Effects of isothiocyanates on purple (Cyperus rotundus L.) and yellow nutsedge (Cyperus esculentus L.)     

JASON K. NORSWORTHY  MAYANK S. MALIK  PRASHANT JHA  MARCOS J. OLIVEIRA 《Weed Biology and Management》2006,6(3):131-138

Purple and yellow nutsedge are two of the most troublesome weeds in the world. In the south-eastern USA, both weeds are common in vegetable crops and are the most difficult weeds to control in this region. A greenhouse experiment was conducted to evaluate the herbicidal activity of five liquid isothiocyanates (ITCs) (benzoyl, o -tolyl, m -tolyl, tert -octyl, and 3-fluorophenyl) on purple and yellow nutsedge. All ITCs were applied to soil in jars at 0, 100, 1000, 5000, and 10 000 nmol g⁻¹ of soil and sealed for 72 h to prevent gaseous losses, followed by nutsedge growth evaluations after an additional 18 days. All ITCs reduced purple and yellow nutsedge shoot density and shoot biomass over the concentrations evaluated, with differences in the effectiveness on each species apparent among the compounds. Based on the lethal concentration values for shoot density, all ITCs were more effective in suppressing purple nutsedge than yellow nutsedge. Benzoyl and 3-fluorophenyl were generally the most effective of the five ITCs evaluated.  相似文献   

Characterization of propargyl bromide transformation in soil     

Papiernik SK  Gan J  Yates SR 《Pest management science》2002,58(10):1055-1062

Propargyl bromide is being investigated for its potential as a soil fumigant. Characterization of the fate of propargyl bromide in soil is important in determining both efficacy and the threat of environmental contamination. These experiments investigated some of the factors affecting the rate of propargyl bromide degradation in soil and quantified some of the products formed as a result of propargyl bromide degradation in four soils of differing composition and at three initial propargyl bromide concentrations. In all soils at all initial propargyl bromide concentrations, equimolar formation of Br- was observed during propargyl bromide degradation, but little propargyl alcohol (product of hydrolysis) was formed. The apparent first-order degradation coefficient (k) increased with decreasing initial propargyl bromide concentration in all soils, but the mass degraded per unit time increased with increasing propargyl bromide concentration. The rate of propargyl bromide degradation increased with increasing soil organic matter content, and the k value was correlated to the organic carbon content of the soil (correlation coefficient > 0.97 for all concentrations). Repeated application of propargyl bromide did not increase the rate of propargyl bromide degradation in soil. Addition of Br- did not affect the rate of propargyl bromide transformation in soil, so accumulation of Br- in the soil is not expected to impede propargyl bromide degradation.  相似文献   

帐幕熏蒸中溴甲烷气体浓度变化规律及检测标准的研究   总被引：2，自引：1，他引：1  

黄庆林  高崇省 《植物检疫》1998,12(6):321-325

采用科学的熏蒸剂检测方法,通过系统的浓度检测和分析,对口岸实际熏蒸中有代表性的３种地面条件熏蒸帐幕的气密性进行了比较,基本摸清了２５～３２℃温度条件下帐幕熏蒸中溴甲烷气体浓度的变化规律。结合试验研究结果,提出了可供熏蒸现场监管采用的浓度检测标准,并对帐幕熏蒸的部分技术性问题进行了探讨。  相似文献   

木质包装松材线虫溴甲烷熏蒸处理   总被引：8，自引：0，他引：8       下载免费PDF全文

贺水山  徐瑛  陈先锋  刘永胜  傅冬良 《植物保护学报》2005,32(3):314-318

为寻求一定温度下溴甲烷熏蒸处理杀灭木质包装中松材线虫的有效浓度和时间,给国际贸易中木质包装松材线虫的熏蒸处理提供科学依据,进行了木质包装松材线虫溴甲烷熏蒸处理研究.研究分实验室基础试验和集装箱应用试验两部分,先在实验室中筛选出熏蒸有效浓度和时间,再于集装箱中进行应用试验.结果表明:11～15、16～20、≥21℃时,溴甲烷剂量分别为64、56、48g/m3,熏蒸24h,24h时浓度分别不低于32、28、24g/m3,即CT值分别为1152、1008、864 gh/m3,能够100%杀灭木质包装中松材线虫的成虫、幼虫及卵.此外,证实了国际植物检疫措施标准ISPM NO.15<国际贸易中木质包装材料控制准则>中熏蒸处理的要求偏低,不能完全杀灭木质包装中松材线虫.  相似文献   

溴甲烷熏蒸处理鲜切花及其害虫的试验   总被引：1，自引：4，他引：1  

丁元明  王龙文  刘忠善  骆瑞方  彭昆伟 《植物检疫》2003,17(4):202-206

使用溴甲烷对16种切花及主要携带的南美斑潜蝇、棉蚜、二斑叶螨及花蓟马等害虫进行熏蒸试验。结果表明：如仅带有蚜虫或蓟马，所有供试切花均可进行熏蒸处理；如带有叶螨或斑潜蝇，金鱼草、菊花和孔雀草不宜熏蒸，玫瑰、勿忘我、康乃馨、百合、马蹄莲、情人草、非洲菊、剑兰和石斛兰可以熏蒸，满天星、天堂鸟、橙菠萝和紫罗兰在21℃下以36g/m^3，1．5h处理，对品质有轻度影响，但可100％杀死叶螨及斑潜蝇的成虫、幼虫和蛹。由于斑潜蝇卵的耐药性比其它虫态要强，对带有斑潜蝇卵而耐药性较差的切花，可以在采收后于室温下放置1～3天，待卵孵化后再进行熏蒸处理。  相似文献   

