Comparison of the effect of Roundup Ultra 360 SL pesticide and its active compound glyphosate on human erythrocytes

The effects of exposure of human erythrocytes to different concentrations of Roundup Ultra 360 SL and its active compound glyphosate were studied. We studied hemolysis after 1, 5, and 24 h incubation; lipid peroxidation, hemoglobin oxidation, the level of reduced glutathione, and the activity of catalase after 1 h. Human erythrocytes were incubated with 100-1500 ppm (100 μg/ml erythrocytes at 5% hematocrite) Roundup Ultra 360 SL and glyphosate. We have found that after 1 h of incubation only Roundup Ultra 360 SL increased the level of methemoglobin, products of lipid peroxidation at 500 ppm and hemolysis at 1500 ppm [Curr. Top. Biophys. 26 (2002) 245], while its active compound glyphosate increased the level of methemoglobin and the level of lipid peroxidation at much higher dose—1000 ppm. At the same time hemolysis was observed to only at the highest dose of glyphosate (1500 ppm) and the longest time of incubation (24 h). Both Roundup Ultra 360 SL and glyphosate did not cause statistically significant changes in the level of GSH, but increased the activity of catalase. Roundup Ultra 360 SL provokes more changes in the function of erythrocytes than its active substance glyphosate, which is probably a result of the properties of additives. Taking into account the limited accumulation of Roundup Ultra 360 SL and glyphosate in the organism as well as the fact that the threshold doses which caused changes in erythrocytes for Roundup Ultra 360 SL were only 500 and 1000 ppm for glyphosate, one may conclude that this pesticide is safe towards human erythrocytes.     

蚯蚓粪对柑橘幼苗抗草甘膦胁迫的影响

草甘膦在柑橘园除草中得到大量使用,对农作物生长、果实品质、产量和质量造成影响。如何降低草甘膦对柑橘树的生物可利用性,从而降低其对农作物造成的药害、提高果实品质和食品安全将至关重要。本文在前期研究的基础上通过施用蚯蚓粪,表征蚯蚓粪作用下土壤中残留草甘膦对柑橘幼苗的生物有效性和生物毒性效应。结果显示,蚯蚓粪能够显著增强其生物有效性（BCF值显著增大）;显著降低草甘膦在土壤中的残留量到草甘膦单独处理组的55.15%,从而减少草甘膦在柑橘幼苗植株中的积累。同时,蚯蚓粪的施用能促进植物的茁壮生长,使抗氧化酶活力较对照组显著提高,从而具有更强的抗逆能力。在这两方面的共同作用下,蚯蚓粪显著减轻了土壤中残留草甘膦对柑橘幼苗的胁迫,使其株高、根长和相应的干重较草甘膦单独施用时增长了26.23%-140.11%,甚至成为对照组的1.03倍和1.13倍。此研究对兼顾化肥有机替代的草甘膦污染土壤的修复和高效利用具有重要意义。     

草甘膦、草铵膦喷施对槟榔根系形态及生理的影响

除草剂防除杂草的同时会给非靶标作物带来药害,频繁使用除草剂的海南槟榔园叶片黄化症状更加明显,我们推测除草剂可能导致槟榔根系退化,从而引起叶片黄化。本试验以幼龄期槟榔与成龄期槟榔为研究对象,测定草甘膦和草铵膦使用后槟榔根系生长发育形态与相关生理指标。结果表明：（1）在幼龄期槟榔根系中,主要以直径为0～1.5mm的根为主要根系结构,数量上占到总根的88%以上,表面积占到了总根的68%以上。草甘膦和草铵膦喷施显著降低了槟榔幼苗根系鲜重、干物质积累量,白色吸收根的比例、吸收根活力。（2）在成龄期槟榔气生根中,喷施草甘膦和草铵膦均引起气生根药剂残留,且农残随施用浓度增加而变高;喷施草甘膦和草铵膦,阻碍了槟榔气生根发育。草甘膦处理第14天后气生根死亡数达到最大,而草铵膦处理第28天后达到最大。（3）草铵膦损害了气生根组织结构,使新根内皮层排列稀疏,表皮组织厚度增加,木栓化程度加深,导致根表皮细胞大量死亡,抑制了气生根伸长与增粗。上述研究结果表明草甘膦和草铵膦通过木栓化加速根系死亡调控槟榔根系生长与发育。     

油菜抗除草剂不育系的抗性效应研究

为探明转育获得的抗除草剂不育系的抗性效应,苗期用不同浓度草甘膦处理抗草甘膦油菜不育系TA6,TA7。结果表明:随着喷药浓度增加,对叶片、茎秆和根的生长表现为不同程度的抑制作用,其中对叶片生长的影响较早且最严重,对茎秆生长的影响较迟,程度相对较轻,对根部生长的抑制作用最小,表现为先抑后扬,但随着时间推移,影响程度逐渐减轻,至喷药60 d后,油菜苗生长基本恢复正常。花期育性调查和套袋自交结果表明,抗性不育系喷施草甘膦除草剂后,育性未受任何影响,TA6,TA7的不育率和不育度均表现正常。     

除草剂草甘膦的性质及环境行为综述

草甘膦是一种广谱、非选择性芽后除草剂,它被越来越广泛地应用于农业。本文总结了草甘膦的一些基本性质及其在环境中的行为和降解机理,概述了国内外的研究现状,及影响其在土壤环境去向的一些因素,如土壤性质、磷酸盐、重金属和DOC的存在等,为进一步研究提供一些建设性的参考。     

Diesel and glyphosate price changes benefit the economics of conservation tillage versus traditional tillage

