PURPOSE: To prevent break out of a non-fertilized place by providing a part where a planting clutch is engaged exchangingly instead of a fertilizing clutch at a prescribed time delayed after engagement of the fertilizing clutch at an operational position of a common controller for the planting clutch and the fertilizing clutch.

CONSTITUTION: Operations for engagement-disengagement of a planting clutch and a fertilizing clutch are carried out by a common control lever 70. When the control lever is turned to the position for engagement of both the planting clutch and the fertilizing clutch, the planting clutch is changed to the engagement state at a prescrived time delayed after engagement of the fertilizing clutch by the function of a delay mechanism actuating in the case a working pin 77a for disengagement of the planting clutch and a working pin 77b for engagement of the planting clutch are actuated.