Slow-Release Formulations of Sulfometuron Incorporated in Micelles Adsorbed on Montmorillonite

详细信息    查看全文

• 作者：Yael Golda Mishael ; Tomas Undabeytia ; Onn Rabinovitz ; Baruch Rubin ; and Shlomo Nir
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2002
• 出版时间：May 8, 2002
• 年：2002
• 卷：50
• 期：10
• 页码：2864 - 2869
• 全文大小：99K
• 年卷期：v.50,no.10(May 8, 2002)
• ISSN：1520-5118

文摘

The design and tests of slow-release formulations of sulfometuron (SFM), an anionic sulfonylureaherbicide, are described. The formulations are based on incorporation of the herbicide in octadecyltrimethylammonium (ODTMA) micelles, which adsorb on a clay mineral, montmorillonite. Anoptimization of herbicide/micelle clay ratios yielded high adsorption of SFM (95%), and at a 1% (w/w) water suspension only 0.5% of the adsorbed SFM was released at times varying from hours to 9days. An analytical test in Seville soil showed that under excessive irrigation (400 mm) 100% of thecommercial formulation leached, whereas the micelle-clay formulations showed only 50-65% elution.A plant bioassay in Rehovot soil showed that the commercial dispersible granule formulation (Oust,75% ai sulfometuron methyl) yielded only 23% root elongation inhibition at the top 5 cm of the soil,whereas complete inhibition was achieved with the micelle-clay formulation. The detected concentration of SFM for the micelle-clay formulation at a depth of 15-20 cm was half of that detected for thecommercial one, indicating a reduction in leaching when applying the micelle-clay formulation. A10-fold reduction in the applied dose of SFM in the micelle-clay formulations resulted in goodherbicidal activity of 60-87% inhibition. These characteristics make the new formulation promisingfrom the environmental and economic points of view.Keywords: Octadecyltrimethylammonium; micelles; montmorillonite; sulfometuron; slow release; soilcolumn; bioassay