Demand for Novel Herbicides Grows in China
Demand for Novel Herbicides Grows in China
By Zhang Weinong
In China, the crop acreage using chemical herbicides has now reached 53 million hectares, over 10 times that of 1980. The land needing herbicides increases by 2 million hectares every year. Over 80 000 tons of herbicide active ingredients are used in China every year. By now, more than 100 types of herbicides have been used in China. Among them, the top 20 accounted for about 75% of the market share in 2006, calculated by area of application. Bensulfuron-methyl, metsulfuron-methyl, 2, 4-D (2, 4-dichlorophenoxyacetic acid), MCPA, atrazine, prometryn, simetryne, acetochlor and butachlor are the mainstream varieties of herbicides in the Chinese market. In recent years, with changes in farming systems and the weeds' increasing resistance to old herbicides in farmland, novel herbicides' share of the chemical herbicide market is growing. They now account for about 30% - 40% of the total consumption of herbicides in China.
China has used herbicides in rice fields for over 20 years. Barnyard grass has developed resistance to quinclorac, while sedges and broadleaf weeds have become resistant to bensulfuron-methyl. In addition, China has been promoting a new way for cultivating rice in recent years. This has put forward higher requirements on the control of weeds in paddy fields. The 10% flucetosulfuron WP is welcome in the market because it can control barnyard grass and broadleaf weeds in rice fields. Flucetosulfuron is a new type of sulfonylurea herbicide jointly developed by Korea's LG Life Sciences Ltd and Korea Research Institute of Chemical Technology. Flucetosulfuron active ingredient and 10% flucetosulfuron WP were registered in China in 2007. Novel herbicides developed by Chinese companies for the control of barnyard grass in paddy fields, such as molinate, thiobencarb, pyrazosulfuron and bispyribac-sodium, also occupy a certain market share in China. Because of the long-term use of glyphosate and paraquat in direct-sown rice fields in China, the population of herbicide-resistant weeds has increased. In recent years, in Shanghai municipality, Jiangsu, Zhejiang, Guangdong and Guangxi provinces, the use of diquat, which is a novel contact herbicide, has increased. Because diquat has a fast and broad-spectrum weed-control efficacy and especially it can effectively control weeds that have resistance to glyphosate and paraquat, it is very welcome by farmers.
With the rise of wheat prices, the wheat acreage in the valleys of the Yellow River, Huaihe River, Haihe River and Yangtze River has been increasing sharply. In the early 1980s, the major wheat herbicides were butachlor, MCPA and 2, 4-D butyl. In recent years, new and effective wheat herbicides have been introduced into the market. Due to their high performance vs. cost ratio, chlortoluron and chlorsulfuron are widely used. As an efficient, low-toxicity and safe new-type wheat herbicide, the market demand for triasulfuron is also increasing sharply. In addition, the demand for super-efficient imported wheat herbicides like tribenuron-methyl, sigma and Derby-c is also rising rapidly. According to statistics, these novel wheat herbicides account for about 30% of the market in China.
In recent years, China's corn acreage has been stable at 25.5 - 26.5 million hectares and accounts for 1/5 of the global corn acreage. Nicosulfuron is a major corn herbicide, and its patent has been expired. As of May 31st, 2009, there were a total of 24 Chinese enterprises and one foreign company registered in China to produce nicosulfuron active ingredient. These companies include Hefei Xingyu Chemical Co Ltd, Jiangsu Fengshan Group, Xinyi Zhongkai Agrochemical Co Ltd, Sinochem Ningbo (Group) Co Ltd and Anhui Huaxing Chemical Industry Co Ltd. In China, the total capacity, consumption and export volume of nicosulfuron active ingredient were 2 000 tons, 500 tons and 1 500 tons per year respectively. Because nicosulfuron is cheaper than imported corn herbicides, it is always in short supply in boom seasons in recent years.
Among soybean seedling herbicides, the sales and usage of metolachlor are better than propisochlor and alachlor. At present, there are 14 Chinese enterprises and 1 foreign company that have registered in China to produce soybean seedling herbicide active ingredients. In addition for domestic use, about 60% of these products are exported. In face of competition from other herbicides, the market share and price of acetochlor has constantly dropped. Due to its broad-spectrum and high efficacy, metolachlor is welcome in the market.
Over 400 varieties of herbicides have been registered in China, of which nearly 90 varieties were registered by foreign companies. IP rights to most super efficient, low-toxicity and low-persistence herbicides are possessed by foreign companies. In recent years, Chinese research institutions and enterprises have strengthened their development of new and innovative products. They have developed a number of high-efficiency, low-toxicity and low-persistence herbicides, such as haloxyfop-etotyl, quizalofop-p-ethyl, fenoxaprop-p-ethyl and fluazifop-P-butyl. Among these innovative herbicides, monosulfuron and monosulfuron-ester developed by Nankai University School of Chemistry have filled China's long-term millet herbicide market vacancy. Since monosulfuron and monosulfuron-ester were industrially produced, demand for them in China has been stable.