超高产大豆发育期不同节位叶片净光合速率与SPAD值变化分析

Analysis of Net Photosynthetic Rate and SPAD Values of Super-High Yield Soybean Leaves at Different Nodes During Different Developing Stages

为了研究超高产大豆发育期内不同节位叶片的净光合速率(Pn)与相对叶绿素含量(SPAD值)的关系,以超高产大豆品种吉育86为研究对象,以吉育593为对照品种,监测整个生育期不同节位叶片Pn和SPAD值变化,分析超高品种不同节位不同时期Pn与SPAD值变化规律。Pn变化规律为:两个品种下部节位变化规律相似,在R1期达到最大,在R2期下降。高产品种中部节位在R3期达到最大,在R6期下降,对照在R2期达到最大,在R3期下降。两个品种上部节位表现相似,在R5期达到最大,在R6期下降。SPAD值变化规律为:两个品种各节位SPAD值变化规律相似,下部节位在R2期达到最大,在R3期下降。中部节位在R3期达到最大,在R5期下降。上部节位在R5期达到最大,在R6期下降。超高产品种各节位叶片具有更高的SPAD值。Pn与SPAD值相关性表现为,两个品种下部节位两个指标表现为不相关,高产品种中部节位在R3至R7期保持相关,对照在R2至R3期保持相关,超高产品种上部节位在R5至R7期保持相关,对照在R6至R7期保持相关。结果说明超高产品种不同节位叶片整个生育时期具有较高的叶绿素含量,中部节位叶片发育过程中光合功能优势显著,不但维持较高叶绿素含量,而且维持较高的光合速率,中上部节位净Pn与SPAD值保持相关的时期更长。

In order to investigate the relationship between net photosynthetic rate(Pn)and relative chlorophyll content(SPAD value)of leaves at different nodes during the developmental period of super-high-yielding soybean,this study conducted with the super-high-yielding soybean variety Jiyu 86 as the research object and Jiyu 593 as the control variety.We monitored the changes of leaves and Pn and SPAD value at different nodes throughout the reproductive period,and analyzed the changes of Pn and SPAD value at different periods at different nodes of super-high-yielding varieties.The patterns of Pn were as follows,the changes in the lower nodes of the two varieties were similar,reaching the maximum at R1 and decreased at R2 stage.The middle node of the high-yielding variety reached the maximum at R3 and decreased at R6 stage,while the control reached the maximum at R2 and decreased at R3 stage.The upper nodes of both varieties showed similar performance,reaching the maximum at R5 and decreasing at R6 stage.The SPAD value change pattern were as follows,the SPAD value change pattern of each node of both varieties was similar,reached the maximum at R2 and decreasd at R3 in the lower nodes,reached the maximum at R3 and decreased at R5 in the middle node,reached the maximum at R5 and decreased at R6 in the upper node.The leaves at each node of the ultra-high yielding varieties had higher SPAD value.The correlation between Pn and SPAD value were as follows,the two indicators at the lower nodes of the two varieties showed no correlation,the middle nodes of the high-yielding variety remained correlated from R3 to R7,and the control remained correlated from R2 to R3,and the upper nodes of the super-high-yielding variety remained correlated from R5 to R7,and the control remained correlated from R6 to R7.The leaves of the ultra-high yielding varieties had high chlorophyll content at different nodes throughout the reproductive period,and the middle node had a significant photosynthetic functional advantage during leaf development,maintained not only high chlorophyll content but also high photosynthetic rate,and the Pn of the middle and upper nodes remained correlated with SPAD for a longer period.