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1.
K. L. S. Harley 《国际虫害防治杂志》2013,59(4):433-437
Abstract Experiments conducted at the International Rice Research Institute (IRRI) in the Philippines, showed that all commonly marketed formulations and derivatives of 2,4-D and MCPA were equally effective in controlling barnyard grass [Echinochloa crusgalli (L.) Beauv.] and other annual weeds in transplanted rice (Oryza sativa L). In the Philippines, these phenoxy acid herbicides cost US$2.50/ha as liquid formulations and US$5.50/ha as granular formulations. These low-cost herbicides provide excellent alternatives to hand weeding in transplanted tropical rice. Other herbicides which can control weeds before or after the weeds emerge are more expensive than 2,4-D or MCPA. Some of these selective herbicides, such as butachlor and TCE-styrene + 2,4-D, are in the Philippine market. Their prices vary from US$8 to US$12/ha. For direct-seeded flooded rice, granular formulations of several new herbicides, such as butachlor, benthio-carb and C-288 (chemistry not yet disclosed), were highly selective in controlling barnyardgrass and other annual weeds under tropical conditions. C-288 controls algae in addition to annual weeds in direct-seeded flooded rice. Of these three promising herbicides, only butachlor is marketed in the Philippines at US$8/ha. For upland rice, the chemicals which look promising are butachlor, benthiocarb and fluorodifen. Butachlor liquid is available to rice farmers in Asia at about US$16/ha. These herbicides provide an excellent alternative to hand weeding. Generally a complete job of weed control in upland rice requires more than one hand weeding. 相似文献
2.
Summary. Granular formulations of several new herbicides were tested for control of weeds in direct-seeded tropical rice. S -(4-chlorobenzyl)- N N -diethylthiolcarbamate (benthiocarb) and N -(butoxymethyl)-2-chloro-2',6'-diethylacetanilide (CP 53619) showed a high degree of selectivity between rice and weed seedlings. Applied 6 days after seeding, when grass weeds were at the 1-2-leaf stage, both herbicides gave excellent control of Echinochloa crus-galli and other weeds, and caused little or no damage to rice cv. IR22. 相似文献
3.
Abstract Seven new granular herbicides were evaluated in Taiwan for the control of weeds in broadcast flooded rice. In general, herbicides applied early (6 days after seeding) gave better weed control but caused more crop damage than when applied late (12 days after seeding). Benthiocarb applied at 6 days after seeding, when most weeds were at the one to two leaf stage, was highly selective in controlling broad-leaved weeds and sedges with no sustained injury to rice. Butachlor failed to control broad-leaved weeds at the two to three leaf stage. The initial toxicities of C-288 (dimethatryn plus piperophos, 1:4) piperophos (C-19490), and CRD 71.6388 were too severe to warrant their use in direct-seeded flooded rice in Taiwan. Among the herbicides tested, thiochlormethyl and molinate and thiochlormethyl when applied late, were the most selective. When applied 12 days after seeding or at the three to four leaf stage of weeds, both treatments provided excellent control of weeds without causing any crop injury. 相似文献
4.
Abstract Further work with the herbicide C 19490 (S-(2-methyl-1-piperidyl-carbonylmethyl)-O,O-di-N-propyl dithiophosphate) in the mixture C 288 with the triazine C 18898 in the ratio 4:1, and with 2,4-D isopropyl ester (2,4-D IPE) in the ratios 2:1 and 3:2 have been completed. New toxicological data show that the risk of toxicity hazards to the user or to other mammals by contamination is low. Residue work shows that C 19490 leaves very low or undetectable residues in rice grain and soil, though C 18898 was detected in both, but never at more than 0.28 ppm in soil or more than 0.04 ppm in grain. There was no interaction between either C 19490 or C 288 and commonly used insecticides. Uptake of the products by plants was shown to be preferentially through emerging shoots, and less through roots. Field trials resulted in recommendations for around 2 kg C 288 total a.i./ha in Japan, optimum timing depending on the prevailing temperature. Successful control was achieved in Taiwan with C 288 at 1 kg a.i./ha in both the cool and warm season crops, applied 7–12 days after transplanting. In equatorial Asia, mixtures worked well: C 288 at 0.75–1.25 kg a.i./ha, C 19490 at 0.75–1.0 + 2,4-D IPE at 0.5 kg a.i./ha and the 3:2 mixture at 0.75 + 0.5 kg a.i./ha (granular), applied four DAT on dense weed stands, but up to ten DAT on stands comprising predominantly moderate infestations of Echinochloa crusgalli, Monochoria vaginalis and annual Cyperus spp. These recommendations resulted in yields which were never significantly different from those of hand-weeded areas. On light, permeable soils, e.g. in Pakistan, C 288 at 1.0–1.25 kg a.i./ha, 8–10 DAT was less harmful to the crop than lower rates applied earlier, and was better than the 2,4-D IPE mixture for weed control. In Egypt, C 19490 + 2,4-D IPE at only 0.375 + 0.25 kg a.i./ha was successful, because of the susceptible weed flora. 相似文献
5.
