玉米-大豆带状套作高产玉米品种的形态特征

通过两年大田试验,在玉米-大豆带状复合种植模式下,研究21个玉米品种在净作和套作模式下的产量水平,以产量为7 500 kg/hm~2为界限,将供试玉米品种划分为3个产量类别,通过比较净作高产套作高产与净作高产套作低产两个类别下玉米的形态特征,从品种间形态的变异系数和形态指标与产量相关性,筛选出叶面积、株高、穗上位二叶夹角和穗位高可作为选择套作高产玉米品种的主要形态指标。套作玉米品种叶面积吐丝期为6 415～7 158 cm~2/株,穗上位二叶夹角分别为20°～31°和22°～28°,株高为259～280 cm,穗位高为94.5～113.0 cm时,可获得较高的套作玉米产量。

Morphological Characteristics of High-yield Maize Varieties in Maize-Soybean Relay Strip Intercropping System

Two field experiments were conducted to investigate the yield potential in sole and intercropping systems using various maize varieties(n=21) in maize-soybean relay strip intercropping system. Based on yield levels, the maize varieties were categorized into three groups, i.e., maize yield in sole and intercropping system higher than 7 500 kg/ha(S^HI^H), yield higher than 7 500 kg/ha in sole but lower than 7 500 kg/ha in intercropping system(S^HI^L), and yield lower than 7 500 kg/ha in both sole and intercropping system(S^LI^L). We further investigated the plant morphological characteristics under different yield levels. Based on variation coefficient of morphological characteristics and correlation between morphological characteristics and yield, we observed that morphological characteristics such as leaf area, leaf angle above ear-position, height and ear height as were main indicants of high maize yield in intercropping system. However, we speculate that the leaf area per plant was the main parameter that was significantly affected the yield in S^HI^L. It is enticing to report that maize in SHIH group had high leaf area(6 415-7 158 cm²/plant). Two leaf angles above ear-position of plants in S^HI^H group were 20°-31° and 22°-28°. To sum-up, high yield of maize was correlated with the height and ear position. The yield was higher when the height of maize was around 259-280 cm and ear position around 94.5-113.0 cm.