The Effect of Cultivation Method Combining Narrow Rows and Wide Ridges on the Yield of a Wheat Cultivar for Bread ‘Setokirara’

Abstract

In western Japan, wheat is generally sown on 1.5 to 2 m wide ridges with rows 0.3 m apart, but this cultivation method does not fully use the sunlight irradiated on the drainage furrows. In this study, we examined whether a combination of 4.5 m ridge width omitting two drainage furrows and double the number of rows without changing sowing density (WR-NR) could improve light use efficiency, yield and grain quality of wheat cultivar for bread ‘Setokirara’ for four seasons. WR-NR showed a similar or higher yield than the conventional method in all four seasons. The higher yield in WR-NR was due to the higher crop growth rate from heading to maturity. The grain protein content in WR-NR was maintained high due to high aboveground nitrogen accumulation at maturity even when yield increased. We measured the changes in plant height and culm length, internode length and internode dry weight per unit length at two weeks after anthesis in the fourth season. The results showed that plant height in WR-NR remained lower than that in the conventional from the fourth leaf appearance to two weeks after anthesis. Also, WR-NR produced heavier internode dry weight per unit length, both in the main stems and tillers, thus reducing the risk of lodging. WR-NR was an effective cultivation method to increase wheat yield and grain quality in western Japan while reducing the risk of lodging.