5种除草剂防除旱直播稻田杂草比较试验 总被引：3，自引：0，他引：3
42%噁草·丁草胺EC1 500 mL/hm2对鳢肠的防效为82%,对禾本科杂草、大多数阔叶杂草及莎草均有良好的防除效果,防效均达100%;33%二甲戊灵EC 2 250 mL/hm2对旱莲草的防效为64.7%,对禾本科杂草和部分阔叶杂草及莎草的防效均在86%～100%之间;30%苄·丁WP2 250 g/hm2和35%苄嘧.丙草胺WP 900 g/hm2对阔叶杂草和莎草科杂草的防效较好,但对禾本科杂草的防效较差;30%丙草胺EC1 800 mL/hm2对稻田多种杂草的防效均低于63%。 相似文献
6.
大豆除草剂对2种丛枝菌根的影响 总被引：2，自引：0，他引：2
在接种Glomus intraradices和Glomus mosseae的大豆植株盆栽钵中,按大田常规用量,施用乙草胺、丁草胺、灵达、骠马和精喹(禾灵)5种除草剂,显著减少了大豆植株的生物量和土壤中AM真菌菌丝的总量,降低了丛枝菌根(arbuscular mycor-rhiza,AM)真菌侵染率、菌丝碱性磷酸酶(alkaline phosphatase,ALP)和琥珀酸脱氢酶(succinate dehydrogenase,SDH)活性。处理6周后,显著降低大豆植株生物量的除草剂为乙草胺和丁草胺,植株生物量前者为12.6、14.5 g,后者为12.7和15.5 g,影响较小的为精喹(禾灵)(植株生物量各为20.8、23.5 g),而对照的生物量为29.5、30.8 g;显著减少AM真菌侵染率的除草剂为丁草胺(AM真菌侵染率为17.4%、24.1%),影响较小的为乙草胺和灵达(前者为29.3%、30.7%,后者为26.3%和32.2%),而对照侵染率为78.5%、62.4%;显著降低AM真菌菌丝ALP和SDH酶活性的除草剂为丁草胺(ALP为10.2%、13.6%,SDH为13.5%、18.8%),影响较小的为乙草胺和灵达(前者ALP为15.7%、17.4%,后者为13.9%、17.8%,SDH前者为22.4%、23.5%,后者为19.8%、25.0%),而对照的ALP为47.0%、36.3%,SDH为62.7%、48.4%;此外,除草剂也使土壤中AM真菌菌丝的总量显著减少。 相似文献
7.
