子叶丢失强度和时间对栓皮栎幼苗生长状况和营养物质转移的影响  

Effects of Cotyledon Loss Intensity and Time on Seedling Growth Status and Reserves Translocation in Quercus variabilis

作　　者：姜晓旭 李国雷[1,2] 史文辉 赵凯芬[1,2] 李成 Jiang Xiaoxu;Li Guolei;Shi Wenhui;Zhao Kaifen;Li Cheng(Key Laboratory for Silviculture and Conservation of Ministry of Education,Beijing Forestry University Beijing 100083;Laboratory of Urban and Rural Ecological Environment Beijing 100083;Beijing Dadongliu Nursery Beijing 102211)

机构地区：[1]北京林业大学省部共建森林培育学科与保护重点试验室,北京100083 [2]城乡生态环境北京实验室,北京100083 [3]北京市大东流苗圃,北京102211

出　　处：《林业科学》2018年第8期56-64,共9页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目"叶片性状和根系特性对氮贮存与内转移的作用机制研究"(31670638);北京市共建项目专项"北京乔木类乡土植物筛选及高效繁育技术"(2016GJ-03-06)

摘　　要：【目的】栓皮栎秋季子叶丢失与翌年春季出苗后子叶丢失是自然界的普遍现象,本试验旨在模拟2种丢失现象的交互发生,探究其叠加效应对种子营养物质转移及苗木生长状况的影响,揭示动物取食对栓皮栎幼苗更新的作用机制。【方法】以栓皮栎种子为试验材料,采用双因素裂区试验设计。播种前切除子叶远端,模拟秋季未取食(完整种子)、1/3(轻度)、2/3(重度)3个子叶丢失强度(主因素);出苗后,动态移除子叶,模拟翌年春季出苗后子叶丢失时间(副因素)(出苗后4、8、12、16、20、25、30天移除子叶),同时设置不移除对照组,模拟春季子叶未被取食。测定种子氮和碳水化合物动态含量变化,分析出苗过程中种子向苗木的物质转移规律;生长季末测定苗木成活率、生长、养分积累、非结构性碳水化合物等,分析子叶丢失强度与丢失时间对苗木生长状况的影响。【结果】1)春季出苗30天时,种子中淀粉向苗木的转移率最大(72.4%~89.36%),可溶性糖次之(66.61%~72.72%),氮最小(30.64%~59.45%)。2)秋季未丢失子叶的完整种子翌年春季种子向苗木的氮转移在出苗25天后完成,而秋季丢失子叶的种子春季向苗木转移氮的时间大幅缩短(8天)。3)主效应表明,秋季丢失2/3子叶导致苗高、地径分别降低30%、18%;副效应表明,翌年春季出苗20天前丢失子叶抑制苗木生长。4)交互效应表明,秋季未丢失子叶的完整种子,翌年春季出苗4天丢失子叶成活率仅为36.3%,生物量降低78.2%,25天前丢失子叶抑制养分和碳水化合物积累。秋季丢失1/3子叶的种子,翌年春季出苗4天后丢失子叶成活率降低65.2%,萌发25天后丢失子叶对苗木生长和营养物质积累几乎无影响。秋季丢失2/3子叶的种子,翌年春季无论子叶是否丢失,都会显著抑制苗木生长。【结论】翌年春季出苗后子叶丢失对苗木生长状况的作用不仅取决于丢失时间的早�【Objective】Cotyledon loss of Quercus variabilis in autumn and the following spring after emergence is a common phenomenon in the nature. This study was designed to simulate the interaction of two loss phenomena,and investigate the additive effects on seed reserves translocation and seedling growth,and reveal the mechanism of animal predation on the regeneration of Q. variabilis seedlings. 【Method】In this experiment,the Quercus variabilis seeds were used as experimental material,and two factor split plot design was employed. The cotyledon distal was excised before sowing,to simulate cotyledon loss in three intensities（ main factor） in the autumn,without feeding（ intact seeds）,1/3 feeding（ mild） and 2/3 feeding（ severe）. After seeds emergence,the cotyledon were removed dynamically,to simulatecotyledon loss time（ side factor） in the following spring（ acorns removal on 4,8,12,16,20,25,30 days after emergence）. At the same time,no acorn was removed served as the control to simulate cotyledon no-feeded by animals in spring. Seed nitrogen and carbohydrate content were measured dynamically to analyze the pattern of seed transfer to seedling. Seedlings survival rate,growth,nutrient accumulation and non-structural carbohydrate of Q. variabilis were measured at the end of growing season. 【Results】1） In 30 days after seedling emergence in speing,the translocation rate of starch was（ 72. 4%-89. 36%）,soluble sugar（ 66. 61%-72. 72%）,and nitrogen（ 30. 64%-59. 45%）. 2） The translocation of nitrogen from intact seeds to seedlings was completed in 25 days after seed emergence,and the time for the nitrogen transfer from cotyledon lost seeds in autumn to seedlings was significantly shortened（ 8 d）. 3） The main effects indicated that the loss of 2/3 cotyledon in autumn caused the height and diameter of the seedlings to decrease by 30% and18%,respectively. The side effects indicated that cotyledon loss before emergence 20 days could depress seedling growth at the following sprin

关 键 词：子叶丢失强度 子叶丢失时间 养分供应 碳水化合物 苗木生长状况 

分 类 号：S723.9[农业科学—林木遗传育种] S718.43[农业科学—林学]