硫酰氟——溴甲烷土壤消毒潜在的替代品   总被引：4，自引：1，他引：4  

曹坳程  褚世海  郭美霞  段霞瑜  袁会珠  齐淑华 《农药学学报》2002,4(3):91-93

初步试验表明,硫酰氟25~50 g/m2对土壤真菌(Fusarium sp.)、线虫均有良好的杀灭效果,防治后番茄产量与使用溴甲烷50 g/m2相当。硫酰氟蒸汽压高,穿透性强,可杀死深土层中的线虫及病原菌。由于其在常温下是气体,即使在冬天使用,也不需要搭小拱棚或采用"热法"施药,因此比使用溴甲烷更为方便;使用时也不像威百亩那样需要专用的施药设备。因此,硫酰氟是溴甲烷土壤消毒很有前景的替代品。  相似文献   

Allium spp thiosulfinates as substitute fumigants for methyl bromide     

Jacques Auger  Frderic Cadoux  Eric Thibout 《Pest management science》1999,55(2):200-202

Methyl bromide, the most widely used fumigant, is considered to be one of the major factors causing depletion of the ozone layer, and this is likely to lead to it being banned in the near future. Allium sulfur volatiles (thiosulfinates, R-S-SO-R′; R, R′=Me, Pr, y Allul), known to be nematicides, have been evaluated as insecticides against insect pests in stored products, in comparison with their degradation compounds (disulfides) which have already been tested. Methyl and allyl thiosulfinates, with 24-h LD₅₀ values of 0.02–0.25 mg litre⁻¹, were more active than disulfides against six test insects and were superior to methyl bromide; it is suggested that they could be used as alternatives to methyl bromide in stored product control. ©1999 Society of Chemical Industry  相似文献   

老参地、农田地连续移栽人参实验研究   总被引：5，自引：0，他引：5  

曹志强  金慧  许永华  宋心东  娄子恒  张引  杨文志  曹立军  潘晓鹏  李培元  庞立杰  张达正  孙涛 《人参研究》2005,17(1):9-14

和大多数植物一样,人参存在着难以解决的不能重茬和连作的问题,笔者通过土壤杀菌、土壤复菌、在土壤中增加微量元素等综合性处理试验,找到了解决问题的关键,本文介绍老参地、农田地移栽人参的研究结果。  相似文献   

蔬菜大棚常用土壤消毒剂   总被引：1，自引：0，他引：1  

翟建华  曹晓妹  王蓓  刘向欣 《北方园艺》2009,(1)

对蔬菜大棚常用的几种土壤消毒药荆的性能、使用方法、应用领域、消毒机理及各自的特点进行了阐述.介绍了几种可以取代溴甲烷的土壤消毒剂,指出了今后用于蔬菜大棚的土壤消毒剂的发展趋势.今后土壤消毒荆的开发应朝着安全、高效、环境友好、使用方便的方向发展,以适应不同农业种植的各种要求.  相似文献   

冷水性鱼类工厂化养殖中臭氧催化氧化降解氨氮   总被引：12，自引：0，他引：12       下载免费PDF全文

刘永  曹广斌  蒋树义  韩士成  陈中祥 《中国水产科学》2005,12(6):790-795

研究低温下臭氧催化氧化降解养殖水体氨氮的有效途径，并对降解过程中产生的反应副产物进行分析。利用臭氧发生器和催化反应设备，把加入5mg／L NaBr的养殖水体与臭氧充分混合，在Br^-的催化作用下，使臭氧与氨氮产生氧化反应，产生氮气，达到去除氨氮的目的。实验在一个9．2m^3水体、养殖密度为10kg／m^3的封闭循环式冷水鱼养殖系统中，以虹鳟（Oncorhynchus mykiss）为实验动物，在192h的换水周期内，每24小时采水样1次，检测养殖水体中的pH、溶解氧、氨氮、硝酸盐、亚硝酸盐、悬浮物等水质指标，确定低温下臭氧催化氧化降解养殖水体氨氮的能力和使用方法。研究表明，在Br^-的催化作用下臭氧可有效氧化降解养殖水体的氨氮，降解效率可达50．11％，比臭氧直接氧化法高24．31％；降解过程中硝酸盐、亚硝酸盐都有一定积累，但在臭氧的作用下亚硝酸能转化为硝酸盐，亚硝酸盐含量在192h降至0．089mg／L，硝酸盐为主要副产物；pH值逐渐下降，192h降至5．55，养殖过程中可用NaOH-NaHCO3缓冲液进行适当调节。臭氧催化氧化降解氨氮是一种有效的水处理方式，对于冷水性鱼类工厂化养殖的循环水体处理具有重要的实用价值。  相似文献