不同水肥条件下白羊草光合生理生态特征研究Ⅰ.光合生理日变化  

Study on the Photosynthetic Characteristics of Bothriochloa ischaemum under Different Water and Nutrient Conditions Ⅰ.Diurnal Variation of Photosynthesis

作　　者：徐伟洲[1] 徐炳成[2] 段东平[3] 牛富荣[3] 

机构地区：[1]西北农林科技大学生命科学学院,陕西杨凌712100 [2]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [3]西北农林科技大学林学院,陕西杨凌712100

出　　处：《草地学报》2010年第5期629-635,共7页Acta Agrestia Sinica

基　　金：中国科学院重要方向项目(KZCX2-YW-QN412);西北农林科技大学基本科研业务费专项项目(QN2009079B01);教育部留学回国人员科研启动基金项目资助

摘　　要：为揭示黄土丘陵区乡土种白羊草(Bothriochloa ischaemum L. Keng.)在不同水肥供应条件下的光合生理特征,本研究采用盆栽控制实验,比较研究了白羊草在2个水分水平(HW-80%FC和LW-40FC%)和3个养分(CK、P和NP)处理下的光合生理日变化特征。结果表明:HW下白羊草光合速率日变化均呈"三峰"型曲线。LW下,P和NP处理呈"双峰"型曲线,CK处理呈"三峰"型曲线,均具有明显的光合"午休"现象。不同水肥条件下白羊草叶片水分利用效率日变化均呈"L"型。HW下,白羊草光合速率日均值无肥处理显著高于其他处理(P<0.05),LW下,3养分处理间白羊草光合速率日均值无显著差异,而不同养分处理下,土壤水分胁迫均显著降低了白羊草光合速率日均值,并使光合"午休"程度加剧,水分是限制白羊草光合生理过程的首要因素。In order to study the photo-physiological characteristics of old world bluestem（Bothriochloa ischaemum L.Keng.） from loess hilly-gully region under different water and nutrient supplies,the diurnal dynamics of photosynthetic characteristics were determined under potted condition with two water treatments（HW-80% FC,LW-40% FC） and three nutrient treatments（CK,P and NP）.Results indicted that the diurnal changes of net photosynthetic rate in old world bluestem presented a three-peak pattern cure under adequate water condition.Under water stress condition,both the P and NP treatments presented a double-peak pattern cure,and the CK treatment presented a single peak curve,showing obvious midday depression of photosynthesis.The diurnal change of photosynthetic water use efficiency presented ＂L＂ pattern cure.The daily mean values of net photosynthetic rate in CK treatment was significantly higher than P and NP treatments under adequate water condition,while there no significant differences in the daily mean values of photosynthesis rate among three nutrient treatments under water stress condition.In different nutrient treatments,water stress significantly reduced the daily mean values of photosynthesis rate and intensified the midday depression of photosynthesis,suggesting that water was the primary factor for limiting photosynthesis of old world bluestem.

关 键 词：白羊草 光合速率 水肥供应 日变化 

分 类 号：S543.9[农业科学—作物学] Q945.11[生物学—植物学]