrations.Nitrate-N contents were significantly reduced after the spray of nano-potassium molybdate,while ammonia-N contents and N concentrations were not significantly changed compared with control.In addition,protein content increased significantly at 550 mg·L^(-1).In summary,550 mg·L^(-1) nano-potassium molybdate spray enhanced carbon assimilation efficiency of rapeseed,while N assimilation efficiency was also significantly increased.The promotion of photosynthesis in rapeseed by nano-potassium molybdate was mainly related to nonstomatal factors:increased photosynthetic pigment contents and enhanced activities of key enzymes for photosynthesis.It could promote the conversion of inorganic to organic N in rape leaves by enhancing the activities of key enzymes of N metabolism.

关 键 词：油菜 纳米钼酸钾 光合特性 氮代谢 

分 类 号：S565.4[农业科学—作物学]