2022 Volume 21 Issue 2 Pages 229-235
We would like to introduce and promote open field cultivation of vegetables, such as directly sown onions, in regions devastated by the Great East Japan Earthquake in Fukushima Prefecture. In particular, directly sown onions, in contrast to transplanted onions, do not require a greenhouse to grow seedlings. This can significantly reduce the time spent on raising seedlings and settled planting. In the field, the growth period of directly sown onions is longer than that of transplanted onions. It is important to reduce damage caused by weeds after sowing, since growth immediately after sowing is slow, which makes it easy for weeds to compete with the crop. Therefore, this study examined the influence of both the single and combination of multiple herbicides on growth and yield of direct-sown onions in autumn in Fukushima Prefecture. The herbicidal effect of a single treatment of dazomet or prosulfocarb was insufficient for some weed species. We demonstrated that weed control can be achieved by spraying prosulfocarb in combination with either dazomet (which can be used up to 14 days before sowing) or cyanazine (which can be used after sowing and before emergence). The results of this study show that weeds can be controlled by combining multiple herbicides without having any effect on growing onion crops or the final yield, by sowing the onion crop directly in the fall.