The four main wild rice species are: Oryza rufipogon Griff, embracing a wide range of “red rice” types closely related to O. sativa L.; O. longistaminata Chev. & Roehr, a rhizomatous perennial; O. barthii Chev. the annual wild rice of West Africa; and O. punctata Kotschy ex Steud, a small seeded annual. The distribution and importance of these species are discussed in relation to the different systems of rice growing. Annual wild rice problems are favoured by dry sowing followed by flooding. For cultural control, soil puddling and direct sowing into water are recommended. In a series of pot experiments with O. punctata and rice, 18 herbicides were shown to be at least partially selective, including: alachlor, butachlor, S-4-chlorobenzyl diethyldithiocarbamate (B-3015), 4-(2,6-dichlorobenzyloxymethyl)-4-ethyl-2,2-dimethyl-1,3-dioxolan (WL 29226), 3-(α α-dimethylbenzyl)-1-methyl-1-phenylurea (K 1441), isoproturon, metamitron, molinate and perfluidone. B-3015 was the most selective of these but the selectivity of alachlor and molinate could be greatly increased and became comparable to B-3015 when the crop seed was dressed with the protectant 1,8-naphthalic anhydride (NA). Other herbicides for which NA provided a protective effect were: butachlor, metolachlor (CGA 24705), epronaz, ethofumesate, perfluidone and 4,4,4-trichloro-2-phenylbut-1-ene (Dowco 221). 相似文献
8.
Bioconcentration kinetics of three major paddy-field herbicides, butachlor, thiobencarb and chlomethoxyfen were investigated by accumulation and elimination measurements in laboratory experiments with black silver carp (Aristichthys nobilis). The biological half-lives of the three herbicides on exposure at high and low concentrations were 11·6 and 23·1 days for butachlor, 13·9 and 17·3 days for thiobencarb and 5·6 and 4·5 h for chlomethoxyfen, respectively. One- and two-compartment models were used to elucidate the bioconcentration kinetics. Data from a short-term, 14-day expiry experiment were used to estimate the parameters in the models by non-linear regression analysis, and the bioconcentration factors (BCF) in the steady state were calculated from those parameters. The BCF in the steady state have the descending order thiobencarb > chlomethoxyfen > butachlor at high concentration, and butachlor > thiobencarb > chlomethoxyfen at low concentration. One-compartment model for butachlor and thiobencarb and a two-compartment model for chlomethoxyfen are useful to predict the BCF on prolonged exposure and, further, to assess the influence of these pollutants. © 1997 SCI. 相似文献
9.
Field studies were undertaken to explore the weed management strategies for transplanted and direct wet-seeded rice in the Dera Ismail Khan district of North-west Frontier Province, Pakistan. The experimental design was a randomized complete block with a split plot arrangement. The main plots consisted of two planting techniques (transplantation and direct seeding), while weed control practises assigned to the subplots included the use of the granular herbicide Sunstar 15WG (ethoxy sulfuron), Machete 60EC (butachlor), conventional hand weeding, and the weedy check (untreated control). Data were recorded on weed dynamics and the agronomic parameters of the rice crop. Economic analyses on the data were also run. The weed density and biomass were lower in the transplantation plots than the direct-seeding plots. The herbicides ethoxy sulfuron and butachlor reduced the density over the weedy check, with a density comparable to hand weeding in 2002, but slightly higher in 2003. As a result of weed management by hand weeding and herbicides, the paddy yield and its components were significantly higher for the transplanted method compared to the direct-seeded method. The comparable yield of herbicides with hand weeding offers an option for the use of herbicides as an alternative management tool. In light of our findings, it is concluded that for good economic returns, rice crops may be transplanted rather than direct-seeded. The herbicides ethoxy sulfuron and butachlor offer a weed control cover comparable with hand weeding under the transplantation method, while butachlor is good for controlling weeds even under the direct-seeded conditions in the agroclimatic conditions of the area. 相似文献
10.
基于登记用量分析我国四大主粮作物田除草剂的登记现状 总被引：1，自引：0，他引：1
为除草剂合理减施提供数据参考，本研究于2019年7月3日自中国农药信息网查询我国四大主粮作物——小麦、水稻、玉米和马铃薯登记的除草剂，并对这4种作物田登记除草剂单剂（含原药）及混剂的条目数量进行整体分析，并对所有单剂有效成分以及不同剂型的登记条目数量进行分析，筛选出高用量单剂有效成分，分别从剂型和防治对象上进行用量分析，再将用量最高的4种有效成分、3种作物和3种防治对象进行组合，对已登记的组合进行用量分析。结果显示：有效成分用量最大值、均值和范围排序均依次为水稻田、小麦田、玉米田和马铃薯田，并选出15种高用量单剂有效成分，其中2甲4氯钠、2，4-滴钠盐、苯磺隆、丙草胺、丁草胺、2，4-滴二甲胺盐和2甲4氯二甲胺盐等存在用量差异大、异常高值点多的问题；登记除草剂单剂有效成分用量最高的剂型为可溶粉剂，用量最高的防治对象为阔叶杂草和莎草科杂草；2甲4氯钠-水稻-阔叶杂草和2甲4氯钠-水稻-莎草科杂草组合用量差异大且离群高值点多，究其原因可能与剂型、厂家有关。为减少除草剂用量，建议在最低有效剂量研究基础上，选择有效成分用量较低的除草剂品种。 相似文献
11.
