A Weed Wiper developed by scientists at the Kerala Agricultural University has been awarded a patent. The invention of KAU Weed Wiper has given new direction to the efforts for countering the growth of weedy rice (Vari in local parlance) in paddy fields of the State.
Weedy rice is a product of natural hybridisation between cultivated rice and wild rice. Morphological and biochemical similarity of weedy rice to cultivated rice makes hand weeding and herbicidal control ineffective. As a result, weedy rice infestation has become a serious threat in the rice tracts of Kerala. Severe infestation and subsequent reduction in yield by 50-70 per cent has forced many farmers to abandon rice cultivation.
The technology was transferred to Raidco Kerala , a State-owned enterprise and the product is available in the market. The novel wiper device was designed as part of the doctoral programme of Nimmy Jose, scientist at Rice Research Station, Moncompu of KAU. The research conducted by her under the guidance of CT Abraham, former Professor and Head, All India Coordinated Research Project on Weed Control, KAU, could also standardise an integrated strategy for the management of the highly persistent weedy rice in paddy fields. The research programme was granted the best PhD thesis award in 2015 by the Indian Society of Weed Science.
Weedy rice is generally taller by 15-30 cm than cultivated rice at about 55-60 days after sowing. The weed wiper makes use of this height difference to ensure selective application of herbicides on weedy rice plants and thus destroy them. Since the technology makes restricted application possible without contaminating soil or crops, the device is fast gaining popularity among farmers.