草业学报2013，Vol.22Issue(4)：319-326,8.DOI:10.11686/cyxb20130437
氮肥、刈割强度对桂牧1号杂交象草光合特性的影响
Effect of nitrogen fertilization and cutting intensity on the photosynthetic characteristics of Pennisetum purpureum cv.Guimu No.1
摘要
Abstract
The effects of nitrogen fertilization (250 kg/ha and unfertilized) and cutting intensities (5 cm,20 cm,or 50 cm above ground level) on the photosynthetic characteristics of Guimu No.1 (Pennisetum purpureum cv.Guimu No.1) were studied in a two factor randomized experiment.All the diurnal variations of net photosynthetic rate (Pn) in the six treatments followed a bimodal curve distribution.However,with an increase of cutting intensities,the Pn initially rose but then declined and with nitrogen fertilization,the noon break phenomenon of photosynthesis was reduced.Nitrogen fertilization increased chlorophyll content and the maximum net photosynthetic rate (Amax).With an increase of cutting intensities in the N-fertilization treatments,apparent quantum efficiency (AQE) increased,while carboxylation efficiency (CE) initially increased but finally declined; the reverse was true for the light compensation point (LCP),photorespiratory rate (Rp) and dark respiration rate (Rd).With an increase of cutting intensities in treatments with no N-fertilization,AQE,LCP,CE,Rp and Rd all declined initially but then increased.This indicated that both nitrogen fertilization and cutting intensity have some influence on the photosynthetic characteristics of Guimu No.1 with the best effect from a combination of medium-intensity cutting and 250 kg/ha nitrogen.关键词
桂牧1号杂交象草/氮肥/刈割强度/净光合速率/光响应/CO2响应Key words
Pennisetum purpureum cv.Guimu No.1/ nitrogen fertilization/ cutting intensity/ net photosynthetic rate/ light response/ CO2 response分类
农业科技引用本文复制引用
梁志霞,杜虎,彭晚霞,曾馥平,杨钙仁,谭秋锦,宋同清..氮肥、刈割强度对桂牧1号杂交象草光合特性的影响[J].草业学报,2013,22(4):319-326,8.基金项目
中国科学院西部行动计划项目(KZCX2-XB3-10),国家科技支撑计划(2011BAC09B02),中国科学院战略性先导科技专项(XDA05050205,XDA05070404),国家自然科学基金项目(No.31000224,31070425,U1033004)和中国科学院"西部之光"人才培养计划资助. （KZCX2-XB3-10）
