种植行距对春玉米干物质积累动态及分配规律的影响

在东北黑土区,以先玉335和军单8两个玉米品种为试验材料,在70、65、60、50 cm 4种种植行距下,研究不同春玉米品种干物质积累、转移、分配规律及子粒产量的差异。结果表明,生育后期50 cm和70 cm行距下的干物质积累量显著高于60 cm和65 cm行距处理;干物质在子粒中的分配比例,70 cm和50 cm行距处理显著高于65 cm和60 cm行距处理;70 cm和50 cm行距处理下玉米干物质积累总量高,能够保持较高的子粒积累量。70 cm和50 cm行距处理到生育末期保持了较高的营养器官分配比例,延缓了叶、茎、鞘等光合器官衰老,延长了功能期。其他器官向子粒的干物质转移主要来自茎和叶,但是转移量都不超过子粒总量的6%,子粒产量的主要来源是光合产物的积累和直接分配。

Effect of Different Row Spacing on Dynamic of Dry Matter Accumulation and Distribution

Xianyu335 and Jundan 8 were used as the materials, and there were four row spacing treatments, 70 cm, 65 cm, 60 cm and 50 cm, respectively. A field experiment was conducted to investigate the dynamic and rules of dry matter accumulation, distribution, transportation and grain yield in the black soil region of Northeast China. The results showed that, dry matter accumulation in 50 cm and 70 cm row spacing was more than the others in the late growth stage, dry matter distribution in the proportion of grain among the treatments showed 70 cm < 50 cm < 65 cm and 60 cm. The distribution of dry matter ratio of grain between the treatments showed the rules of 70 cm < 50 cm < 65 cm and 60 cm. Higher accumulation of grain was in 50 cm and 70 cm row spacing due to the highest dry matter accumulation. Compared with other treatments, the 70 cm and 50 cm treatments had a higher distribution to vegetative organs in late growth stage, indicating that leaves, stems, sheaths and other photosynthetic organs senescence and functional period was delayed and extended respectively. Dry matter of grain transferred from other organs was mainly from stems and leaves, but the amount was not large, no more than 6% of the total grain, indicating that the main source of grain yield was still photosynthetic products and direct distribution.