莲田杂草防除技术

莲田杂草又称藕田杂草.由于莲藕是水生作物,莲田的杂草与稻田基本相似,但不能直接使用稻田的除草方法与技术,并且很多稻田的化学除草剂对莲苗有伤害,特别是对籽白莲的花蕾伤害很大.2000年我地一莲农采用25%精克草星防除莲田杂草,结果使1.33 hm2(20亩)白莲苗受害绝收.针对这一情况,2001年推广了以下几种莲田除草方法,取得很好效果,现介绍如下.     

第三章 正确使用除草剂及注意问题

一、合理使用除草剂,提高除草效果。化学除草的目的,就是防治杂草,保护作物,提高作物的产量和质量。为了提高防除杂草效果,除了应当了解除草剂本身应用的特殊性外,还应了解影响除草效果的因素,提高除草效果。(一)选择合适的除草剂种类每一种除草剂其作用机制,防治对象和除草效果是不同的,选择合适的除草剂,是提高除草效果的前提。如:氟乐灵只对杂草幼根和幼芽有抑制作用,对大草无效;对禾本科杂草效果好,对双子叶杂草效果就差一些,尤其对龙葵、荠菜效果不好,所以在应用氟乐灵时,     

第四章 蔬菜栽培与杂草的化学防除

在菜田生产中,蔬菜不论其种类、数量和种植方式,都比大田和果树等作物复杂得多,管理也比较精细。再加上菜田水肥条件好,杂草发生数量大,危害重,所以菜田化学除草应充分考虑蔬菜栽培中的特点。一、蔬菜栽培方式与化学除草1.以露地栽培化学除草为主。露地栽培和保护地栽培比较,化学除草的重点应放在露地栽培,因保护地栽培蔬菜绝大部分处于冷凉季节,栽培面积又小,部分杂草种子休眠,杂草发生量少,此时劳力还比较充     

正确认识化学除草的重要性

化学除草是农田草害综合防治中的重要手段之一,为降低农田杂草危害和保障作物安全生长发挥了重要作用。由于田间杂草具有种群数量大、适应性广、生命性广、生命力强的特点,给化学除草工作带来     

洋葱田化学除草技术

洋葱田中杂草长期与洋葱争光、争水、争养分,使洋葱大量减产,商品性降低。从1995年开始,我们在洋葱田进行化学除草技术研究。现综述如下:1　育苗田化学除草洋葱种皮较坚实,需浇足底水,才可促进出苗,然而这样也最有利于杂草的萌发生长,造成草荒。因此,在洋葱出苗前要及时进行化学除草。目前,对洋葱幼苗没有或基本没有危害、除草效果好的除草剂有33%除草通乳油、48%地乐胺乳油、50%扑草净可湿性粉剂等。这些除草剂主要防除一年生禾本科杂草,湿度大时兼治小粒种阔叶草。药效期以正常计算除草通50天,地乐胺40天,扑草净30天左右。基本上能控制整…     

北方落叶果园化学除草技术问题

杂草危害直接造成果树产量损失一般在20%左右,我国大型果园除草用工仅次于病虫害防治,约占果树作业总用工量的三分之一。有的果园全年除草4-5次,雨季还常出现草荒。化学除草比人工或机械除草有明显优越性,是现代化农业的主要标志。1979年以来我所开展化学除草试验研究,今对北方落叶果园的化学除草技术问题进行探讨。 一、重点防治的果园杂草种类 根据所内外的试验和调查,北方落叶果园的杂草种类超过100种,常见杂草有60余种。从数量说,一年生杂草最多,而多年生杂草发生时期长,可以无性繁殖和种子繁殖,有些是较难防除的恶性杂草,如白茅、香附…     

绿色无公害蔬菜管理措施

1清除田间杂草蔬菜生长过程中会出现杂草,禁止使用基因工程产品和化学除草剂除草,选择使用无公害方式除草。做好人工中耕除草,可清除行间杂草,防止杂草与蔬菜争夺养分。清除株间杂草,技术简单。对大面积绿色无公害蔬菜可采取机械除草。机械除草是利用除草机械对表土进行松土、断层等切断草根,使杂草断水,切断养分,禁止杂草生长,达到控制杂草目的。病虫害在蔬菜整个生长周期呈阶段性发生态势,降低蔬菜经济效益和食用价值。要重视病虫害管理,遵循预防为主、综合防治原则,选择具有抗虫能力的绿色无公害蔬菜种子。     

96%金都尔乳油防除番茄田杂草药效试验

蔬菜类作物化学药剂除草,多年来一直是适宜应用的农药品种少,能开展化学药剂除草的蔬菜除草剂种类有限,2004年为了解96%金都尔对番茄田杂草的防除效果及对番茄安全性,在番茄移栽田进行了96%金都尔乳油不同剂量除草效果及安全性的试验.     

