乙草胺·莠灭净悬乳剂防除玉米田杂草试验初探

40 %乙草胺·莠灭净悬乳剂是乙草胺与莠灭净的复配剂。为了明确对玉米田杂草的防除效果及对玉米的安全性 ,2 0 0 2年我们进行了玉米田小区药效试验 ,现将试验结果报告如下。1　材料与方法1 1　供试药剂供试药剂为 4 0 %乙草胺·莠灭净悬乳剂。对照药剂为 5 0 %乙草胺乳油和 4 0 %莠灭净可湿性粉剂 ,均为无锡瑞泽农药有限公司提供。1 2　试验设计试验共设 7个处理 :(1) 4 0 %乙草胺·莠灭净悬乳剂 2 0 0ml/6 6 7m2 ;(2 ) 4 0 %乙草胺·莠灭净悬乳剂2 5 0ml/6 6 7m2 ;(3) 4 0 %乙草胺·莠灭净悬乳剂 30 0ml/6 6 7m2 ;(4) 4 0 %乙草胺·莠灭净…     

68％2甲4氯·敌草隆·莠灭净WP等防除甘蔗田杂草的效果

68％2甲4氯·敌草隆·莠灭净WP可防除甘蔗田禾本科杂草和多种阔叶杂草.推荐剂量防除阔叶杂草和禾本科杂草防效与80％敌草隆SC、80％莠灭净WP相当,对阔叶杂草防效较56％2甲4氯SP好.从经济和安全考虑,推荐剂量为1 950～2 850 g/hm2,在甘蔗苗期,杂草2～4叶期茎叶喷雾处理.     

两种除草剂防除蔗田杂草试验

试验结果表明,55%二甲四氯异辛酯.莠灭净乳油在150~200ml/667m2剂量下、80%阿灭净在100~120g/667m2剂量下可有效防除大多数蔗田杂草,且对甘蔗安全,在杂草2~4叶期施药防治效果最佳。     

80％莠灭净可湿性粉剂防除冬种免耕马铃薯田间杂草试验

80％莠灭净、卯400倍液防除马铃薯田间各种杂草总防效达98．0％,与10％草甘膦AS50倍液防效相当,但比使用草甘膦AS安全,可大面积推广应用。     

环磺酮防除甘蔗田杂草的应用效果

为明确环磺酮应用于甘蔗田防除杂草的可行性,本文通过田间药效试验和安全性试验,验证其科学性。结果表明,8%环磺酮OD用量60～120 g a.i/ha,在甘蔗3叶期至封行前,杂草生长茂盛期对甘蔗安全,无明显药害症状,与莠灭净混用后,增效明显;8%环磺酮OD 90～120 g+80%莠灭净WP 1 500 g a.i/ha,在甘蔗3叶期至封行前,杂草生长茂盛期,按照亩用水量60 L兑水稀释后均匀喷施于杂草叶片,药后30 d防效90%以上。     

近期批准登记的农药

登记号登记名称作物(防治对象)企业电话LS2007062748%2甲4氯钠·莠灭净可湿性粉剂甘蔗田(一年生杂草)辽宁省营口三征北农种衣剂有限责任公司0417-3635160LS200706284.5%高效氯氰菊酯乳油十字花科蔬菜(小菜蛾)江西新兴农药有限公司0794-8621067LS2007062925%喹硫磷乳油水稻(二化     

化学农药环境安全评价试验准则(续)

3.1.6 土壤淋溶作用试验在农业上使用的农药,都要提供淋溶特性资料。淋溶作用与吸附作用密切相关,可利用吸附常数估计农药在土壤中的移动性。淋溶试验可用土壤柱淋溶法或土壤薄层层析法测定。用土壤柱淋溶法测定时,对易降解的农药,最好同时测定降解作用。试验时可模拟农药使用地区的气温与降雨条件,并提供土     

冬麦不同施磷水平下土壤磷素淋溶试验

盆栽冬小麦条件下设置常规施磷,2倍施磷,4倍施磷三个施磷水平,观测不同磷肥施用量及施用方式对土壤磷素淋溶的影响,结果表明:①随着磷肥施用量的增加,淋出液中总磷(TP)浓度也随之提高,可溶性无机磷(MRP)占TP的比例也明显增加,而可溶性有机磷(DOP)占TP的比例却明显降低.②施肥方式不同,磷素淋失的特征也不同,集中施肥(磷肥施在表层3 cm内或与一半土壤混合)能明显地减少磷素淋溶出土体,而与土壤混合均匀施用磷肥会增加磷素的淋溶量,且与土壤混合施用磷肥也会增加可溶态磷的淋溶量.③淋溶发生的时间对磷素的淋溶也有影响,最先淋溶出土壤的磷是附着在细小土壤颗粒上的(PP),它们随着土壤中的优先流流出;其次是有机磷(DOP),与土壤的吸附较弱.随着水分的增加以及淋溶的延续,更多的可溶性磷被溶解而随水流出土壤(MRP).④土壤磷素含量较低时,主要是可溶性有机磷(DOP)淋溶出来,当土壤含磷水平高或施磷(无机磷肥)量大时,可溶性无机磷(MRP)就成为淋溶的主要形态.     

