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.