Recent increases in diesel price and decreases in glyphosate [N-(phosphonomethyl) glycine] price should favor the profitability and farmer acceptance of herbicide-intensive conservation tillage systems versus fuel-intensive traditional tillage (TT) systems. Profitability results from a long-term field experiment that compared TT, minimum tillage (MT), and delayed minimum tillage (DMT) systems for winter wheat–(Triticum aestivum L.)summer fallow in eastern Washington, USA were calculated using both 1998 and 2005 input prices. Net returns for the MT and DMT systems increased by US$ 6.37 and 6.30 (rotational ha)⁻¹, respectively, and net returns to the TT system decreased by US$ 2.36 (rotational ha)⁻¹ when 2005 versus 1998 prices were used. Here, rotational ha equals 0.5 ha fallow and 0.5 ha wheat. Focusing on the dominant crop of soft white winter wheat (SWWW), the 2005 price hikes pushed diesel costs up for all systems, from US$ 6.81 (rotational ha)⁻¹ for DMT to US$ 9.00 (rotational ha)⁻¹ for TT. The cost of diesel for the conservation tillage systems, relative to the cost for TT, decreased by US$ 1.50–2.20 (rotational ha)⁻¹. The conservation tillage systems accrue greater savings from the price reduction in glyphosate because they consume more of this herbicide. An unanticipated result was that relative cost savings from price changes in N fertilizer rivaled those from diesel and glyphosate because anhydrous NH₃–N was exclusively used in the experiment for TT and aqueous NH₃–N for MT and DMT. The price of anhydrous NH₃–N increased from US$ 0.55 kg⁻¹ in 1998 to 0.85 kg⁻¹ in 2005, a 56% increase. Aqueous NH₃–N only increased from $0.75 kg⁻¹ in 1998 to 0.85 kg⁻¹ in 2005, a 15% increase. The greater price increase for anhydrous NH₃–N penalized the TT system because of its use of this fertilizer. If the same source of N fertilizer were used on all three tillage systems, this fertilizer cost effect would disappear. Nonetheless, the conservation tillage systems still retained a statistically significant profitability advantage over TT even if the same fertilizer was used throughout. The sharp price increase for diesel and the concurrent price decrease for glyphosate herbicide favored the conservation tillage systems over TT in this study. Results provide strong evidence for the superior profitability of conservation tillage winter wheat–summer fallow under current economic conditions.     

抗草甘膦栽培大豆种质挖掘及抗性生理研究

利用田间试验结合生物化学分析研究了不同的栽培大豆品系对草甘膦的抗性,试验结果显示:在草甘膦有效剂量为0.31~0.92 kg·hm~(-2)时,不同栽培大豆品种对草甘膦抗性存在明显差异,在草甘膦剂量为0.92 kg·hm~(-2)时,石豆1号存活率为100%,表现了较高的抗性,8份材料的存活率为4%~48%,表现出一定的抗性;44份材料表现敏感,存活率为0。试验研究了抗性材料石豆1号、中抗材料Williams和敏感材料中黄35对草甘膦的生理生化反应的差异,结果表明:随着草甘膦处理剂量的增加和处理时间的延长,石豆1号莽草酸含量、叶绿素含量和超氧化物歧化酶(SOD)相对活性没有明显变化。而Williams和中黄35的莽草酸含量和SOD相对活性明显升高,叶绿素含量明显降低。结果表明草甘膦(浓度0.92 kg·hm~(-2))处理下,不同抗性栽培大豆叶片中莽草酸含量有明显差异,处理5~14 d时敏感材料叶片中莽草酸含量保持较高水平,因此栽培大豆叶片莽草酸含量可以作为判断其对草甘膦抗性高低的主要生理指标之一,而SOD的活性和叶绿素含量可以作为判断栽培大豆对草甘膦抗性的辅助生理指标。     

草甘膦对土壤微生物量及呼吸强度的影响

以中国褐土、黄绵土、风沙土和红壤4类土壤共10个土样为材料,较为系统地研究了草甘膦对土壤微生物量、土壤呼吸及代谢墒的影响。结果表明,在碱性土壤中,草甘膦对微生物碳和微生物氮有一定的抑制作用;在酸性土壤中,草甘膦对微生物碳和微生物氮有一定的激活作用。这揭示出土壤性质对草甘膦的毒性有重要影响,特别是pH。草甘膦对土壤呼吸有轻微激活作用,但土壤代谢熵明显增加,不利于土壤微生物的生长,从而影响土壤品质。碱性和酸性土壤受草甘膦轻度和中度污染的临界质量分数分别为43.8和219.2mg/kg及58.2和291.0 mg/kg。     

两株草甘膦降解菌的菌液浓度和草甘膦含量的动态变化

从农药厂污永处理池的活性污泥中分离得到两株降解有机磷农药的菌株BR13和BR57,研究了两株菌的菌液浓度和草甘膦含量的动态变化.结果表明,在整个发酵过程中,草甘膦的含量都随着两株菌的菌液浓度增大而逐渐降低.分别在发酵65和71 h后,两株菌对草甘膦的降解能力均达到最大.     

施用10%草甘膦水剂对土壤盐碱化的影响

通过室内盆栽模拟试验,研究了10%草甘膦水剂在5种浓度下对土壤盐碱化的影响。结果表明,施药后,土壤的盐碱度(用电导率表示),钠碱化度(ESP),钠吸附比(SAR),总碱度及pH值都明显增大,且随施药次数的增加,上述各项盐碱化指标都不断的增大。虽然土壤各项盐碱化指标的变化还在非盐渍土范围内,但有盐碱化的趋势。