What herbicide is used to control rice barnyardgrass? Rongjie is a highly effective herbicide.

Rongjie is a rice field herbicide newly developed by Dow AgroSciences of the United States, with penoxsulam (25 g/L oil suspension concentrate) as its main ingredient. Years of trials and demonstrations have proven that Rongjie is particularly outstanding in controlling rice barnyardgrass, a vicious weed in paddy fields in Northeast China.

In the rice fields of the Fushun area, there are two types of barnyardgrass: water barnyardgrass and rice barnyardgrass. Water barnyardgrass has no auricle or ligule, while rice barnyardgrass, though also lacking an auricle and ligule, has fine hairs on the internodes between the leaf and leaf sheath. In recent years, after conventional barnyardgrass-killing herbicides were applied in rice fields, water barnyardgrass has been effectively controlled, but rice barnyardgrass, which has developed resistance to barnyardgrass-killing herbicides, has increased markedly and grown luxuriantly, becoming a major dominant weed in rice and a serious headache for rice farmers. With no solution at hand, in 2007 the Agricultural Science Station of Pingdingshan Town introduced and tested Rongjie for controlling rice barnyardgrass and achieved marked results.

Application method: Carry out foliar treatment at the 2-3 leaf stage of barnyardgrass, using 40-80 mL of 25 g/L Rongjie oil suspension concentrate per mu, mixed with 20 kg of water for spraying. Before application, drain the water from the field or ensure that more than 2/3 of the weed stems and leaves are exposed above the water surface. Irrigate within 24-72 hours after application.

Main herbicidal characteristics: (1) Outstanding control effect on rice barnyardgrass. (2) Effective against most weeds in rice fields, including barnyardgrass, annual sedges (Cyperus difformis, Eleocharis acicularis, etc.) and most broadleaf weeds, including Monochoria vaginalis, Monochoria korsakowii, etc. (3) Also excellent control effect on older barnyardgrass.

Mechanism of action: According to relevant literature, Rongjie is absorbed through weed leaves, stems and roots, and is translocated via the xylem and phloem to the meristematic tissue to take effect. Symptoms of weeds treated with Rongjie: (1) Growth stops quickly. (2) 2-4 days after application, the weed growing points fade, and some leaf veins turn red. (3) 7-14 days after application, stem tips and leaf buds begin to wither and necrose, and the stem base of barnyardgrass turns black. (4) 2-4 weeks after application, the weeds die. (5) Ungerminated weeds generally die before emergence or grow slowly after emergence until they die at the 1-2 leaf stage.

Safety to rice: Rongjie is very safe for japonica rice. Years of field trials and demonstrations in various regions have proven that Rongjie, at the normal recommended dose, is safe for rice (except in seedling fields). Under uneven spraying or low-temperature conditions, rice may sometimes turn yellow for a short time, generally recovering within 5-7 days.

In 2007, Xinbin County promoted and applied Rongjie over more than 10,000 mu to control rice barnyardgrass in paddy fields, achieving marked results and solving a major weed-control problem for the vast number of rice farmers.