Study on Canopy Structure and Physiological Characteristics of Super-High Yield Spring Maize

【Objective】 Canopy structure and canopy functional characteristics of super-high yield spring maize populations were studied to reveal the physiological mechanism of formation of super-high yield,which provided a theoretical basis for cultivation of super-high yield spring maize.【Method】The Jinshan 27 was grown under super-high-yield cultivation(SHY) and normal high-yield cultivation(CK) condition in 2009 and 2010 to assess the indexes of canopy structure and physiological characteristics of super-high yield maize.【Result】Compared with normal high-yield cultivation,the super-high yield spring maize had higher leaf area index(LAI),and three-ear leaves was more obvious after silking stage.Leaf angle of different leaf locations was lower and the leaf direction value was higher than normal high-yield cultivation,and particularly in the three-ear.With the process of the growing period,the difference of photosynthetic potential between the super-high-yield cultivation and the normal high-yield cultivation increased.In the silking stage and milking stage,the difference of the net photosynthetic rate of two cultivation modes was not significant,but canopy photosynthetic ability of super-high cultivation was significantly higher than normal high-yield cultivation.From the silking stage to 40 days,SOD and POD activities were higher than the normal cultivation and MDA content lower than the normal cultivation.【Conclusion】The super-high yield spring maize has higher LAI and population photosynthetic potential,smaller leaf angle and higher leaf direction value,and canopy structure is reasonable.The super-high yield spring maize has stronger SOD and POD activities,lower the MDA content,higher net photosynthetic rate and stronger photosynthetic potential.So under the reasonable cultivation technique condition,collaborative gain can be obtained from super-high-yield spring maize community structure and individual function.