ABSTRACT
Safe application of prosulfocarb in faba-bean fields in China

Yuan Gao1, Zhaoliang Gao2, Guifang Duan3, Teng Sun3, Guohui Shen1*, and Zhihui Tian1*
 
Although faba-bean (Vicia faba L.) is not a major crop in China, many farmers like to cultivate faba-bean in autumn as a fresh food or animal feed for next spring. However, no herbicides are available to control weeds in the faba-bean fields. Although prosulfocarb is a candidate herbicide, some farmers have reported that prosulfocarb can often cause harm to faba-bean. Our laboratory experiment results revealed that Tongcanxian No. 6, a faba-bean cultivar with large seeds, showed the lowest level of growth inhibition and Qidou No. 2, a faba-bean cultivar with small seeds, showed the highest level of growth inhibition when treated with 3960 and 7920 g ai ha-1 prosulfocarb. The growth inhibition rate of faba-bean was 0% when 3960 and 7920 g ai ha-1 prosulfocarb was sprayed within 6 d after sowing, indicating that prosulfocarb treatment should be applied as soon as possible after sowing. When the temperature exceeded 20 °C and soil moisture content exceeded 20%, it might have aggravated the phytotoxicity of 'Tongcanxian No. 6' and 'Qidou No. 2' caused by prosulfocarb. Two round of field experiments showed visually that the control effect of 3960 g ai ha-1 prosulfocarb on the total weeds exceeded 90% and safe to faba-bean at the same time. This study indicated that prosulfocarb can be safely used in faba-bean fields by improving agronomic methods, which can also provide a reference for weed management in faba-bean fields worldwide.
Keywords: Application time, control effect, faba-bean, prosulfocarb, safety, Vicia faba.
1Eco-Environmental Protection Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.2Forest & Fruit Tree Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.3GreenTec Laboratory, Shanghai Xiaoming Testing Technology Service Co. Ltd., Shanghai 201612, China.*Corresponding author (zb5@saas.sh.cn; tianzhihui@saas.sh.cn).