AbstractA study was carried out in sandy clay loam textured soil of Mymensingh, Bangladesh to evaluate weed control efficiency of pre-emergence herbicide pyrazosulfuron-ethyl either alone or in sequential application with post-emergence herbicide in transplanted rainy season rice under non-puddled strip-tilled (NPST) field condition and also to examine the residual effect of those herbicides on germination and growth of the subsequently grown wheat crop. Five treatment combinations of pyrazosulfuron-ethyl were tested against one weedy check and one weed-free check. The study revealed that NPST rice field was mostly infested by grass and sedge weeds and herbicide treatments offered a wide range of control (above 50% to 95%) on all types of weeds. Application of pyrazosulfuron-ethyl followed by (fb) orthosulfamuron fb butachlor plus propanil provided the most effective and economic weed control over two years of the study. Moreover, micro-plot bioassay study claimed germination and growth of subsequently grown wheat were not adversely affected by herbicides that were applied in rice. Therefore, application of pyrazosulfuron-ethyl followed by post-emergence herbicide could be effective and economic to control weeds in NPST rice under rice-wheat system, but proper rate and time of application should strictly be followed. 相似文献
12.
为实现水稻生产减施除草剂的目标,将化感材料与农艺措施相结合取得对稻田杂草有效控制的效果,田间采用再裂区试验法研究了化感稻3号和N两优201两个水稻化感材料和非化感材料五山丝苗在不同水分管理、移栽密度和除草剂不同用量下,对水稻产量和田间杂草生物量的影响。结果表明:无论早季稻田还是晚季稻田,施用常规除草剂量的小区杂草生物量均为0,施用常规剂量50%除草剂且仅在孕穗期晒田的小区和常规密度小区有少量杂草发生。不施除草剂的水稻材料小区杂草生物量依次为化感稻3号N两优201五山丝苗。移栽后75 d,不施除草剂的小区相同水稻材料孕穗期不晒田比晒田处理、高密度比常规密度处理的杂草生物量小。早季稻田不晒田和高密度提高了水稻的产量,晚季稻田则相反。化感材料化感稻3号和N两优201在田间的抑草效果较五山丝苗要好。在水稻生产中,水稻化感材料结合农艺措施,可以实现水稻不减产,田间杂草得到有效控制,除草剂量减50%的目标。 相似文献
13.
Metabolism and selectivity of rice herbicides in plants 总被引：1，自引：0，他引：1
Kenji Usui 《Weed Biology and Management》2001,1(3):137-146
Chemical weed control with effective and highly active herbicides has been very useful and convenient means. It has contributed to stable crop production and is labor saving. Recent herbicides have had characteristics such as high effectiveness without causing environmental pollution or harmful effects, and appropriate herbicides having high activity, low toxicity, high selectivity and being non-persistent have been developed. The metabolism of rice herbicides used mainly in Japan, such as sulfonylurea, chloroacetamide, acylamide, urea, thiocarbamate, pyrazole, triazine, diphenyl ether, phthalimide, phenoxy, aryloxyphenoxypropionate, etc., is reviewed, and its involvement in selectivity is also discussed. The metabolism of herbicides is closely related to their activity and selectivity. Differential herbicide metabolism in plants is a contributing factor of selectivity between crops and weeds. Chemicals that are more detoxified in crops and/or more activated or less detoxified in weeds are considered as being effective and selective herbicides. The metabolism of various types of rice herbicides includes: oxidative reaction (ring and chain hydroxylation, O - and N -dealkylation), hydrolysis and subsequent glucose conjugation, and glutathione conjugation in rice. These detoxicative activities are much higher in rice than weeds in paddies, and this leads to the selectivity of herbicides. Enzymes, oxidase, P-450 mono-oxygenase, esterase, acylamidase, glucosyl transferase, glutathione transferase, etc., play important roles in herbicide metabolism and selectivity. 相似文献
14.
