超高产春玉米冠层结构及其生理特性

 【目的】研究超高产春玉米群体冠层结构和功能特性，揭示超高产形成的生理机制，为春玉米超高产栽培提供理论依据。【方法】以金山27为供试品种，设超高产栽培（SHY）和普通高产栽培（CK）2个处理，于2009年和2010年连续2年的田间试验，测定超高产春玉米冠层结构及生理指标的变化规律。【结果】与普通高产栽培相比，超高产栽培春玉米叶面积指数大，在生育期上表现为吐丝之后更为明显，在叶位上表现为棒三叶最为突出；不同叶位的叶倾角超高产栽培均小于普通高产栽培，而叶向值均大于普通高产栽培，在棒三叶表现最为明显；随着生育时期的推移，超高产栽培与普通高产栽培光合势的差幅增大；吐丝期和乳熟期，两种栽培模式间净光合速率的差异不显著，但冠层光合能力的差异均达到极显著水平；吐丝后40 d内，超高产春玉米叶片SOD和POD酶活性总体上高于普通高产栽培，而MDA含量低于普通高产栽培。【结论】超高产栽培春玉米叶面积指数高，群体光合势大；叶倾角小、叶向值大，冠层结构合理；叶片SOD 和POD活性强，MDA含量低，衰老缓慢，净光合速率相对较高，冠层光合能力强。在合理的栽培技术调控下，超高产春玉米群体结构与个体功能实现了协同增益。

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.