氮磷钾肥配施对‘玉露香梨’叶绿素含量及光合特性的影响

‘Yuluxiang'Pear: Nitrogen, Phosphorus and Potassium Fertilizers Affect Chlorophyll Content and Photosynthetic Characteristics

为研究氮磷钾肥配施对‘玉露香梨’光合特性的影响效应,以10年生‘玉露香梨’树为研究对象,使用便携式光合作用测定仪和叶绿素仪测定氮磷钾肥配施后‘玉露香梨’叶片净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Cs)、胞间CO_2(Ci)、水分利用率(WUE)及叶绿素含量(Chl)等光合指标。结果显示,氮、磷肥处理后梨树叶片Pn、WUE和Chl显著升高,氮肥处理组中Tr、Ci和Cs则显著降低;Pearson分析显示,氮磷肥施用量与Pn、WUE和Chl呈正相关性,氮肥与Tr和Cs值呈负相关性显示氮可能通过影响Cs,降低叶片的Tr,减少叶片水分的散失;钾肥处理组中各指标均无显著变化。研究表明,施用氮肥和磷肥可显著提高水分利用率、促进叶绿素合成,并有效提升‘玉露香梨’叶片光合生产效率。

To study the effects of nitrogen, phosphorus and potassium fertilizers on photosyntheticcharacteristics of‘Yuluxiang’pear, taking 10-year-old‘Yuluxiang’pear trees as the study objects, wemeasured the net photosynthetic rate(Pn), transpiration rate(Tr), stomatal conductance(Cs), intercellular CO2 concentration(Ci), water use efficiency(WUE) and chlorophyll content(Chl) after applying nitrogen,phosphorus and potassium fertilizers by using the portable photosynthesis determinator and chlorophyll meter.The results showed that: Pn, WUE and Chl in pear leaves after the nitrogen and phosphorus fertilizer treatmentsignificantly increased, while Tr, Ci and Cs of the nitrogen fertilizer group significantly reduced; Pearsonanalysis showed a positive correlation between the application amount of nitrogen, phosphorus fertilizer and Pn, WUE, Chl, and a negative correlation between nitrogen fertilizer and Cs and Tr suggested that nitrogenmight reduce the loss of leaf moisture by affecting Cs, reducing the Tr of the leaves; no significant differencesbetween the control and the potassium fertilizer group were observed. In conclusion, the nitrogen andphosphate fertilizers could significantly increase the water use efficiency, promote the synthesis of chlorophyll,and improve the photosynthetic production efficiency in leaves of‘Yuluxiang’pear.