油酸甲酯助剂对除草剂增效作用及其对玉米苗期安全性测定

采用温室盆栽法测定了自制油酸甲酯助剂对3种玉米田常用除草剂磺草酮、莠去津和烟嘧磺隆药效的增强作用,并测定了该助剂分别与3种除草剂混用后对玉米苗期生长的影响。结果表明:油酸甲酯助剂对供试3种除草剂的药效均有显著增强作用,其中对磺草酮和莠去津药效的增强作用大于对烟嘧磺隆药效的增强作用,且除草剂低剂量使用时油酸甲酯助剂对其药效的增强作用比高剂量使用时更明显;油酸甲酯助剂分别与供试3种除草剂混用对玉米苗期生长有一定影响,以烟嘧磺隆抑制作用较强,莠去津次之。     

5种除草剂对玉米田杂草的防除效果及安全性评价

为明确5种除草剂对玉米田杂草的防除效果及其对玉米的安全性,采用茎叶喷雾施药,通过田间药效试验研究30％苯唑草酮悬浮剂+50％莠去津悬浮剂、35％硝磺草酮·烟嘧磺隆·莠去津可分散油悬浮剂、550 g/L硝磺草酮·莠去津悬浮剂、27％烟嘧磺隆·莠去津可分散油悬浮剂、25％苯唑氟草酮·莠去津可分散油悬浮剂在推荐剂量下对玉米田...     

甲酯化植物油助剂对除草剂的药效增强作用

为明确不同甲酯化植物油助剂对除草剂活性的影响,采用温室盆栽法测定了甲酯化油菜籽油、棉籽油、花生油、玉米油、大豆油、葵花籽油、亚麻籽油和蓖麻油8种甲酯化植物油助剂对磺草酮、莠去津、烟嘧磺隆和精喹禾灵4种常用茎叶处理除草剂防除稗草、反枝苋的影响.结果表明,8种助剂对供试4种除草剂均有不同程度的药效增强作用,其中对磺草酮和莠去津的药效增强幅度大于对烟嘧磺隆和精喹禾灵的药效增强作用,前者为30%～70%,后者则小于20%.相对而言,在供试8种助剂中,以甲酯化油菜籽油、棉籽油和花生油助剂对除草剂的药效增强效果较好,甲酯化玉米油、大豆油和葵花籽油助剂次之,而甲酯化亚麻籽油和蓖麻油助剂对除草剂的药效增强效果较差.     

磺草酮·烟嘧磺隆·莠去津24％悬浮剂防治玉米田杂草田间药效试验

磺草酮·烟嘧磺隆·莠去津24％悬浮剂是玉米田除草剂,主要用于玉米苗后处理,防治一年生杂草。为明确磺草酮·烟嘧磺隆·莠去津24％悬浮剂对玉米田杂草的防除效果及对玉米的安全性,经济有效的用量,2007年进行了田间药效试验,取得了良好的效果。     

7种助剂对7种稻田除草剂的减量增效作用

为明确矿物油、激健、GY-T1602、GY-WS10、GY-W07、GY-S903和NF-100等7种助剂对双草醚、噁唑酰草胺、氰氟草酯、五氟磺草胺、二氯喹啉酸、双唑草腈、嘧啶肟草醚等7种水稻田常用除草剂的减量增效作用,采用整株生物测定法测定除草剂桶混不同助剂对稗草的防效及其对水稻的安全性。结果表明,矿物油、激健、GY-T1602、GY-S903、GY-WS10和NF-100等6种助剂对嘧啶肟草醚、双草醚和氰氟草酯等3种水稻除草剂具有减量增效作用,可减量25～50%;供试7种助剂对五氟磺草胺、噁唑酰草胺、二氯喹啉酸和双唑草腈等4种除草剂均无显著增效作用。根据生物测定结果筛选了11种具有良好减量增效作用的除草剂+助剂组合,分别为双草醚+GY-W07/GY-WS10/GY-S903/矿物油/激健;嘧啶肟草醚+GY-T1602/GY-WS10/NF-100;氰氟草酯+GY-T1602/GY-S903/激健。     

药剂混配防除玉米田杂草试验初报

药剂防除玉米田杂草试验表明,硝磺草酮与烟嘧磺隆、莠去津配伍使用,扩大了硝磺草酮的杀草谱,提高防效7～10个百分点;混配施药还减少了烟嘧磺隆的用量,降低了玉米药害,增强了玉米生产的安全性.     

