摘要
为探明毛竹及青冈对铵态氮和硝态氮的偏好吸收特征,通过对毛竹及青冈实生苗的水培试验,设置5种铵硝比(100∶0、75∶25、50∶50、25∶75、0∶100)的营养液处理,测定上述两种植物的叶片SPAD值、根系发育参数、根系中硝酸还原酶活性(NRA)。毛竹实生苗在铵硝比75∶25处理下,其SPAD值、根长、根表面积、NRA显著高于其他处理(P<0.05)。青冈实生苗在铵硝比25∶75处理下,其根长、根表面积显著高于其他处理(P <0.05);SPAD值在铵硝比0∶100处理下显著高于其他处理(P<0.01)。青冈根系中NRA随营养液中硝态氮浓度增加呈线型上升趋势,但毛竹苗培养过程中则无此相关关系。综上,不同氮素形态及配比处理下,毛竹苗在铵态氮为主要氮源时生长优势更明显,青冈苗则对硝态氮同化利用能力更强。
To test the preference of Phyllostachys edulis and Quercus glauca seedlings for nitrateN(NO3--N)and ammonium-N(NH4+-N),we grew their seedlings in hydroponic culture with five different NH4+-N∶NO3--N ratios(100∶0,75∶25,50∶50,25∶75,0∶100),and measured SPAD values of the leave,root morphology,and root nitrate reductase activity(NRA).The results showed that both nitrogen forms and ratios significantly affected growth characteristics of P.edulis and Q.glauca seedlings.SPAD values,root length,root surface area and NRA of P.edulis seedlings were higher in the 75∶25 treatment than in the other treatments(P<0.05).Root length and root surface area of Q.glauca seedlings were higher in the 25∶75 treatment than in the other treatments(P<0.05).The SPAD values of Q.glauca leaves were higher in the 0∶100 treatment with nitrate as the sole nitrogen source than in the other treatments(P<0.01).The NRA in roots of Q.glauca correlated positively with nitrate concentration in nutrient solution,but not for P.edulis seedlings.Our findings indicate that P.edulis prefers ammonium at seedling stage,while Q.glauca prefers nitrate.
作者
王兴萌
陈志豪
李永春
吴家森
李永夫
钟斌
梁辰飞
徐秋芳
WANG Xing-meng;CHEN Zhi-hao;LI Yong-chun;WU Jia-sen;LI Yong-fu;ZHONG Bin;LIANG Chen-fei;XU Qiu-fang(Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration,State Key Laboratory of Subtropical Silviculture,School of Environmental and Resource Sciences,Zhejiang Agriculture and Forestry University,Hangzhou 311300,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2019年第9期2655-2661,共7页
Chinese Journal of Ecology
基金
国家自然科学基金项目(31670618)资助
关键词
硝态氮
铵态氮
根系形态
硝酸还原酶
毛竹
青冈
ammonium
nitrate
root morphology
nitrate reductase activity
Phyllostachys edulis
Quercus glauca
