硅对NO3^-胁迫下辣椒幼苗生长及氮代谢的影响  

Effects of Si on plant growth and nitrogen metabolism of pepper seedlings under NO3^- stress

作　　者：宋云鹏[1] 龚繁荣[1] 张丽丽[1] 刘凯歌[1] SONG Yunpeng;GONG Fanrong;ZHANG Lili;LIU Kaige(Protected Horticultural Research Institute,Shanghai Academy of Agricultural Sciences,Shanghai Key Lab of Protected Horticultural Technology,Shanghai 201403,China)

机构地区：[1]上海市农业科学院设施园艺研究所,上海市设施园艺技术重点实验室,上海201403

出　　处：《上海农业学报》2020年第5期50-55,共6页Acta Agriculturae Shanghai

基　　金：上海市科技兴农重点攻关项目[沪农科攻字(2015)第6-2-3号];上海市农业科学院设施园艺卓越团队项目(ZY1402)。

摘　　要：以辣椒‘苏椒五号’为试材,通过营养液栽培的方式,研究外源加硅对NO3^-胁迫下辣椒幼苗生长及氮代谢酶活性的影响。结果表明:与对照相比,150 mmol∕LNO3^-胁迫下,辣椒幼苗的株高、根长、干鲜重均降低;叶片中叶绿素a、叶绿素b、类胡萝卜素等光合色素及净光合速率、蒸腾速率等光合能力显著下降;硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、谷氨酸合成酶(GOGAT)、谷氨酸脱氢酶(GDH)等氮代谢酶的活性显著降低,且随着处理时间延长,降低幅度增大;辣椒叶片和根系中的硝态氮和氨态氮含量随着处理时间延长逐渐增加。150 mmol∕L NO3^-+1 mmol∕L Si处理下,辣椒生长势较好,干鲜重增加;叶片中光和色素含量和光合能力增加;氮代谢酶活性有所增加,促进了植物对NO3^-的吸收以及NH4^+向氨基酸的转变,降低了硝态氮和氨态氮的含量。综上,外加一定浓度的K2SiO3可缓解NO3^-胁迫对辣椒幼苗的伤害。To investigate the effects of exogenous silicon on the growth and the activities of nitrogen metabolic enzymes of pepper seedlings under NO3-stress,1 mmol/L K2 SiO3 as Si donor was studied with’Sujiaowuhao’ pepper in nutrient solution.The results showed,compared with the control,the plant height,root length,fresh weight and dry weight were all decreased under 150 mmol/L NO3-stress.Photosynthetic pigments such as chlorophyll a,chlorophyll b and carotenoids in leaves were decreased.The net photosynthetic rate and transpiration rate also decreased significantly.The nitrogen metabolic enzymes activities such as NR,GS,GOGAT,GDH were also significantly decreased,while NO3^-and NH4^+ content of pepper seedlings were increased,and the variations were bigger with time prolonged.Adding 1 mmol/L Si to 150 mmol/L NO3^-,the growth potential,photosynthetic pigment contents,photosynthetic capacity,nitrogen metabolism enzymes activities of pepper seedlings were all increasing dramatically than those of excess NO3^-stress.The increasing of nitrogen metabolism enzymes activities could accelerate the absorption of NO3^--N and the changing from NH4+ to amino acid,reduce the content of nitrate and ammonium nitrogen.In conclusion,a certain concentration of K2 SiO3 could alleviate the damage of NO3-stress to pepper seedlings.

关 键 词：硅 NO3^-胁迫 辣椒 氮代谢酶 

分 类 号：S626.9[农业科学—园艺学]