A new publication, led by experts from the Natural Resources Institute (NRI, University of Greenwich) and the Africa Rice Center (AfricaRice), calls for effective national regulatory capacities to monitor the import, marketing and use of herbicides in sub-Saharan Africa (SSA) and the need for reliable information sources for smallholder farmers concerning proper and safe herbicide use.
The authors also call for increased investments in research and development to innovate and diversify the currently followed weed management strategies, agricultural service provision and communications with farmers in SSA.
The article entitled “Status quo of chemical weed control in rice in sub-Saharan Africa” was published open access on 23 January 2019 in the Springer journal Food Security. [Citation: Rodenburg, J., Johnson, JM., Dieng, I. et al. Food Sec. (2019).
Reporting on results of surveys conducted in 20 countries in SSA, the article reveals that controversial herbicides like glyphosate and 2,4-D are widely used by rice farmers in SSA, as these products dominate the rural agro-chemical supply markets and are sold at competitively low prices.
But what is even more alarming, according to the authors, is that most of these herbicide products, which are generally imported from outside SSA, are not registered and quality-controlled in the country where they are retailed and used.
The surveys also show that SSA rice farmers are often not well informed on the appropriate use of these products and therefore apply them incorrectly, especially with regard to the timing of the sprays, which renders these herbicides ineffective and even detrimental to the rice crop.
The authors caution that overreliance on a small range of herbicide formulations in SSA and the frequent use of these formulations in herbicide brands of unknown quality applied at sub-optimal timings may cause negative impacts on the environment, human health, and the crop, and may accelerate the evolution of herbicide-resistant weed ecotypes.
AfricaRice and its partners have developed several tools to address the knowledge gaps in effective and sustainable weed management practices at the farmer level. Farmer-learning videos have been produced on sustainable weed management and the safe and effective use of herbicides.
In addition, a decision-support mobile app called RiceAdvice WeedManager, launched recently by AfricaRice, aids rice farmers in SSA to diversify their weed management strategies and to use herbicides judiciously.