不同磷水平对“锦丰”梨光合及叶绿素荧光特性的影响

以"锦丰"梨为试材,采用水培试验方法,研究了不同磷浓度(0、0.5、1.0、1.5、2.0、2.5 mmol·L^-1)对其叶片光合及叶绿素荧光特性的影响,以期为梨树的合理施肥提供参考依据。结果表明:光合速率(Pn)、蒸腾速率(Tr)、水分利用效率(WUE)、初始荧光(Fo)、最大荧光(Fm)、可变荧光(Fv)、叶绿素a(Chl a)、叶绿素b(Chl b)和类胡萝卜素(Car)均随磷浓度的升高呈先增加后降低的趋势,至1.5 mmol·L^-1处达到最大值,比缺磷处理(0 mmol·L^-1)分别提高78.0%、31.3%、37.2%、9.04%、9.49%、9.57%、42.7%、60.9%和37.8%,表明此供磷水平下,"锦丰"梨叶片光合性能最强。由此可见,在该试验条件下,栽培梨树的最佳磷浓度为1.5 mmo·L^-1。

Effects of Different Phosphorus (P) Levels on Photosynthesis and Chlorophyll Fluorescence Characteristics of 'Jinfeng' Pear

‘Jinfeng’ pear was taken as test material,the effects of different phosphorus(P) levels(0,0.5,1.0,1.5,2.0,2.5 mmol·L^-1) on photosynthesis and chlorophyll fluorescence characteristics of pear leaves were studied by using hydroponics experiment in order to provide theoretical basis forrational fertilization of pear trees.The results indicated that the Pn,Tr,WUE,Fo,Fm,Fv,Chl a,Chl b and Car were increased at firstly and then decreased with the increasing of P concentrations,under the treatment of 1.5 mmol·L^-1,those indexes were the highest,which were increased by 78.0%,31.3%,37.2%,9.04%,9.49%,9.57%,42.7%,60.9% and 37.8% respectively compared with the treatment of 0 mmol·L^-1.The results showed that the photosynthetic performance of ‘Jinfeng’ pear was the best under the phosphorus supply.Therefore,the optimum phosphorus concentration of the cultivated pear was 1.5 mmol·L^-1 under the conditions of this test.