玉米行距变化对间作系统生产力及玉米生长的影响

间作系统中作物种间距离的变化直接影响着系统的生产力，因此，合理的种间配置是间作获得高产的前提。本研究总结归纳了2010年甘肃武威和2014年甘肃张掖的小麦/玉米、蚕豆/玉米间作系统玉米行距试验，旨在探明间作玉米在不同种植行距下对间作体系生产力的影响及玉米生长的差异。试验设置5个间作玉米的种植行距处理（D0：10 cm、D20：20 cm、D40：40 cm、D60：60 cm、D80：80 cm），测定了作物产量、产量构成、生物量累积。结果表明：间作玉米行距变化对间作配对作物产量无显著影响，主要影响间作玉米产量； 2010年，两间作体系间作玉米产量、体系混合产量、系统生产力（system productivity）均以D60最高，2014年均以D40最高；随玉米行距增大，系统生产力先增加后减小，拐点均出现在D60；玉米行距变化显著改变了玉米的穗粒数、百粒重、单株粒重；小麦/玉米体系，两年单株粒重峰值分别出现在D60（132 g·株^-1）和D40（216 g·株^-1）；蚕豆/玉米体系均出现在D40，分别为158 g·株^-1（2010年）和220 g·株^-1（2014年）；不同行距处理下玉米共生期和单独生长期生长速率均存在差异，共生期各处理生长速率显著低于单独生长期，无论哪个时期，D40和D60处理的生长速率均占优。河西灌区小麦/玉米和蚕豆/玉米间作中玉米种植的最佳行距为40 cm和60 cm，此行距下间作系统可得到最大系统生产力。

Effects of Maize Row Spacing on System Productivity and the Growth of Intercropped Maize in Intercropping System

The change for row spacing of intercropped maize directly affects production of intercropping system, therefore, it is necessary for high yield of intercropping system to match reasonable row spacing. Two field experiments (a experiment was conducted at Wuwei in 2010 and another at Zhangye in 2014 in Gansu Province) were carried out to determine the effect of row spacing of intercropped maize on intercropping system production and growth of intercropped maize in two intercropping systems (wheat/maize and faba bean/maize). The experiments included 5 maize row spacing treatments (D0:0 cm, D20:20 cm, D40:40 cm, D60:60 cm, D80:80 cm),the yield, agronomy traits and growth of intercropped maize were investigated. The results showed that there were no significant effects of row spacing of intercropped maize on yield of intercropped companion crops, row spacing change mainly affected the yield of intercropped maize; the yield of intercropped maize, the total yield of intercropping system and SP (system productivity) under D60 in 2010 and D40 in 2014 were the greatest in both intercropping systems. With increasing of row spacing of intercropped maize, SP increased firstly, and then decreased, a inflection appeared at D60. The ear grain number, the 100-grains weight and grain weight per plant were significantly affected by different row spacing treatments, the peak value was 132 g·plant^-1 (D60) in 2010 and 216 g·plant^-1 (D40) in 2014 in wheat/maize intercropping system, and 158 g·plant^-1 (D40) in 2010 and 220 g·plant^-1 (D40) in 2014 in faba bean/maize intercropping system. The growth rate of intercropped maize during co-growth period was significant lower than those during single growth period, the growth rate under D40 and D60 was always greater than other treatments in any sampling period. Therefore, the reasonable row spacing of intercropped maize was 40 cm and 60 cm in wheat/maize and faba bean/maize intercropping in Hexi corridor, the system production was the greatest.