Jonne Rodenburg and Matty Demont
Africa Rice Center (AfricaRice)
Weed-inflicted yield losses in rice equate to half the current rice imports in sub-Saharan Africa (SSA) and African rice farmers have a limited range of effective and affordable weed management technologies. Herbicide-resistance (HR) technologies may have the labor-saving benefits of conventional chemical control without the concomitant phytotoxicity risks. To date, HR rice received only marginal attention in the context of SSA. Here, we review the literature on HR technologies and discuss their potential value for rice ecosystems in Africa. We conclude that HR technologies would provide technically sound solutions for the control of important yield-reducing weeds, such as wild rice in irrigated systems and rainfed lowlands and parasitic weeds in uplands. However, with respect to implementation, these technologies would require effective seed and microcredit systems as much as interested agro-industries. Public-private partnerships and government intervention may provide shortcuts where such conditions are not yet met.
Key words: Weed control, herbicide-tolerant rice, broadspectrum herbicides, glyphosate, glufosinate, imidazolinone, developing countries, poverty.