杨树苗圃地化学除草技术要点

杂草对杨树扦插危害较大，尤其是窄叶杂草，往往会影响杨树的根系发育。而人工除草容易伤及苗木，并且费工、费时，还很难将杂草除尽。科学使用化学除草技术，有一定的持效期，可大大降低除草成本，且不伤根、不伤芽。     

蔬菜覆膜地化学除草小结

杂草,常在地膜与地面之间形成厚厚的一层草垫,使增产效能得不到充分的发挥,一般可减产5～15%以上。而且在地膜覆盖条件下,人工除草困难大,用工多。因此化学除草势在必行。几年来,我们用除草剂拉索、氟乐灵、除草醚,在地膜覆盖地上,对茄子、辣子、西红柿、菜瓜进行了试验、示范,效果较为理想。一、除草效果试验示范地杂草种类很多,常见杂草有20余种,其中危害最大的杂草有灰条、冰草、刺盖、苦苣     

几种除草剂在直播芹菜田的应用技术研究

为筛选适合芹菜直播田使用的除草剂,进行了3种除草剂在直播芹菜上的田间药效试验。试验结果表明．播种当天施药,各药剂的株防效均较好,但对芹菜成苗影响较大;播前3d施药,48％氟乐灵乳油表现出较好的安全性和除草效果,其中,120mL／667m2处理的成苗率接达96．42％,僵苗率仅0．04％,对禾本科杂草的株防效高达98．51％,对双子叶杂草的株防效接近70％;播前7d施药,3种药剂均表现出良好的安全性和除草效果,仅96％精一异丙甲草胺乳油各处理的安全性相对稍差。因此,直播芹菜田应用除草剂时,在播前3—7d用药较为合适。     

An evaluation of pre-emergent herbicides for container-grown ornamental plants

Two applications of 5 herbicides were evaluated during spring and summer for weed control and phytotoxicity on 25 species of trees, shrubs and herbaceous perennials. Weed control was considered to be effective if herbicide-treated pots contained at most 20% of the weeds in untreated pots. Oxyfluorfen applied at 1.25, 2.5 and 5.0 kg ha^?1 provided effective control of grass and broad-leaved weeds for 8 weeks after the first application, and the 2 higher rates effectively controlled all weeds for 12 weeks after the second application. Oxadiazon at 2.0, 4.0 and 8.0 kg ha^?1 effectively controlled all weeds for 8 weeks after the first application, but only the highest rate was effective 12 weeks after the second application. Napropamide at 5.0, 10.0 and 20.0 kg ha^?1 effectively controlled grasses for up to 12 weeks, but only effectively controlled broad-leaved weeds at the 2 higher rates for 8 weeks after the first application and failed to control them after the second application. Alachlor at 4.0, 8.0 and 16.0 kg ha^?1 and oryzalin + trifluralin at 0.5, 1.0 and 2.0 kg ha^?1 provided effective control of grasses for 8 weeks after the first application. These herbicides at the highest rate also controlled broad-leaved weeds for 8 weeks after the first application. However alachlor and oryzalin + trifluralin failed to provide effective control of any weeds after the second application.Competition from weeds reduced the shoot dry weight (SDW) of unweeded control pots by 20% compared with hand-weeded control pots. None of the herbicides produced visible clamage in any plants. The SDW of 8 species treated with some of the herbicides was significantly lower than the corresponding hand-weeded control plants, and for 6 of these species some herbicide treatments were identified as being possibly phytotoxic. Oxyfluorfen appeared to inhibit the growth of Photinia and Coleonema, and alachlor inhibited the growth of Photinia, Eriostemon, Azalea ‘Splendens’, Lavendula and Coleonema. Oryzalin + trifluralin appeared to inhibit the growth of Bauhinia, and napropamide and oxadiazon inhibited the growth of Coleonema.     

12种除草剂对苹果园杂草的杀灭效果

针对苹果幼树园杂草难以控制的问题,作者选用12种除草剂做除草效果试验。结果表明:百草枯杀灭杂草效果最好,在打药后当天就能把杂草全部杀死;其次为95%草甘膦铵盐、10%草甘膦、41%草甘膦异丙铵盐,在打药后14d能把杂草从根部彻底杀死;农基阔锄(10%乙羧氟草醚乳油)、新快锄(8.8%精喹禾灵)、莠去津3种除草剂在打药后28 d表现出杀灭杂草的作用;乙草胺、精喹禾灵、仲丁灵、拿捕净、施田扑与对照没有明显差异,杀灭杂草效果最差。     

不同甘蔗专用除草剂药效试验

5种除草剂试验结果表明，49％蔗安、30％蔗龙乐、80％蔗农乐、保蔗等药后14d，防效均达97％以上，且对甘蔗安全。因此，它们均可用作甘蔗苗后杂草处理剂，使用剂量以商品标准剂量即可。     

不同除草剂防除甜菜田杂草试验效果

为了筛选防除甜菜田杂草理想的除草剂,进行了3种除草剂（各设3种剂量）的甜菜田杂草防除试验,结果筛选出了适于本地区甜菜田使用的除草剂72%都尔用量为133～160mL/667m^2,96%金都尔用量为100～120mL/667m^2,33%施田补用量为334mL/667m^2。     

Landscape simplification promotes weed seed predation by carabid beetles (Coleoptera: Carabidae)

