In a study on rice and pulse crops, researchers found that a weed called Echinochloa colonum was a major problem, reducing crop yield by 91 percent. They tested different herbicides and found that applying pendimethalin or thiobencarb before planting rice, followed by hand weeding, effectively controlled the weed. These herbicides had some impact on the following pulse crops, especially at higher doses. Another herbicide, fluchloralin, was successful in controlling the weed population in pulses.