Abstract:
Rice is the staple food of Kerala and is the most important food crop
grown. However, the area under paddy cultivation has come down from 8.82 lakh
ha in 1974-75 to 1.96 lakh ha in 2015-16. Adoption of mechanized farming is a
widely accepted solution for the reversal of this trend. In view of the present
scenario, machinery use in the intercultural operations in paddy cultivation,
mainly weeding, is of much importance. Traditionally, the most common method
of weed control is manual hand weeding by labourers. Recently, mechanical and
chemical weed control methods are becoming popular. But the environmental
problems associated with chemical weeding and the high initial cost and
maintenance cost of power weeders limits their use, especially among marginal
farmers. To overcome this, brush cutters were tested and assessed to know its
suitability for paddy weeding. But due to the vibration hazards and discomfort to
the operator, prolonged use was not possible. Even if a suitable configuration of
the rotor is done, man power was needed for weeding. Thus, brush cutters were
not suitable for paddy weeding. Another approach to wetland paddy weeding
introduced was the refinement and development of a weeding attachment to mini
tiller. Hence, a study was undertaken with the following objectives:
• Assessment of powered weeders for paddy weeding.
• Development of a wetland paddy weeding attachment to mini tiller.
• Evaluation of the developed paddy weeding attachment to mini tiller.
The methodology used for the study of three row paddy weeder, brush cutters
and its attachments and the study and development of weeding attachment to mini
tiller for paddy weeding included:
• Agronomic characteristics of machine transplanted rice
• Assessment of powered three row weeder for paddy weeding
o Laboratory tests
o Field evaluation
• Study of brush cutters and their attachments
• Study of existing soil working attachment to kombi type brush cutter
• Study of powered mini tiller
• Suitability of existing powered mini tiller for paddy weeding
• Development of paddy weeding attachment to mini tiller
• Fabrication of rotary weeding attachment
• Fabrication of guards
• Attachment of the rotary weeding unit and guards to mini tiller
• Evaluation of the developed weeding attachment
• Economics of weeder
The salient results
A paddy weeder attachment to mini tiller was designed and fabricated. The
developed weeder was found to be superior to the existing paddy power weeders
viz. TNAU two row weeder and three row power paddy weeder. Cost of operation
per hectare of mini tiller weeder was lowest compared to three-row power weeder
and TNAU two row power weeder. With limited constructional modifications, the
mini tiller can be used as a multi-purpose implement for different operations such
as minor tillage, weeding of vegetable crop as well as paddy weeding which can
improve the annual working hours of the machine.