Aurora M. Baltazar 《Weed Biology and Management》2017,17(2):57-67
Two major weeds in rice in the Philippines, Sphenochlea zeylanica Gaertn. and Echinochloa crus‐galli (L.) Beauv., are controlled with chemical and cultural methods. In the 1980s, after >10 years of continuous use of 2,4‐D, S. zeylanica evolved resistance to the chemical in those rice fields that had been treated with 2,4‐D once or twice every cropping season. In the 1990s, E. crus‐galli evolved resistance to butachlor and propanil in rice monocrop areas where both herbicides were used continuously for 7–9 years. Rice farmers continue to use 2,4‐D, butachlor and propanil extensively and are often unaware of herbicide resistance or the potential for cross‐resistance, its causes or its implications. In order to control herbicide‐resistant E. crus‐galli, farmers are shifting to locally available herbicides with different modes of action, such as bispyribac, an acetolactate synthase inhibitor, and cyhalofop, an acetyl coenzyme A carboxylase inhibitor. Follow‐up manual weeding or rotary weeding after herbicide spraying, a common farmers’ practice, removes the susceptible and resistant biotypes and could help to delay or prevent the evolution of resistance. Although the resistance mechanisms of both weeds are not determined yet, they could be related to enhanced degradation that is similar to the mechanisms that are shown by the resistant biotypes in other countries. 相似文献
15.
Siddall TL Ouse DG Benko ZL Garvin GM Jackson JL McQuiston JM Ricks MJ Thibault TD Turner JA Vanheertum JC Weimer MR 《Pest management science》2002,58(12):1175-1186
A novel series of substituted 3-phenyl benzoylpyrazoles were prepared and tested as potential grass herbicides. The targeted materials were prepared by three newly developed synthetic routes, which allowed a comprehensive study of the SAR (structure-activity relationships) of this series. The best combination of grass weed activity (Avena fatua L, Setaria viridis (L) Beauv and Alopecurus myosuroides Huds) and wheat selectivity was obtained with an alkoxy group in the 4-position of the phenyl ring. Activity was further enhanced by the presence of tert-butyl on the pyrazole and a methyl group at the C-2 position of the benzoyl moiety. The alkoxy-substituted 3-phenylbenzoylpyrazoles are a novel class of herbicides with potential utility for control of important grass weeds in cereals. 相似文献
16.
Ian M. Heap 《Pest management science》1997,51(3):235-243
The 1995/6 International Survey of Herbicide-Resistant Weeds recorded 183 herbicide-resistant weed biotypes (124 different species) in 42 countries. The increase in the number of new herbicide-resistant weeds has remained relatively constant since 1978, at an average of nine new cases per year worldwide. Whilst 61 weed species have evolved resistance to triazine herbicides, this figure now only accounts for one-third of all documented herbicide-resistant biotypes. Triazine-resistant weeds have been controlled successfully in many countries by the use of alternative herbicides. Due to the economic importance of ALS and ACCase inhibitor herbicides worldwide, and the ease with which weeds have evolved resistance to them, it is likely that ALS and ACCase inhibitor-resistant weeds will present farmers with greater problems in the next five years than triazine-resistant weeds have caused in the past 25 years. Thirty-three weed species have evolved resistance to ALS-inhibitor herbicides in 11 countries. ALS-inhibitor-resistant weeds are most problematic in cereal, corn/soybean and rice production. Thirteen weed species have evolved resistance to ACCase inhibitors, also in 11 countries. ACCase inhibitor resistance in Lolium and Avena spp. threatens cereal production in Australia, Canada, Chile, France, South Africa, Spain, the United Kingdom and the USA. Fourteen weed species have evolved resistance to urea herbicides. Isoproturon-resistant Phalaris minor infesting wheat fields in North West India and chlorotoluron-resistant Alopecurus myosuroides in Europe are of significant economic importance. Although 27 weed species have evolved resistance to bipyridilium herbicides, and 14 weed species have evolved resistance to synthetic auxins, the area infested and the availability of alternative herbicides have kept their impact minimal. The lack of alternative herbicides to control weeds with multiple herbicide resistance, such as Lolium rigidum and Alopecurus myosuroides, makes these the most challenging resistance problems. The recent discovery of glyphosate-resistant Lolium rigidum in Australia is a timely reminder that sound herbicide-resistant management strategies will remain important after the widespread adoption of glyphosate-resistant crops. ©1997 SCI 相似文献
17.
