Moghu Research Center Ltd., BVC 311, KRIBB, Yuseong, Daejeon 305-333, Korea.
J Agric Food Chem. 2013 Jul 17;61(28):6799-805. doi: 10.1021/jf400199u. Epub 2013 Jul 3.
Methiozolin is a new turf herbicide controlling annual bluegrass in various cool- and warm-season turfgrasses. This study was conducted to investigate the fate of methiozolin in soil under aerobic and anaerobic flooded conditions using two radiolabeled tracers, [benzyl-(14)C]- and [isoxazole-(14)C]methiozolin. The mass balance of applied radioactivity ranged from 91.7 to 104.5% in both soil conditions. In the soil under the aerobic condition, [(14)C]methiozolin degraded with time to remain by 17.9 and 15.9% of the applied in soil at 120 days after treatment (DAT). [(14)C]Carbon dioxide and the nonextractable radioactivity increased as the soil aged to reach up to 41.5 and 35.7% for [benzyl-(14)C]methiozolin at 120 DAT, respectively, but 36.1 and 39.8% for [isoxazole-(14)C]methiozolin, respectively, during the same period. The nonextractable residue was associated more with humin and fulvic acid fractions under the aerobic condition. No significant volatile products or metabolites were detected during this study. The half-life of [(14)C]methiozolin was approximately 49 days in the soil under the aerobic condition; however, it could not be estimated in the soil under the anaerobic flooded condition because [(14)C]methiozolin degradation was limited. On the basis of these results, methiozolin is considered to undergo fast degradation by aerobic microbes, but not by anaerobic microbes in soil.
灭草松是一种新型草坪除草剂，可防治多种冷季型和暖季型草坪中的一年生早熟禾。本研究采用两种放射性示踪剂[苄基-(14)C]-和[异噁唑-(14)C]灭草松，研究了有氧和厌氧水淹条件下灭草松在土壤中的归趋。在两种土壤条件下，施入放射性的质量平衡均在 91.7%至 104.5%之间。在有氧条件下的土壤中，灭草松随时间降解，在施药 120 天后土壤中仍残留 17.9%和 15.9%的原药。[(14)C]二氧化碳和不可提取放射性物质随土壤老化而增加，在 120 天时，[苄基-(14)C]灭草松分别达到 41.5%和 35.7%，而[异噁唑-(14)C]灭草松分别达到 36.1%和 39.8%。不可提取残留物与有氧条件下的腐殖质和富里酸分数关系更为密切。在本研究期间，未检测到显著的挥发性产物或代谢物。[(14)C]灭草松在有氧条件下的土壤中的半衰期约为 49 天；然而，在厌氧水淹条件下的土壤中，由于灭草松降解受到限制，无法对其进行估计。基于这些结果，灭草松被认为在有氧微生物的作用下迅速降解，但在土壤中的厌氧微生物作用下不降解。
