不同供氮水平对饲料桑树幼苗生长以及光合特性的影响  

Growth and photosynthetic characteristics of forage mulberry in response to different nitrogen application levels

作　　者：许楠[1] 倪红伟[1] 钟海秀[1] 沙威[1] 伍一宁[1] 刑军会 孙广玉[2] 

机构地区：[1]黑龙江省科学院自然与生态研究所/湿地与生态保育国家地方联合工程实验室/黑龙江省湿地与恢复生态学重点实验室,黑龙江哈尔滨150040 [2]东北林业大学生命科学学院,黑龙江哈尔滨150040

出　　处：《江苏农业学报》2015年第4期865-870,共6页Jiangsu Journal of Agricultural Sciences

基　　金：国家林业局林业科学技术成果推广项目[2010-029;(2011)32];东北林业大学学术名师支持计划

摘　　要：为科学制定饲料桑树幼苗氮肥管理措施,在水培条件下以青龙桑为试验材料,设置4个供氮水平(每株0 mg、7.5 mg、15.0 mg和22.5 mg),探求不同供氮水平对桑树幼苗生长及生理特性的影响。结果表明,桑树幼苗株高、地径、叶片数量、叶面积、根长、生物量、叶片净光合速率(Pn)、气孔导度(Gs)、水分利用率(WUE)、蒸腾速率(Tr)均随施氮量的增加而呈现先升高后降低的趋势,根冠比随着施氮量的增加逐渐降低,其中每株施15 mg氮处理的桑树幼苗长势最好;此外,桑树幼苗的叶绿素含量、PSII最大光化学量子产量(Fv/Fm)、光化学猝灭系数(qp)、PSII实际光化学效率(ΦPSⅡ)、电子传递速率(ETR)均随施氮量的增加而升高,非光化学猝灭系数(NPQ)随着施氮量的增加而降低。适宜的供氮量可以增强桑树叶绿体光化学活性和光合能力,并且促进桑树的生长,而过高的供氮水平对其促进效应降低。The characteristics of growth and leaf photosynthesis of mulberry seedlings were investigated under four nitrogen application rates, 0 mg(CK), 7. 5 mg, 15. 0 mg and 22. 5 mg, respectively. Grow parameters such as plant height, ground diameter, leaf number, leaf area, and root length, biomass, and leaf photosynthetic parameters such as leaf net photosynthetic rate, leaf conductance, water use efficiency, and transpiration rate increased first and decreased after-wards as the nitrogen application levels rose. The leaf chlorophyll content, maximum quantum yield of PSⅡphotochemistry ( Fv/Fm ) , photochemical quenching val-ues ( qp ) , actual photochemistry efficiency of PS Ⅱ(ΦPSⅡ), electron transport rate(ETR) increased as the nitrogen application levels went up while the root shoot ra-tio and non photochemical quenching value ( NPQ ) <br> dropped. The nitrogen level at 15. 0 mg per plant exhibited the best grow-promotive effects on forage mulberry.

关 键 词：桑树 施氮量 叶片产量 光合特性 

分 类 号：S945.1[农业科学—水产养殖]