The Sunrice (Ethoxysulfuron 15% WDG) is the post-emergent broad-spectrum herbicide used to control sedge and broad-leaf weeds in transplanted rice. The National Plant Protection Centre (NPPC) conducted the efficacy trial on sunrice against broad-leaf weeds particularly on Potamogeton distinctus (Shochum) for more than 3 years in different locations and it gave a positive result in controlling P.distinctus. The result was presented to the technical release committee and in the year 2019 the product was approved by the technology releasing committee for use in the field to control the broad-leaf weeds in transplanted rice. The dzongkhag and gewog agriculture staff of Paro, Thimphu, Punakha and Wangduephodrang were trained on the usage, application methods and safety aspects of sunrice for further dissemination of the information to the farmers.
At present the Ethoxysulfuron is found to be effective in controlling the broad-leaf weeds like Monochoria vaginalis, Blyxa spp. and P.distinctus and the demand for it has kept on increasing. The concern from the NPPC is the paddy weeds building resistance to the Ethoxysulfuron weedicide after its frequent use and also if applied more than the recommendation dosage.
Within just three years after its release in the field, the NPPC received the informal reports about farmers applying Ethoxysulfuron two to three times in a season which is against our recommendation (one time) and its consequence will be weeds building resistance within next three to five years. For that the NPPC would like to notify the farmers to use the weedicide properly as per the recommended dosage and to use Personal Protective Equipment (PPE) while handling it.
Link for sunrice application user manual