【摘要】 氮磷是植物生长的关键养分因子,对植物的生长发育非常重要。通过梯度施肥试验,研究了土壤添加氮磷对考来木Correa carmen光合生理参数和叶绿素荧光参数的影响。结果表明:（1）单施磷肥,考来木叶片叶绿素质量分数、净光合速率（P_n）及荧光最大光化学效率（F_v/F_m）等光合效率指标随着磷肥施用量的增加而下降,初始荧光（F_o）和非光化学猝灭系数(q_NP)等光能耗散指标则随着磷肥施用量的增加而增加。（2）单施氮肥,考来木叶片光合效率指标随着氮肥施用量的增加而增加;当氮肥施用量达247.9 mg·kg^-1后,考来木的光合效率随着氮肥施用量的增加而下降。光能耗散指标则呈相反趋势。（3）磷肥的施用效果随着施氮量的增大而提高,氮肥的施用效果随着施磷量的增大而先升后降,其中低氮高磷和低磷高氮的施肥处理均降低考来木的光合效率。在氮肥施用量为247.9 mg·kg^-1,磷肥施用量为36.3 mg·kg^-1的施肥组合下,考来木的光合效率最高。表明氮磷均具有提高考来木光合效率的作用,但考来木对磷反应敏感、需求量低,在低氮土壤中增施磷肥可降低考来木的光合效率;若氮磷同时增施,可显著提高考来木的光合效率,两者最佳配比为m（氮）∶m（磷）=6.83∶1.00。图2表2参30更多还原

【Abstract】 To ascertain the effects of nitrogen（N）and phosphorus（P）,key nutrients during plant growth,on Correa carmen,twelve gradient fertilization experiments were designed,and the photosynthetic physiological parameters and chlorophyll fluorescence parameters of C.carmen leaves were determined.The seedlings of C carmen were planted in pots with different amount of N fertilizer（NH₄NO₃）and P fertilizer（NaH₂PO₄·2H₂O）P fertilizer doses(calculated by PO₄^3-)were 0,36.3,56.3 mg·kg^-1,respectively.N fertilizer doses（calculated by N）were 0,197.9,247.9 and 297.9 mg·kg^-1,respectively.After 1 month,4 months and 7 months respectively,the photosynthetic physiological parameters of seedling leaves were measured by the CIRAS-3 portable photosynthesis system,such as net photosynthetic rate（P_n）,stomatal conductance（G_s）,transpiration rate（T_r）etc.At the same time,chlorophyll fluorescence parameters were measured by imaging modulation PAM-2500chlorophyll fluorescence spectrometer,too,such as initial fluorescence（F_o）,maximum fluorescence（F_m）,maximum photochemical efficiency（F_v/F_m）,photochemical quenching coefficient（q_P）,non-photochemical quenching coefficient(q_NP),etc.Then N and P contents of leaves were determined by Kjeldahl method and Molybdenum antimony anti-absorption spectrophotometry method,chlorophyll contents were determined by acetone and ethanol mixture extraction method.The variation of experimental data was analyzed by ANOVA and multiple comparison,and the multiple comparison was analyzed by the least significant difference method（LSD）.Results showed that（1）with added P fertilizer alone,the photosynthetic efficiency indexes of C.carmen leaves including chlorophyll content,P_n,and F_v/F_mdecreased（P<0.05）,but light dissipation indexes including F₀and non-photochemical quenching(q_NP)extinction coefficient increased（P<0.05）.（2）With added N fertilizer alone,as dose increased to 247.9 mg·kg^-1,photosynthetic efficiency indexes increased（P<0.05）but decreased（P<0.05）as the dose exceed it.The light dissipation index showed the opposite trend.（3）The application effect of P fertilizer increased with an increase dose of N fertilizer,and the application effect of N fertilizer increased（P<0.05）first and then decreased（P<0.05）with an increased dose of P fertilizer.With less N fertilizer but more P fertilizer or with less P fertilizer but more N fertilizer,the photosynthetic efficiency of C.carmen leaves decreased significantly（P<0.01）.Photosynthetic efficiency indexes were highest when N fertilizer dose was 247.9 mg·kg^-1and P fertilizer dose was 36.3 mg·kg^-1.Thus,C.carmen was sensitive to P with a low demand,and when adding P fertilizer to low-N soils,the photosynthesis efficiency indexes of C.carmen decreased,but when both N fertilizer and P fertilizers were added,they increased greatly.[Ch,2 fig.2 tab.30ref.]更多还原