肥密互作对大豆光合作用的调控研究

Study on Regulation of Fertilizer and Density Interaction on Soybean Photosynthesis

为研究肥密因素对大豆光合特性的调控作用,本研究以中龙豆1号为研究对象,设置施氮量和密度各4个处理,研究肥密互作条件下大豆光合特性及叶绿素含量的响应。结果表明:R1~R5期,光合特性呈先升高后降低的单峰曲线变化规律,在R4期光合速率最高;叶绿素含量从R1~R5期呈现上升的趋势,R5期最高。各肥料处理间的光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)及叶绿素含量(SPAD值)均表现为F2>F1>F3>F0;胞间CO2浓度(Ci)表现为F0>F4>F2>F3。各密度处理间的光合速率(Pn)、气孔导度(Gs)和蒸腾速率(E)表现为D3>D2>D1>D4;胞间CO2浓度(Ci)表现为D1>D4>D2>D3;叶绿素含量(SPAD值)均表现为D1>D2>D3>D4。肥密因素对光合特性起到了一定的调控作用,本研究中,在F2D3处理(施氮150 kg·hm^-2,密度32万株·hm^-2)下大豆冠层分布最合理,有利于光合作用的提高。

In order to research the regulation of fertilizer density factors on the photosynthetic characteristics of soybean,this study took Zhonglongdou No.1 as the research object,and set up 4 treatments of nitrogen application amount and density,respectively,to study the response mechanism of photosynthetic characteristics and chlorophyll content of soybean under the condition of fertilizer density interaction.The results showed that at R1-R5 stages,the photosynthetic characteristics showed the change rule of unimodal curve which first increased and then decreased,and the photosynthetic rate was the highest at R4 stage.The content of chlorophyll increased from R1-R5,and R5 was the highest.The photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr)and chlorophyll content(SPAD value)of each fertilizer treatment room were F2>F1>F3>F0.The intercellular CO2 concentration(Ci)was F0>F4>F2>F3.Photosynthetic rate(Pn),stomatal conductance(Gs)and transpiration rate(Tr)in each density treatment were expressed as D3>D2>D1>D4,intercellular CO2 concentration(Ci)as D1>D4>D2>D3,and chlorophyll content(SPAD value)as D1>D2>D3>D4.Fertilizer density plays a certain role in the regulation of photosynthetic characteristics.Under the treatment of F2D3(nitrogen fertilizer was 150 kg·hm^-2 and density was 320000 plants·hm^-2),soybean canopy distribution was the most reasonable,which was conducive to the improvement of photosynthesis.