A study was done to find the best way to control weeds in maize fields that were previously used for growing rice. The researchers tested different herbicides and hand weeding methods. They found that using paraquat herbicide right after planting maize seeds, followed by hand weeding, gave the highest maize yield. This method was as effective as using atrazine and glyphosate herbicides together, followed by hand weeding. So, using paraquat herbicide and hand weeding can help farmers grow more maize in fields that used to have rice.