多壁碳纳米管固相萃取气相色谱-串联质谱法测定乌龙茶及土壤中10种三嗪类除草剂残留

建立了乌龙茶及土壤中10种三嗪类除草剂(西玛津、莠去津、扑灭津、特丁津、敌草净、环丙津、西草净、莠灭净、扑草净和特丁净)残留的气相色谱-串联质谱(GC-MS/MS)分析方法。样品经乙腈提取后,以多壁碳纳米管(MWCNTs)、N-丙基乙二胺(PSA)、C18、MgSO4为净化剂分散净化后,在GC-MS/MS多反应监测(MRM)模式下进行测定,空白基质匹配标准曲线外标法定量。研究了不同提取溶剂、不同吸附剂种类及用量对提取净化效率的影响。结果表明:在各自质量浓度范围内(西草净和扑草净在10~500 μg/kg,其余8种除草剂在5~500 μg/kg)具有良好线性关系,相关系数(r)均大于0.99,10种三嗪类除草剂的定量限(LOQ)为5.0~10 μg/kg。在5~100 μg/kg添加水平下,10种三嗪类除草剂在乌龙茶和土壤中的平均回收率在75%~111%之间,相对标准偏差(RSD)在3.1%~8.7%(n=6)之间。该方法操作简单、净化效果好、灵敏度高,具有良好的适用性,能够满足乌龙茶及土壤中10种三嗪类除草剂残留分析测定的要求。     

单嘧磺酯在土壤中的淋溶特性研究

建立了单嘧磺酯在土壤中的分析方法,并采用土壤薄层法研究了单嘧磺酯在我国具有代表性的3种土壤中的淋溶特性。结果表明,单嘧磺酯土壤中分析方法的回收率为77.7～105%,相对标准偏差为2.51～9.06%,最低检出浓度为0.218mg/kg。单嘧磺酯的土壤淋溶研究结果表明,单嘧磺酯在河南、内蒙古和云南土壤中的Rf值分别为0.75、0.75和0.59;在采集自河南和内蒙古的土壤中的移动性能为可移动;在采集自云南的土壤中的移动性能为中等移动。单嘧磺酯的土壤淋溶特性与土壤的理化性质密切相关。土壤pH越小、土壤粘粒含量越高,单嘧磺酯的土壤淋溶性越弱。     

盐碱地不同施氮量对土壤微生物区系与食葵产量的影响

在内蒙古河套灌区盐碱食葵田进行大田试验,以不施氮肥为对照(CK),设置了75 kg·hm~(-2)(N1)、150kg·hm~(-2)(N2)、225 kg·hm~(-2)(N3)、300 kg·hm~(-2)(N4)、375 kg·hm~(-2)(N5)五个氮肥施用水平,研究了不同氮肥施用量对土壤微生物区系和食葵产量的影响。结果表明:(1)盐碱地施用氮肥可提高土壤微生物数量和细菌优势菌菌群多样性,各处理0~20 cm土层根区土壤微生物数量大小顺序为N4N3N5N2N1CK,各施肥处理较CK差异极显著(P0.01);(2)盐碱地施用氮肥可促进食葵生长发育,提高产量,随氮肥施用量由低到高,食葵长势和干物质积累呈逐渐增加趋势,产量与施氮量呈抛物线型关系,各处理产量分别较CK提高0.06%、36.27%、61.95%、105.36%和85.03%;(3)适量施氮可抑制土壤积盐,食葵收获后,各处理积盐量大小顺序为N2CKN5N3N1N4;(4)土壤微生物的数量和优势菌菌群数与氮肥施用量、食葵根干重呈正相关关系,与土壤含盐量和积盐量呈负相关关系。综合试验结果,内蒙古河套灌区中度盐碱地食葵生产中氮肥适宜施用量为300 kg·hm~(-2)。     

Quantifying interactions between compound properties and macropore flow effects on pesticide leaching

