不同氮浓度对广金钱草苗期生理特性的影响

采用田间试验的方式,设0mg/L,150mg/L,300mg/L,450mg/L和600mg/L5个N浓度处理,研究其对广金钱草苗期叶片气体交换、叶绿素(Chl)含量、可溶性蛋白(SP)含量和硝酸还原酶(NR)活性的影响.结果表明,随着N浓度的升高,广金钱草叶片净光合速率(Pn)和蒸腾速率(Tr)升高,而胞间CO2浓度(Ci)下降,Chl a、Chl b、Chl a b、SP含量以及NR活性也表现为升高.线性回归分析结果表明,Pn、Tr与Chl a、Chl b、Chl a b、SP含量、NR活性之间存在显著的正相关关系,而Ci与Chl a、Chl b、Chl a b、SP含量、NR活性之间则存在显著的负相关关系.因此,施N可以加强广金钱草的光合作用和氮代谢,促进其生长发育.

Effects of different nitrogen concentrations on physiological characteristics of Desmodium styracifolium at seedlings stage

Five nitrogen(N) concentrations including 0 mg/L,150 mg/L,300 mg/L,450 mg/L and 600 mg/L were sprayed on the root of D.styracifolium in field to study the effects of different N concentration on gas exchange,chlorophyll(Chl) content,soluble protein(SP) content and nitrate reductase(NR) activity in leaves of seedlings.The results showed that with an increase of N concentration,the net photosynthesis rates(Pn) and transpiration rates(Tr) in leaves were increased significantly,while the intercellular CO2concentrations(Ci) declined.Meanwhile,the contents of Chl a,Chl b,Chl a b and SP,and the NR activity were also increased.The linear regression analysis results showed that,the Pn and Tr were significantly and positively correlated with the contents of Chl a,Chl b,Chl a b,and the SP,and the NR activity,while there were significant and negative correlations between the Ci and the contents of Chl a,Chl b,Chl a b,and SP,and the activities of NR.Therefore,spraying N could enhance the photosynthesis and nitrogen metabolism,improve the growth and development of Desmodium styracifolium.