PROBLEM TO BE SOLVED: To provide a sowing bed capable of stabilizing budding and initial growth after budding in direct seeding cultivation on an open farm field.SOLUTION: A sowing bed forming device 1 arranged on the rear of a tillage implement, for forming a sowing bed by ridging and forming tillage soil on the front in the traveling direction, includes a ridge formation part 10 including a pair of right-and-left side plates 11, 12 and a top plate 13 provided between the side plates, and a groove formation part 20 extended so that the front part is fixed on the undersurface of the top plate 13, and that the rear part is projected from the top plate. The groove formation part 20 includes a pair of groove wall formation pieces 21, 22 provided on the right and left sides.【課題】露地圃場における直播栽培において、発芽と発芽後の初期育成を安定化させる播種床を形成する。【解決手段】耕耘作業機の後方に配備され、進行方向前方の耕耘土を畝立て成形して播種床を形成する播種床形成器１であって、左右一対の側板１１，１２と側板間に設けられる天板１３を備えた畝成形部１０と、天板１３の下面に前部が固定され後部を天板から突出するように延設させた溝形成部２０とを備え、溝形成部２０は、左右に一対設けた溝壁形成片２１，２２を備える。【選択図】図１
