摘要： 本试验以新梨七号和库尔勒香梨为试材,研究了2个梨品种的光合特性,分析比较了两品种光合作用的共性和特性,结果表明:新梨七号和库尔勒香梨晴天Pn日变化为典型的中午降低型双峰曲线,表现出明显的"午休"现象,阴天条件下新梨七号和库尔勒香梨为单峰曲线。新梨七号"午休"现象较库尔勒香梨明显,且在阴天弱光条件下光合能力强于库尔勒香梨。新梨7号光饱和点和光补偿点分别约为1 392和42μmol/(m².s),表观量子效率为0.048 2mol/mol。新梨七号和库尔勒香梨在可利用光强范围、光合效率、光合能力上存在显著差异。新梨七号叶片在中午高光强下或经强光处理后发生光抑制现象,表观量子效率(AQY)和净光合速率(Pn)显著降低。强光胁迫对新梨七号的影响明显大于库尔勒香梨。

关键词: 库尔勒香梨, 新梨七号, 净光合速率, 日变化, 光抑制

Abstract: Some photosynthetic characteristics of two pear varieties(Pyrus bretschneideri Rehd and Xinli No.7) were studied,Analysis their photosynthesis general character and the characteristic,The results showed: Diurnal change of sunny day in net photosynthetic rate(Pn) in Pyrus bretschneideri Rehd and Xinli No.7 were typical ″none-drop″ bimodal curve,and the phenomenon of″the midday rest″ were obvious.Pn daily variation of cloudless day were the split-blip curve.″The midday rest″ phenomenon in Xinli No.7 was more obvious than Pyrus bretschneideri Rehd,also the photosynthesizes ability under the cloudy day weak light condition was stronger than Pyrus bretschneideri Rehd.The light compensation points and light saturation points approximately was 1 392 and 42 μmol/(m²·s),the apparent quantum yield was 0.048 2 mol/mol.When photoinhibition occurred in Xinli No.7,AQY and Pn decreased obviously.

Key words: Pyrus bretschneideri Rehd, Xinli No. 7, Net photosynthetic rate, Annual changes, Photoinhibition

中图分类号: 

• S661.2