Design, development and evaluation of a manual weeder for Cyperus iria L. in rice fields.

Abstract

Weeding is a crucial task in agriculture that ensures optimal crop growth by eliminating unwanted plants (weeds), which compete for resources and reduce crop yields. Cyperus iria L. (Thunessa) is a serious weed for rice cultivation and it has emerged as an aggressive weed of rice with the ability to multiply rapidly with abundant seed production capacity. Cyperus iria L., commonly known as rice flat sedge, is a persistent and invasive weed that poses a significant threat to rice cultivation. As rice-growing regions have developed weed control options without considering agroecosystem health, weed control has become increasingly important. This study presents the design and development of an innovative new weeder specifically tailored for the effective removal of Cyperus iria L. from rice fields. It features a robust frame equipped with specialized cutting mechanisms designed to sever the weed at its base of inflorescence while minimizing damage to the rice crop. It comprises of V-shaped’ iron spikes mounted on cutting bar that was attached to a power transmission unit. Two ground wheels were used to drive this weeder to forward direction and for the supply power to rotate cutting bar through bevel gears. Rotation of the ground wheels helps for forward driven movement of the machine and changes the direction of cutting bar rotation at the same time. The gear ratio between ground wheels and cutting bar was 1.0: 7.5. Weeding trials were conducted in three experimental plots, each sized 25 m2 and three times per plot. Speed of the machine was measured using 5 m distance and test was replicated 5 times. Results indicated that theoretical field capacity, effective field capacity, field efficiency, average travel speed and weeding efficiency of the weeder were: -0.087 ha/h, 0.0463 ha/h, 53.26 %, 0.456 m/s and 69.93 %, respectively. This newly designed weeder is robust to control Thunessa in paddy cultivation.