摘要： 基于长期养分定位试验平台,研究了长期养分亏缺条件下夏玉米的光合特征,结果表明:缺P和缺K会导致初始荧光Fo的增加,缺P、缺N会导致最大光化学量子效率(Fv/Fm)、实际光化学效率(Φ_PSⅡ)、电子传递效率(ETR)降低,而缺K对其无显著影响。光合速率的大小变化表现出和Φ_PSⅡ、ETR相似的规律,缺K的情况下光合速率与全NPK相比并没有显著降低,而缺N和缺P的处理光合速率明显降低,尤其是缺P处理,下降了32.86%。通过对光合速率和Φ_PSⅡ、ETR分别进行相关性分析和回归分析发现,光合速率和Φ_PSⅡ、ETR有着显著的线性相关,相关系数分别为0.986和0.988。通过对光响应曲线和CO₂响应曲线的分析,缺N对最大光合速率、饱和光强和饱和CO2浓度的影响要大于缺P的影响。

关键词: 夏玉米, 养分亏缺, 叶绿素荧光, 光合速率

Abstract: Based on the long-term nutrient balance experiment conducted in Yucheng Comprehensive Exp. Sta-tion of CAS,the effects of nitrogen,phosphorus and potassium on the photosynthetic characteristics of summer maize were investigated respectively in this study. Four treatments,namely NP,NK,PK and NPK used as comparison,are selected. In order to study the photosynthetic characteristics of summer maize in the long -term nutrient deficiency conditions,the chlorophyll fluorescence parameter,photosynthetic rate,light response curve and CO₂ response curve of summer maize leaves are measured. The results showed that phosphorus deficiency and potassium deficiency would lead to the increase of initial fluorescence ( Fo). Phosphorus deficiency and nitrogen deficiency would lead to the decrease of the maximal photochemical efficiency ( Fv/Fm) and actual photochemical efficiency (Φ_PSⅡ) and elec-trons transfer efficiency ( ETR),while the lack of potassium alone had no significant effect on the above indicators. Compared with the photosynthetic rate under the conditions of an adequate supply of NPK,the deficiency of potassi-um has not reduce the photosynthetic rate significantly,while the deficiency of nitrogen and phosphorus has lead to an significant decrease of the photosynthetic rate,especially phosphorus deficiency conditions the photosynthetic rate has decreased by 32.86%.The variation of photosynthetic rate follows the same trend of Φ_PSⅡ and ETR variation. The results of statistical analysis showed that there is significant linear correlation relationship between photosynthet -ic rate and Φ_PSⅡ and ETR.The correlation coefficients are as high as 0.986 and 0.988,respectively.By analyzing the light response curve and CO₂ response curve,it is concluded that the impact of nitrogen deficiency on the maxi-mal photosynthetic rate,saturation light intensity and saturation CO₂ concentration is more significant than the im-pact of phosphorus deficiency.

Key words: Summer corn, Nutrition deficiency, Chlorophyll fluorescence, Photosynthesis rate

中图分类号: 

• S513