4种酰胺类除草剂对玉米的安全性及药效

室内外测定了4种酰胺类除草剂对玉米安全性及药效。结果表明 :异丙甲草胺与异丙草胺对玉米安全性最高 ,甲草胺次之 ,乙草胺对玉米苗期有药害。田间测产证明异丙甲草胺与异丙草胺对玉米增产明显 ,而乙草胺同人工除草对比略有减产。田间药效表明乙草胺对杂草防除效果最高     

烟嘧磺隆与氰草津混用对玉米田杂草的防效及安全性研究

烟嘧磺隆与氰草津混用防除玉米田杂草有显著的增效作用。4％烟嘧磺隆30g／hm^2与4％氰草津300g／hm^2、450g／hm^2、600g／hm^2混用后15d和30d,对玉米田杂草的株防效均在90％以上。但在施药初期玉米下部叶片有黄化、枯死等药害症状。室内试验表明,烟嘧磺隆和氰草津混用对玉米的根长、株高和鲜重均有一定的抑制作用,二者联合作用为相加或拈抗作用。     

代谢酶抑制剂PX对除草剂防除稗草的增效作用

为解决除草剂防除困难的问题,采用室内盆栽试验测定了PX、PM和Mn²⁺三种代谢酶抑制剂对精喹禾灵、莠去津、烟嘧磺隆、硝磺草酮和烯禾啶防除稗草Echinochloa crus-galli的增效作用,测定不同用量代谢酶抑制剂PX对这5种除草剂的增效作用及其与莠去津混用后稗草体内谷胱甘肽转移酶（glutathione S-transferase,GST）和细胞色素 P450（cytochrome P450,CYP450）活性的变化。结果显示,在3种代谢酶抑制剂中,代谢酶抑制剂PX对精喹禾灵、莠去津、烟嘧磺隆、硝磺草酮和烯禾啶5种除草剂的增效作用最显著。不同用量代谢酶抑制剂PX对不同除草剂的增效作用不同,其中75 g (a.i.)/hm²代谢酶抑制剂PX对莠去津的增效最佳,株防除效果和鲜重防除效果分别增加了35.33个百分点和37.33个百分点。莠去津与代谢酶抑制剂PX混用后,稗草体内GST和CYP450活性均较对照显著降低。表明除草剂与代谢酶抑制剂PX混用能增加除草剂对稗草的防除效果,可以达到减施除草剂的目的。     

农药悬乳体系流变学特性研究

研究了两种悬浮稳定剂对40%乙草胺+莠去津+氰草津悬乳剂的流变学特性的影响,发现在该悬乳体系中结合使用无机膨润土和有机黄原胶能增加体系的触变性能和稳定性能,能显著增加体系的粘度、屈服值和稳定度。     

九种除草剂对玉米田杂草的防除效果及其安全性评价

为明确9种常用除草剂对玉米田杂草的防除效果及其安全性。在福建省甜玉米制种田,采用茎叶喷雾法开展了9种除草剂在推荐剂量下的田间药效试验,并测定了除草剂对甜玉米及其后茬花椰菜和萝卜的安全性。结果表明,施药后25 d,9种除草剂的杂草株防效和鲜重防效均在92%以上;施药后50 d,27%烟 ? 硝 ? 莠去津可分散油悬浮剂[有效成分(下同) 810 g/hm2 ] 和25%硝磺 ? 莠去津可分散油悬浮剂 (750 g/hm2 ) 处理的杂草防除效果最好,以20%氯氟吡氧乙酸乳油 (180 g/hm2 ) 处理的杂草防除效果最差,杂草覆盖表现为重度。供试的9种除草剂对甜玉米生长安全,无明显药害症状,且部分药剂有明显的增产效果,其中以25%硝磺 ? 莠去津可分散油悬浮剂、20%烟嘧 ? 辛酰溴苯腈可分散油悬浮剂 (300 g/hm2 )、80%莠去津可湿性粉剂 (1 440 g/hm2 ) 和27%烟 ? 硝 ? 莠去津可分散油悬浮剂处理的玉米产量较高,与对照相比,增产率分别为21.03%、19.26%、18.74%和16.84%。10%硝磺草酮悬浮剂 (150 g/hm2 )、27%烟 ? 硝 ? 莠去津可分散油悬浮剂、33.5%硝磺 ? 异丙草胺 ? 莠去津悬浮剂 (1 005 g/hm2 ) 和30%苯唑草酮悬浮剂 (27 g/hm2 ) 处理对后茬花椰菜和萝卜均有较好的增产效果,增产率分别为18.05%和13.68%、3.37%和12.67%、15.45%和11.06%、8.21%和11.67%,但40 g/L烟嘧磺隆可分散油悬浮剂 (60 g/hm2 ) 对后茬花椰菜和萝卜的生长有抑制作用,与清水对照相比,分别减产9.74%和3.57%。研究结果可为甜玉米田杂草防除有效药剂的合理选择和应用提供科学依据。     

