遮阴和施氮对黄檗幼苗叶片光合特性和碳氮计量特征的影响  

Photosynthetic Characteristics and C and N Stoichiometry of Phellodendron amurense Seedlings under Shading and Nitrogen Application

作　　者：孙悦燕[1,2] 郭跃东 SUN Yueyan;GUO Yuedong(College of Forestry,Shanxi Agricultural University,Taigu,Shanxi 030801,China;Shanxi Key Laboratory of Functional Oil Tree Cultivation and Research,Taigu,Shanxi 030801,China)

机构地区：[1]山西农业大学林学院,山西太谷030801 [2]山西省重点实验室北方功能油料树种培育与研发,山西太谷030801

出　　处：《西北植物学报》2022年第10期1739-1748,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：山西农业大学科技创新基金(2009018,201219)。

摘　　要：选取大田环境下3年生黄檗幼苗,采用人工控制双因素随机区组试验,在不同光照[全光照(S_(0))、轻度遮光21.4%(S_(1))和重度遮光8.7%(S_(2))]和不同氮添加[无添加对照(F_(0))、轻度添加(F_(1))和重度添加(F_(2))]条件下,测定黄檗幼苗叶片的相对叶绿素含量(SPAD值)、气体交换参数及碳氮化学计量特征,探讨黄檗幼苗对遮阴和施氮的响应机制。结果表明:(1)随着遮光程度增强,黄檗幼苗叶片的SPAD值、蒸腾速率(T_(r))、气孔导度(G_(s))、碳氮比(C∶N)和瞬时光合氮利用率(PNUE)均呈现先增后降的趋势,两种遮光条件下SPAD均显著高于全光照环境;黄檗幼苗叶片的净光合速率(P_(n))、水分利用率(WUE)和气孔限制值(L_(s))逐渐降低;而叶片氮(N)和碳(C)含量均呈先降后升的趋势。(2)随氮添加量增加,黄檗幼苗叶片的P_(n)、WUE、L_(s)、N和C含量均呈先增后降趋势,T_(r)、G_(s)和PNUE则逐渐下降,而C∶N逐渐增加。(3)黄檗幼苗叶片的P_(n)在各光氮组合处理间均无显著差异;SPAD含量以S_(1)F_(0)、S_(2)F_(0)和S_(1)F_(2)处理组合显著较高,而以全光照(S_(0))处理组合显著最低;T_(r)和G_(s)以轻度遮光(S_(1))处理组合明显较高,而以S_(2)F_(1)、S_(0)F_(2)、S_(2)F_(2)明显较低;WUE和L_(s)均以S_(0)F_(2)显著最高,S_(2)F_(2)处理组合显著最低。黄檗幼苗叶片N和C含量在重度遮光/轻度氮添加(S_(2)F_(1))时具有较大值,而其C∶N和PNUE在轻度遮光/无氮添加(S_(1)F_(0))时具有较大值。(4)隶属函数综合评价认为,黄檗幼苗对光氮复合作用总体属中等耐受型,轻度遮光时不添加氮肥(S_(1)F_(0))和轻度氮添加(S_(1)F_(1))及全光照时轻度氮添加(S_(0)F_(1))为适于幼苗生长的光氮组合。研究发现,光环境是影响黄檗幼苗光合作用和更新的主导因子,但黄檗苗期能耐受一定的遮阴胁迫;光照不受限制时,适当增加氮肥有利于黄檗幼苗生长;光照受限(重度遮光)时,施氮则抑�Selecting Three-year-old Phellodendron amurense seedlings in field,we conducted the artificially controlled two-factor randomized block experiment.We analyzed the relative chlorophyll content,gas exchange parameters and carbon and nitrogen stoichiometric characteristics under different light[full light(S_(0)),21.4%light shading(S_(1))and 8.7%severe shading(S_(2))]and nitrogen[no addition control(F_(0)),light nitrogen addition(F_(1))and severe nitrogen addition(F_(2))]stresses,to explore the response mechanism of P.amurense seedlings to shading and nitrogen addition.The results showed that:(1)with the increase of shading,the SPAD value,T r,G s,C∶N and PNUE of seedling leaves increased at first and then decreased,and the SPAD value under the two shading conditions were significantly higher than that in full light.P_(n),WUE and L_(s) decreased gradually,while the N and C contents decreased at first and then increased;(2)With the increase of nitrogen addition,P_(n),WUE,L_(s),N and C contents increased at first and then decreased,while T_(r),G_(s) and PNUE decreased and C∶N increased gradually;(3)There was no significant difference in P_(n) among different light and nitrogen treatments;SPAD value in the combination of S_(1)F_(0),S_(2)F_(0)and S_(1)F_(2)was significantly higher,while that of full light(S_(0))was the lowest.T_(r),G_(s)of light shading(S_(1))were significantly higher,while those of S_(2)F_(1),S_(0)F_(2)and S_(2)F_(2)were significantly lower.WUE and L_(s)were significantly the highest in S_(0)F_(2)and the lowest in S_(2)F_(2)treatment.The N and C contents were higher under heavy shading/light nitrogen addition(S_(2)F_(1)),while C∶N and PNUE were higher under light shading/nitrogen zero addition(S_(1)F_(0)).(4)According to the comprehensive evaluation of membership function menthod,P.amurense seedlings belonged to moderately resistant type to the light and nitrogen interaction effect.The combination of light and nitrogen suitable for seedling growth was no nitrogen in light shading(S_(1)F_(0)),light

关 键 词：黄檗 幼苗 遮阴 氮添加 光合特性 化学计量特征 

分 类 号：Q945.79[生物学—植物学] S718.43[农业科学—林学]