米老排幼苗对不同供氮方式的光合生理响应  

Photosynthetic and Physiological Characteristic of Mytilaria laosensis Seedlings under Different Nitrogen Application

作　　者：于彬[1] 闫彩霞 杨锦昌[1] 尹光天[1] 李荣生[1] 邹文涛[1] YU Bin;YAN Caixia;YANG Jinchang;YIN Guangtian;LI Rongsheng;ZOU Wentao(Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou,Guangdong 510520,China;Gansu Design & Research Institute of Environment Science,Lanzhou,Gansu 730020,China)

机构地区：[1]中国林业科学研究院热带林业研究所,广东广州510520 [2]甘肃省环境科学设计研究院,甘肃兰州730020

出　　处：《热带作物学报》2019年第8期1529-1536,共8页Chinese Journal of Tropical Crops

基　　金：中央级公益性科研院所基本科研业务费专项基金(No.CAFYBB2019SZ002);广东省林业科技创新项目(No.2019KJCX004)

摘　　要：为指导苗期养分科学管理,本研究以温室盆栽的米老排(Mytilaria laosensis)幼苗为材料,采用等量施肥(C)、阶段递增施肥(A)和修正指数施肥(ME)3种方法,每种方法设置50、100、200、400、600mg/株5个氮素水平,并以不施肥为对照,共设置16个处理,分析不同供氮方式对米老排苗木生长的影响。结果表明:米老排叶片净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)均随供氮水平的增加呈现出先增后减的趋势,改善其光合气体交换作用效果最佳的处理是200C>100ME>100A;而胞间CO2浓度(Ci)则随施氮量的增加而总体上表现下降趋势;所有施肥处理中,米老排幼苗叶片叶绿素a含量、叶绿素总量、类胡萝卜素含量和叶绿素a/叶绿素b值均有不同程度的增加;施肥处理显著降低苗期米老排叶片的丙二醛含量和超氧化物歧化酶活性,此外低剂量施肥能够降低叶片中游离脯氨酸含量。等量施肥200 mg/株的供氮方式总体上最有利于改善光合气体交换作用、提高光合作用和降低丙二醛含量。A pot experiment with different nitrogen application, namely conventional, phase additional and modified exponential with five levels (50, 100, 200, 400 and 600 mg/seedling) of fertilization in a greenhouse was carried out to explore the effects of nitrogen fertilization on the growth and to provide references for the management of seedlings nutrition for Mytilaria laosensis. The growth responses were analyzed through the investigation of the photosynthetic and physiological indices of the seedlings selected from each subplot after the experiment. Net photosynthetic rate, stomatal conductance and transpiration rate increased firstly and then decreased with the increasing nitrogen application in all fertilization treatments. The reasonable treatment to improve photosynthetic gas exchange was 200C>100ME>100A. Intercellular CO2 concentration decreased with increasing nitrogen fertilization. Chlorophyll a, total chlorophyll, carotenoid content and Chla/b ratio increased to varied extent, but malonaldehyde content and superoxide dismutase activity decreased significantly for seedlings treated with fertilization. Free proline content reduced when low dose of nitrogen was applied. Nitrogen applicaton of 200 mg/seedling was the best treatment to improve the photosynthetic gas exchange condition, to enhance the photosynthesis and to decrease the malonaldehyde content of M. laosensis seedlings.

关 键 词：米老排 供氮方式 氮素水平 光合生理特性 

分 类 号：S723.133[农业科学—林木遗传育种]