Weeds constitute major constraints for farmers by reducing crop yield and quality. However, weeds are managed effectively using herbicides, but this may cause harmful effects on human health and the environment. In an experiment on weed seed predation, we tested the biological control potential of carabid beetles to combat weeds in the absence of herbicides. Seeds from three common weed species were placed in cereal fields on conventional and organic farms located along a landscape complexity gradient (area annual crops within 1 km) in two distinct regions in Sweden. Carabid beetles were sampled in the same fields using pitfall traps. Neither carabid species richness nor seed removal was related to organic farming. Seed removal was significantly related to carabid species richness and both carabid species richness and seed removal was higher in landscapes with large total area of annual crops, although the evenness of the carabid communities was lower. The carabid genera with strongest positive relationship to seed removal differed between regions (Trechus in Uppland and Pterostichus in Scania), as did the preference for the different weed seed species. This study concludes that carabid species richness contributes to weed seed predation and that large scale landscape context explains more variation in the carabids’ responses than local farming practices.     

文冠果园中应用不同除草剂的效果

对9%莎草净、240 g/L果尔乙氧氟草醚、108 g/L高效氟吡甲禾灵、25%侨虎硝磺秀去津、250 g/L氟磺胺草醚、10.8%精喹禾灵6种除草剂在文冠果林园的除草效果进行比较试验。结果表明,以每666.7 m 2喷施240 g/L果尔乙氧氟草醚50 mL、25%侨虎硝磺秀去津200 mL、250 g/L氟磺胺草醚100 mL、10.8%精喹禾灵40 mL对杂草地上部分有不同程度的影响。240 g/L果尔乙氧氟草醚50 mL、25%侨虎硝磺秀去津200 mL、250 g/L氟磺胺草醚100 mL对文冠果叶片有一定影响。250 g/L氟磺胺草醚100 mL+10.8%精喹禾灵40 mL对杂草的消除实现了全覆盖,但对文冠果的叶片影响较大。实际操作中,须注意避开树体喷施。     

Evaluating weed control and response of newly planted peach trees to herbicides

ABSTRACT

Field experiments were conducted in North Carolina to determine peach response to herbicides. Mesotrione, rimsulfuron, and sulfentrazone did not injure newly planted peach trees. However, halosulfuron at the higher rate caused injury to peach trees, but did not reduce tree cross-sectional area or winter pruning weight. Another field experiment was conducted to determine the effect of herbicide-based programs on weed control. Sulfentrazone alone controlled common lamb’s-quarters and henbit but provided poor control of large crabgrass and yellow foxtail. However, a tank mix of norflurazon or oryzalin with sulfentrazone improved control of these weeds over sulfentrazone alone. Terbacil alone or in tank mix rimsulfuron, and flumioxazin alone gave excellent control of large crabgrass and yellow foxtail.     

Assessment of herbicides for use on the sweet herb,Stevia rebaudiana in the tropics

SUMMARY

The leaves and stems of Stevia rebaudiana produce steviol glycosides which are sweeter than sucrose, of low calorific value, pH- and heat-stable, and may have a variety of therapeutic benefits. Stevia seed germination is poor and the initial stages of growth are slow, which makes young plants susceptible to competition from weed species. In Australia, no herbicides are currently registered for use on Stevia. The purpose of this study was to assess the efficacy of 16 herbicides on S. rebaudiana and associated weeds. All 16 herbicides were trialled at their most relevant application rates at a field site in tropical Queensland. The best four performers were then tested at two rates of application at another tropical site. The post-planting, pre-weed emergence, oryzalin-containing herbicide, Prolan 500, at either 6.8 or 8.5 l ha^?1 provided the best weed control without affecting the biomass of the Stevia crop. High-performance liquid chromatography was used to determine if rebaudioside A and stevioside concentrations were affected in leaves treated with Prolan 500. It was found that at 1, 4, and 8 weeks after treatment, 8.5 l ha^?1 Prolan 500 resulted in significantly lower rebaudioside A and stevioside concentrations than applying Prolan 500 at 6.8 l ha-1. We therefore recommend that the oryzalin-containing herbicide, Prolan 500 is suitable for use on S. rebaudiana at an application rate of 6.8 l ha^?1.     

Selective post-emergence chemical control of Solanum nigrum L. and other broad leaved weeds in direct seeded processing tomatoes

Field experiments determined the effectiveness of post-emergence application of pen- tanochlor and acifluorfen in controlling Solanum nigrum L. in direct seeded processing tomatoes. Tomatoes tolerated both herbicides even at the one true-leaf stage with pen- tanochlor and at two true leaves with acifluorfen. Acifluorfen tolerance depended on rate, lower rates being least phytotoxic. Pentanochlor controlled S. nigrum from the cotyledon stage to five true leaves, allowing considerable flexibility in application timing. Rates of 10 to 15 1 ha-1 gave greater control than 5 1 ha-1. Acifluorfen rates as low as 0.5 1 ha"1 controlled S. nigrum up to the two true leaf stage. The two chemicals controlled different spectra of broad-leaf weeds.