Glyphosate persistence in seawater

Glyphosate is one of the most widely applied herbicides globally but its persistence in seawater has not been reported. Here we quantify the biodegradation of glyphosate using standard “simulation” flask tests with native bacterial populations and coastal seawater from the Great Barrier Reef. The half-life for glyphosate at 25 °C in low-light was 47 days, extending to 267 days in the dark at 25 °C and 315 days in the dark at 31 °C, which is the longest persistence reported for this herbicide. AMPA, the microbial transformation product of glyphosate, was detected under all conditions, confirming that degradation was mediated by the native microbial community. This study demonstrates glyphosate is moderately persistent in the marine water under low light conditions and is highly persistent in the dark. Little degradation would be expected during flood plumes in the tropics, which could potentially deliver dissolved and sediment-bound glyphosate far from shore.     

Explaining Growing Glyphosate Use: The Political Economy of Herbicide-Dependent Agriculture

The growing use of chemical herbicides for weed control has become a dominant feature of modern industrial agriculture and a major environmental and health concern in agricultural systems worldwide. This paper seeks to explain how and why glyphosate-based agricultural herbicides have become so entrenched in modern agriculture. It shows that a complex interplay among technological, market, and regulatory developments have encouraged a lock-in of glyphosate linked technologies in agricultural systems. These are: (1) the repurposing of glyphosate for use with genetically modified crops; (2) the rise of the generic glyphosate market, which globalized the chemical’s use and encouraged new agricultural uses; (3) new technologies such as digital agriculture and genome editing that interface with glyphosate use; and (4) growing corporate market power and declining public investment in agricultural research programs that constrained innovation in non-herbicide weed control technologies.     

Effect of glyphosate-based herbicide on early life stages of Java medaka (Oryzias javanicus): A potential tropical test fish

Glyphosate is globally a widely used herbicide, yet there is little information on their toxicity to marine fishes. Java medaka, a small tropical fish native to coastal areas in several Southeast Asian countries, is viewed as a suitable candidate for toxicity test and thus was used for this study. Java medaka adults were cultured in the laboratory and the fertilized eggs of the F₂ generation were exposed to different concentrations of glyphosate-based herbicide (100, 200, 300, 400 and 500 ppm) until they hatched. The survival and hatching rates of the embryos, changes in the heart rate and morphological impairments were recorded. Generally, survival and hatching percentage decreased as glyphosate concentration increased. Absence of pectoral fin(s) and cornea, permanently bent tail, irregular shaped abdomen, and cell disruption in the fin, head and abdomen are among the common teratogenic effects observed. Furthermore, risk factor also increased with the increased in glyphosate concentrations.     

抗草甘磷转基因大豆多重PCR检测及假阳性问题探讨

以大豆病基因类似物(RGA)基因为对照,用RR大豆中的外源CaMV35S启动子、CP4-EPSPS引物,应用多重PCR方法,从RR大豆中扩增出预期大小的DNA片段。结果表明:将扩增产物回收后测序,经同源性分析扩增产物为CaMV35S启动子和CP4-EPSPS的一部分序列;多重PCR检测的灵敏度为0.08%;PCR检测过程中产生假阳性的原因是污染和非特异性扩增。