DESIGN AND DEVELOPMENT OF ROTO SEEDER CUM HERBICIDE APPLICATOR FOR DRY SEEDING OF RICE

Abstract

Direct dry seeding is the most adopted method for upland rice cultivation in regions where water scarcity is a major issue. Generally, dry seeding includes the operations such as seedbed preparation, broadcasting of seeds followed by thinning in the field. The entire operations are performed independently which in turn increases the availability of time and labour requirements which directly affect the cost of operation. Hence the mechanization in a combined manner to improve the crop yield and reduce the total cost of operation was very essential in the case of DSR. The post planted operations could be mechanized easily only when the planting is uniform and precise which facilitates the reduction in the cost of production. To harvest good yield from dry seeded rice production it was essential to efficiently control the weed growth in lands. The study was hence aimed to design and develop a rotovator attached seed drill with an attachment of a pre- emergent herbicide application unit. Out of the common seed metering mechanisms, certain advanced technologies of seed metering are adopted for the costly hybrid seeds. Among the different seed metering mechanisms, a fluted roller was selected due to its acceptability in a wide range of variations in the physical properties of seeds. Generally, the fluted rollers were designed and fabricated in nylon to reduce the seed damage with a provision for adjusting the exposure length of the flute. Seven semicircular groves were provided on the periphery with designed dimensions. From the results of laboratory and field evaluations, it could conclude that the machine can be efficiently used for the seeding of high yielding rice varieties with the distribution of 3 to 4 seeds per hill as recommended. Also, the system was able to maintain the row to row and plant to plant seed spacing as 200 mm to 150 mm with allowable variations. From the laboratory analysis of the occurrence of seed spacing with an opto-electronic sensor unit, it was clear that the percentage occurrence of clusters of seeds was observed more perfect at lower speeds with spacing 0 – 2 cm and scattering was observed when speed increases. The developed seeder could perform the operations such as seedbed preparation, sowing, and herbicide application in a single pass.