当前我国水稻田登记的除草剂活性成分组合共204种, 包括55种单剂和149种复配剂?在总结各种稻田除草剂应用技术要素的基础上, 提出稻田除草剂选用中具有普遍性的6个关键问题, 包括:水稻栽培方式?稻田除草剂施用时期?施用方法?稻田主要禾本科杂草种类?稻田非禾本科主要杂草类型?田间杂草生育期; 基于各种除草剂品种对应上述6个问题上的应用特点, 开发了“稻田除草剂选用参考系统”, 该手机软件共1.8 MB, 可以在安卓手机上安装使用?该软件可以根据用户在上述6个问题上的选项组合, 直接获得适用除草剂品种清单; 也可以根据用户输入除草剂名称所含字词, 检索相关的除草剂品种清单?此外, 软件中列出了每种除草剂的使用技术要点? 相似文献
18.
Two-way effects of herbicide on rice resistance and multiplication and feeding of the rice brown planthopper (BPH), Nilaparvata lugens (Stål) were studied. Four of 11 herbicides tested, butachlor, metolachlor, oxadiazon and bentazone, had significantly stimulating effects on multiplication and feeding of BPH. Multiplication times (N 1/N 0) of BPH on the rice treated with the four herbicides were 674, 367, 322 and 311, respectively, while that of N. lugens on the untreated plants was 159. The results of measurements of honeydew production by BPH indicated that the feeding rates of the brown planthoppers increased when the insects fed on the plants treated with bentazone, quinclorac, oxadiazon and quinclorac. Survival rates of N. lugens first to third-instars rose on the rice plants treated with butachlor, bentazone, but that of the fourth and fifth instars were not affected. Furthermore, all of those herbicides tested led to a decline of rice resistance, i.e. the injury scales of the treated plants were larger than that of the control under the same pest stress. Based on their effects on rice resistance and on BPH, the herbicides tested can be divided into two categories, one affecting rice resistance and BPH multiplication, the other affecting rice resistance only. 相似文献
19.
Abstract An ICI survey of the arable area of southern Brazil in 1971 confirmed the urgent need for some form of conservation tillage system for soyabean wheat primarily to control soil erosion. A practical system of no-tillage soyabean was developed for N. Parana, with weed control based on careful crop residue management and sprays of paraquat mixed with either linuron or metribuzin. The marked superiority of these mixtures over paraquat alone for the control of vigorous annual grasses was noted. This effect is, in part attributed to the capacity of metribuzin and linuron (along with other herbicides) to inhibit photosynthesis, thereby facilitating the translocation of paraquat. Where residual herbicides are not used, diuron at low rates in suitable formulation proved the best additive for paraquat. Problem broadleaved weeds are controlled by adding 2, 4-D to paraquat. Temperature, rainfall, the presence of fallows and the interval between harvest and the next planting, all affect pre-plant weed control for no-till soyabean. A key issue is to prevent excessive stands of weeds. Control within the crop can be provided by shielded, directed sprays of paraquat for which tractor mounted sprayers were developed. Recent discoveries of pre- and post-emergence selective herbicides provide improved and alternative in-crop weed control options. Crop diversification and further general no-till research show promise of further rational, chemical and cultural methods of weed control. 相似文献