The objective of this study was to investigate the interactions between compound properties and macropore flow effects on pesticide leaching. To this end, the dual‐porosity MACRO model was used to simulate leaching of 60 hypothetical compounds with widely differing sorption and degradation characteristics using a pre‐calibrated scenario from Lanna, south‐west Sweden, representing a structured clay soil. The model predicts that, in the worst case, macropore flow increases leaching by more than four orders of magnitude for moderately to strongly sorbed compounds with relatively short half‐lives. However, it was also notable that leaching of some very mobile compounds is actually reduced by macropore flow. For pesticides leaching between 0.0001 and 10% of the applied dose (without macropore flow), the impact of pesticide properties on leaching is markedly reduced. This suggests that reductions in applied dose become a relatively more attractive and effective means of decreasing leaching from structured soils. © 2000 Society of Chemical Industry     

Movement and rate of decomposition of ethoprophos in soil columns under field conditions

The rates of degradation and downward movement of ethoprophos (O-ethyl SS-dipropyl phosphorodithioate) were measured under field conditions in four soils in aluminium columns (40 cm long). A 10% granular formulation was incorporated in the top 10 cm at a rate of 10.0–10.5 kg a.i./ha. Under outdoor conditions during spring and summer, loss of ethoprophos approximated to first order kinetics; the half-life was about 87 days in a humic sand and a peaty sand, with pH values of 4.5 and 4.6, respectively. In a sandy loam and a loam soil with pH values of 7.2 and 7.3, respectively, the half-life ranged between 14 and 28 days. Under experimental conditions with fallow soils and 35.3 cm rainfall, the downward movement of substantial concentrations of ethoprophos by leaching and diffusion was restricted to a few centimetres.     

七种农药在3种不同类型土壤中的吸附及淋溶特性

采用振荡平衡法和土柱淋溶法研究了2,4-滴酸、丁噻隆、毒草胺、炔草酸、氟环唑、甲基磺草酮和烯啶虫胺7种农药在江西红壤、太湖水稻土及东北黑土3种不同理化性质土壤中的吸附及淋溶特性,探讨了农药性质及土壤理化性质对供试农药在土壤中吸附、淋溶行为的影响。结果表明:农药的水溶性越大,其在土壤中的吸附性越弱,淋溶性越强;农药在土壤中的吸附性与土壤pH值、有机质含量以及阳离子交换量之间有较好的相关性。土壤pH值、有机质含量以及农药性质是影响农药在土壤中淋溶及迁移的主要因素。     

双氟磺草胺在不同类型土壤中的吸附与淋溶特性研究

农药在土壤中的吸附和淋溶特性是评价其环境行为的重要指标。采用批量平衡法和土柱淋溶法,研究了双氟磺草胺在小麦种植区3种代表性土壤中的吸附和淋溶特性。结果表明:双氟磺草胺在安徽黏土、山东砂质壤土和河南砂质黏壤土中的吸附规律均可以较好地用Freundlich方程描述,其吸附系数(Kf)在0.39~0.62之间;土壤有机碳归一化吸附系数(Koc)在66.91~81.35之间,表明双氟磺草胺在3种土壤中均属于难吸附型;吸附自由能(ΔG)在-10.90~-10.42kJ/mol之间,均属于物理吸附。双氟磺草胺在3种土壤中的淋出率在71.7%~74.1%之间,说明其在3种土壤中的淋溶性均较强。双氟磺草胺初始添加量和腐殖酸对淋出率具有一定影响。综合试验结果,认为双氟磺草胺在3种土壤中的吸附和淋溶可能受土壤有机质含量、黏粒含量、阳离子交换量和土壤pH值等多个因素的综合影响,其对地下水的污染风险较大,因此应引起高度重视。     

Adsorption, transport and degradation of fipronil termiticide in three Hawaii soils

BACKGROUND: The behavior of the termiticide fipronil in soils was studied to assess its potential to contaminate ground and surface water. This study characterizes (1) adsorption of fipronil in three different soils, (2) transport of fipronil through leaching and runoff under simulated rainfall in these soils and (3) degradation of fipronil to fipronil sulfide and fipronil sulfone in these soils. RESULTS: The adsorption experiments showed a Freundlich isotherm for fipronil with K_oc equal to 1184 L kg^?1. In the leaching experiments, the concentration of fipronil and its metabolites in leachate and runoff decreased asymptotically with time. The concentration of fipronil in the leachate from the three soils correlated inversely with soil organic carbon content. The degradation experiment showed that the half‐life of fipronil in the soils ranged from 28 to 34 days when soil moisture content was 75% of field capacities, and that 10.7–23.5% of the degraded fipronil was transformed into the two metabolites (fipronil sulfide and fipronil sulfone). CONCLUSION: Fipronil showed large losses through leaching but small losses via runoff owing to low volumes of runoff water generated and/or negligible particle‐facilitated transport of fipronil. The half‐life values of fipronil in all three soils were similar. Copyright © 2011 Society of Chemical Industry     