The effect of atrazine,cyanazine and cyprazine on photosynthesis and growth of nine grasses*

A semi-open circuit system for measuring changes in net CO₂ exchange (NCE) in single leaves of intact grasses following herbicide treatment is described and evaluated. There were significant differences in levels of inhibition and subsequent recovery of NCE in maize and eight weedy panicoid grasses following limited root uptake of atrazine (2-chloro-4-ethyl-amino-6-isopropylamino-1,3,5-triazine). cyanazine [2-chloro-4-(1-cyano-1-methylethylamino)-6-ethylamino-1,3,5-triazine] and cyprazine (2-chloro-4-cyclopropylamino-6-isopropyl-amino-1,3.5-triazine). Rate of NCE recovery was positively correlated (P = 0.05) with growth of seedlings in nutrient solution containing the herbicides. Rates of NCE recovery >0.9 mg CO2 per dm2 per h/h reflected rapid rates of herbicide detoxification in the leaves and a significant tolerance to preplant incorporated and postemergence applications of atra-zine, cyanazine and cyprazine. In contrast, some species, e.g. large crabgrass [Digitaria sanguinalis (L.) Scop.] and proso millet (Panicum miliaceum L.) treated with cyanazine demonstrated considerable tolerance to these treatments in spite of low NCE recovery rates indicating that factors other than foliar detoxification may play an important role in the tolerance of some grasses to 2-chloro- 1,3,5-triazine herbicides.     

Assessment of Chemical and Manual Weed Control Approaches for Effective Weed Suppression and Maize Productivity Enhancement Under Maize-Wheat Cropping System

Effective weed management in maize-wheat (M-W) cropping systems are accountable for higher yield and plant biomass. The objective of this study was to evaluate the effectiveness of manual weeding and chemicals (pre- and post-emergence herbicide) for actual weed control to enhance maize yield and M?W system productivity. Herbicides were treated as pre-emergence (sole), post-emergence (sole) and its combined application (pre- and post-emergence) for weed eradication and suppression. Sole pre-emergence herbicide (acetyclour?+?atrazine) and sole post-emergence herbicides (nicosulfuron), and its mixed application were used in the experiments. The experiment was comprised on 6 treatments with one weedy check or control plot: W1?=?weedy check, W2?=?acetyclour?+?atrazine, W3?=?atrazine, W4?=?nicosulfuron, W5?=?nicosulfuron?+?atrazine, W6?=?acetyclour?+?atrazine?+?nicosulfuron and W7?=?manual weeding. Main weeds were Cyperus rotundus, Tribulus terrestris, Dactyloctenium aegyptium and Cynodon dactylon. Experiential findings revealed that manual weeding was found most effective in terms of controlling weed and suppression. Among the herbicides application, promising results in terms of weed destruction and suppression were shown by combined application of acetyclour?+?atrazine?+?nicosulfuron which effectively controlled weeds as compared to other treatments. It was concluded that manual weeding drastically reduced weeds frequency and biomass while among the herbicides application acetyclour?+?atrazine and nicosulfuron could be promising for weeds suppression and clamp downing as compared to all other treatments under M?W cropping system.

