Abstract:

The experiment was carried out in 2007–2008. The five plant distribution patterns under the same plant density were A: 18 cm×18 cm, B: 27 cm×12 cm, C: 36 cm×9 cm, D: 45 cm×7.2 cm, E: 54 cm×6 cm in row spacing (cm) ×plant spacing (cm), respectively. The results showed that the average leaf area index in A and B treatments was 30% and 25% significantly higher than that in E treatment respectively in the whole growing period access two years. Compared with in E treatment the dry matter accumulation in A and B treatments was increased significantly by 30%, 19% at the whole growing stage in two years, respectively, C, D, and E treatments had no significant difference between each other. The number of pods and pods per branch in A, B, and C treatments were significantly higher than these in E treatment at the whole growing stage in two years, respectively, while there was no significant difference between D and E treatments. A and B treatments were 11%, 10% significantly higher than E treatment in average yield in the two years, respectively, while there was no significant difference between C, D, and E treatments. The leaf area index (LAI) decreased with the increase of row spacing that caused fierce competition for resources, and thus the reduction in dry matter accumulation and distribution, and eventually led the yield to decline. These results indicate that summer soybean population with relatively uniform plant distribution leads to rational dry matter distribution, and higher yield. A and B treatments had no significant difference but B treatment was better for cultivation and management in the actual production process, suggesting that B treatment is the best plant distribution for a population.

Key words: Plant distribution, Summer soybean, Dry matter, Yield