环丙酰草胺在土壤中的迁移特性

为研究环丙酰草胺在土壤中的吸附迁移规律，分别采用批平衡法和柱淋溶法测定了环丙酰草胺在江西红壤、太湖水稻土、常熟乌杉土、陕西潮土和东北黑土5种土壤中的吸附和淋溶特性，并运用数学模型对其在土壤中的吸附及迁移特性进行了分析。结果表明:环丙酰草胺在5种土壤中的等温吸附曲线符合线性吸附方程，吸附常数K_d在1.41~7.08之间；环丙酰草胺在5种土壤中的淋溶性大小依次为:东北黑土>陕西潮土>常熟乌杉土>太湖水稻土>江西红壤。通过对吸附常数K_d与土壤有机质含量和pH值的关系进行分析，发现土壤pH值在吸附过程中属主要因素，K_d与土壤pH值呈负相关。上述结果表明，环丙酰草胺在供试的5种土壤中比较容易迁移，影响其迁移的主要因素是土壤pH值。环丙酰草胺在使用过程中应关注其对地表水和地下水造成的风险。     

Fate of glyphosate in soil and the possibility of leaching to ground and surface waters: a review

The very wide use of glyphosate to control weeds in agricultural, silvicultural and urban areas throughout the world requires that special attention be paid to its possible transport from terrestrial to aquatic environments. The aim of this review is to present and discuss the state of knowledge on sorption, degradation and leachability of glyphosate in soils. Difficulties of drawing clear and unambiguous conclusions because of strong soil dependency and limited conclusive investigations are pointed out. Nevertheless, the risk of ground and surface water pollution by glyphosate seems limited because of sorption onto variable-charge soil minerals, e.g. aluminium and iron oxides, and because of microbial degradation. Although sorption and degradation are affected by many factors that might be expected to affect glyphosate mobility in soils, glyphosate leaching seems mainly determined by soil structure and rainfall. Limited leaching has been observed in non-structured sandy soils, while subsurface leaching to drainage systems was observed in a structured soil with preferential flow in macropores, but only when high rainfall followed glyphosate application. Glyphosate in drainage water runs into surface waters but not necessarily to groundwater because it may be sorbed and degraded in deeper soil layers before reaching the groundwater. Although the transport of glyphosate from land to water environments seems very limited, knowledge about subsurface leaching and surface runoff of glyphosate as well as the importance of this transport as related to ground and surface water quality is scarce.     

三种拟除虫菊酯类农药在砂土和壤土中的淋溶行为

采用土柱淋溶法和气相色谱法研究了3种拟除虫菊酯类农药三氟氯氰菊酯、联苯菊酯和高效氯氰菊酯在热带地区主要土壤类型砂土和壤土中的淋溶特性。结果表明:3种拟除虫菊酯类农药在砂土和壤土中主要残留于第1段土壤 (0～5 cm) 中,且驻留量随土壤深度增大而减少。三氟氯氰菊酯、高效氯氰菊酯和联苯菊酯在砂土中的R_i值分别为52.86%、94.73%和83.19%,在壤土中的R_i值分别为54.70%、77.28%和55.33%,均大于50%。根据农药在土壤中的淋溶性等级划分标准,3种药剂均属于难淋溶农药,不易对地下水造成污染。本研究结果可为热带地区土壤和地下水中农药污染修复提供参考。     

阿拉善荒漠区5种植物叶片性状的季节动态

植物叶片性状研究是植物生态学的热点研究领域之一。以阿拉善地区荒漠植物霸王(Zygophyllum xanthoxylum)、沙冬青(Ammopiptanthus mongolicus)、驼绒藜(Ceratoides latens)、白刺(Nitraria tangutorum)和无芒隐子草(Cleistogenes songorica)为研究对象,采集不同物候期的叶片,分析叶片性状的季节变化特征。结果表明:(1)5种荒漠植物叶片性状在生长季内变化规律不同,即使同种生活型灌木叶片性状也有很大差别。(2)叶片单叶面积和单叶重量在单个植物物种以及整体水平上均表现出显著的幂函数方程曲线。(3)植物叶片元素(C、N、P、K、Ca、Na、Mg)含量在生长季内波动较大,而4种微量元素(Fe、Mn、Zn、Cu)含量在生长季内随月份变化不大,其中,5种植物叶片Zn和Cu含量均维持在"低"水平,对整体植物叶片元素含量变异系数的排序为:NaKPMgZnCaFeCuNMnC。(4)对植物叶片性状之间的相互关系分析显示,在单个物种水平上,5种植物叶片性状之间的相关性差别较大;在整体水平上,植物叶片单叶重量、单叶面积和比叶重与元素C和Cu表现出协同关系,与其余元素均表现出相反的关系。