     

土壤中烟嘧磺隆和莠去津残留对甘薯的药害评价

为了明确玉米田除草剂烟嘧磺隆和莠去津土壤残留对后茬作物甘薯生长的影响,于2017年分别在河北省保定满城区、文安县、霸州市和石家庄藁城区采集甘薯田土壤样品,采用QuEChERS法,结合超高效液相色谱-串联质谱法(UPLC-MS/MS)测定了土壤中烟嘧磺隆和莠去津的残留量;通过盆栽试验,测定了烟嘧磺隆、莠去津以及二者混用对...     

Transport to ground‐water of six commonly used herbicides: a prediction for two Italian scenarios

In Italy suitable standard scenarios for pesticide risk assessment based on computer models are lacking. In this paper we examine the use of the VARLEACH model to assess the potential danger of ground‐water pollution by six herbicides (alachlor, atrazine, cyanazine, linuron, simazine and terbuthylazine) which are used to protect irrigated (maize) and non‐irrigated (sorghum) crops in the Po Plain, one of the most important agricultural lands in Italy. Two extreme scenarios are taken: real worst case (sandy soil) and real best case (clay loam soil). The simulation suggests that cyanazine, linuron and terbuthylazine can be safely used in clay loam soil in both non‐irrigated and irrigated crops, while alachlor, atrazine and simazine can be safely used only in non‐irrigated crops. On the other hand, the application of all the herbicides tested should be avoided in sandy soil, with the exception of linuron in non‐irrigated crops. © 2000 Society of Chemical Industry     

烟嘧·莠去津不同剂型对后茬作物幼苗的影响

通过水培法研究了4种不同烟嘧磺隆·莠去津的剂型(20%烟嘧磺隆.莠去津可分散油悬浮剂、22%烟嘧磺隆.莠去津油悬浮剂、23%烟嘧磺隆.莠去津悬浮剂、79%烟嘧磺隆.莠去津水分散粒剂)对后茬作物幼苗生长的影响。结果表明,烟嘧磺隆.莠去津的不同剂型对于油菜和萝卜主根伸长的影响较大,在浓度仅为10mg/L时,对后茬作物就具有抑制作用;而对油菜和萝卜的芽长则影响较小,当药剂浓度大于80 mg/L才对后茬作物有影响;而对于小麦,可分散油悬浮剂对小麦的主根伸长和芽长的影响较大,而其他3个剂型的影响相对较小。     

TRIAZINE HERBICIDES ON MAIZE AND THEIR RESIDUAL EFFECTS ON FOLLOWING CROPS*

Summary. Pre-emergence application of 2–5 kg/ha (a.i.) of atrazine or simazine was the most effective treatment for control of broad-leaved weeds in maize. Other triazines injured maize at all rates tested. Among the crops following maize treated with atrazine or simazine at 2–5 kg/ha, sugar beet was injured whereas wheat, oats, vetch, onions and soybeans were not. Post-emergence application of triazine herbicides was not effective and did not increase maize yields significantly over those of the unweeded plots. Wheat, oats, vetch and sugar beet were injured when following maize treated with post-emergence sprays; onions and soybeans showed no visible injury except from atrazine or simazine at 5 kg/ha or more, and from mixtures of atrazine+prometryne or atrazine+ametryne at 12–5 kg/ha. Les triazines herbicides sur le mais et leurs arrière-effets sur les cultures suivantes     

Evaluation of herbicides for maize production in three ecological zones of Nigeria

Abstract

Maize cultivation in Nigeria has increased rapidly in the last few years as fertilizers have become more readily available to farmers. Without the use of herbicides however, the area of land that can be brought under maize production will be limited. The following herbicides were evaluated in three ecological zones of Nigeria: atrazine and mixtures of atrazine and simazine, atrazine and metolachlor and atrazine and cyanazine. All herbicide treatments were applied at the rate of either 1.0 or 2.0 kg a.i./ha. The plots that received 1.0 kg a.i./ha also received one supplementary hand weeding. All treatments gave yields comparable to the weed free control, with the exception of the unweeded higher rate of the atrazine and cyanazine treatment which gave the lowest grain yield as a result of poor weed control.