DEVELOPMENT OF A GRANULAR HERBICIDE APPLICATOR ATTACHED TO RICE TRANSPLANTER

A granular herbicide applicator attached to conventional ride-on rice transplanter with 6 rows was developed in order to carry out both transplanting and herbicide application at once. It resulted in labor saving by 98%. The prototype is composed of a metering device and a spinning disc spreader. The application rate per 10a can be varied from 1 to 3 kg and the application swath is 1.8 m, which is the planting width of the ride-on rice transplanter with 6 rows. The angular speed of spinning disc and the application height were used as design factors to obtain the uniform distribution of herbicide granules. As the result of experiment, the distribution uniformity showed a tendency to be proportional to the increases of both spinner angular speed and application height. The prototype with angular speed of spinning disc of 7359 rpm and the application height of 20 cm was made and its distribution uniformity was relatively uniform with the CV(coefficient of variation) of 21.7%. In field test, when the tested herbicides such as ACl40+Stomp and Londax+YRC were applied, the weed control has continued for 65 days since transplanting was done.