目的研究不同杀菌剂组合对人参叶片光合特性的影响。方法应用CI-340型光合作用测定系统,对施用新型药剂组合的人参上举斜立叶片、施用常规药剂组合的人参平展有药斑叶片和清洗后平展无药斑叶片进行光合速率日变化、光响应曲线和CO₂响应曲线测定。结果五年生人参叶片的净光合速率日变化呈双峰曲线,10:00出现第一个峰值。15:00出现第二个峰值。上举斜立叶片、平展无药斑叶片和平展有药斑叶片的光补偿点（LCP）分别为11.5、21.7、41.7 mol/（m²·s）,光饱和点（LSP）分别为1 008、961、954μmol/（m²·s）,CO₂补偿点（CCP）分别为239、240、300μmol/mol,CO₂饱和点（CSP）分别为1 260、1 289、1 300μmol/mol。结论上举斜立叶片的日光合产物高,对光和CO₂环境的适应性强,叶面上的药斑对人参光合作用有负作用。

Objective The effects of various fungicides combination on photosynthetic characteristics of Panax ginseng were studied.Methods The diurnal variation of photosynthetic rate,the light response curve,and the CO₂ response curve of the ascending and oblique ginseng leaf blades with new fungicides combination application,spotted flat ginseng leaf blades with routine fungicides combination application, and flat leaf blades without drug spot after cleaning were measured by using the CI-340 photosynthetic de- termination system.Results The results showed that the diurnal variation of the net photosynthetic rate was two-peak curve on five-year-old P.ginseng leaf blades.The first peak occurred at 10:00 a.m.,the second at 15:00 p.m.The light compensation points(LCP)of ascending and oblique leaf blades,flat leaf blades without drug spot,and the spotted flat leaf blades were 11.5,21.7,and 41.7μmol/(m²·s),re- spectively.The light saturation points(LSP)were 1 008,961,and 954 mol/(m₂·s),respectively.The CO₂ compensation points(CCP)were 239,240,and 300μmol/mol,respectively.The CO₂ saturation points(CSP)were 1 260,1 289,and 1 300μmol/mol,respectively.Conclusion The ascending and oblique leaf blades are higher than the others in the daily outcome of photosynthesis and more adaptable to light and CO₂ environment,the drug spot on leaf blades of P.ginseng has the negative effects on photo- synthesis.

吉林省科技厅资助重大项目(20010202-10)