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随着化学药剂除草技术的推广应用,马铃薯田药剂除草已成为广大农民关心的问题,他们想用药又不知用什么药和怎样用药,为此笔者将此项技术介绍如下,敬请参考。1根据杂草种类选择药剂在明确田块上一年出现的杂草类别选择药剂,如果该田块上一年出现的杂草以禾本科杂草为主要杂草群落应选用拿扑净、盖草能等;如果该田块以禾本科杂草和小粒种子的阔叶杂草为主则应选用乙草胺、异丙甲草胺、乙草胺 嗪草酮、乙草胺 扑草净等;如田块内有鸭跖草、刺儿菜、苍耳、苣买菜等恶性杂草时可选用广灭灵或田得济、除草通。注意:马铃薯对氯嘧磺隆、普施特类药剂… 相似文献
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第一讲蔬菜田杂草 一、蔬菜田杂草的分类 (一)根据除草剂的防除对象分类这种分类方法通常把蔬菜田杂草分为三大类,即禾本科杂草、莎草科杂草和阔叶杂草。前二者又统称为单子叶杂草,后者又称双子叶杂草。蔬菜田杂草以阔叶杂草为最多,其次为禾本科杂草,莎草科杂草的发生数量最少。 单子叶杂草是指在种子胚内只含有一片子叶的杂草。双手叶杂草是指在种子胚内含有两片子叶的杂草。 禾本科杂草的主要特征是叶片狭长,茎圆形,有节,节间常中空,根须状。如种稗、牛筋草、千金子等。莎草科杂草与禾本科杂草的主要区别是茎大多为三棱形、实心,无节,个别为圆形,空心。如香附子、碎米莎草、水蜈蚣等。阔叶杂草的主要特征是叶片圆形、心形或菱形,叶脉通常为网状,茎圆形或方形。如小藜、凹头苋、马齿苋等。 相似文献
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据调查,上海、江苏、浙江的大蒜田杂草,数量多,危害大。草害严重的田块,每年亩损失产值达300元以上,据上海市嘉定县的试验,秋季杂草引起的损失大大超过春季杂草。我们于1986~1988年连续进行大蒜田秋季杂草的化学防除试验,总结如下。一、大蒜田秋季杂草种类及危害秋季杂草在大蒜田的危害,历时3个多 相似文献
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随着稻田栽培莲藕的浅水藕面积的增大,莲藕田的杂草危害也越来越严重。据我们调查:莲藕田杂草以禾本科的看麦娘、稗草、马塘、牛筋草等杂草为主,杂草密度每平方米少则800多株,多则1500多株, 相似文献
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安阳市麦田杂草发生危害逐年加重,杂草种类地区间大同小异,单块麦田内杂草种类多样化,阔叶草优势种显著改变,禾本科杂草发生量上升较快,局部恶性杂草危害严重,杂草密度年份间变化较大。本文分析了造成安阳市麦田杂草严重发生的原因:杂草的生物学原因、连续使用单一除草剂品种、杂草种类得到人为选择变化、杂草得不到有效控制、耕作管理不当等。 相似文献
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连续3年在2个不同耕作季节选择免耕、深耕不耙、深耕耙平、旋耕4种耕作方法,研究其对党参田间优势杂草种群的影响以及耕作方式协同杂草作用对党参产量的影响。结果表明:参田中一年生杂草以虫食(Corispermum declinatum Steph.ex Stev.var.declinatum)、荠(Capsella bursapastoris(Linn.) Medic)、灰灰菜(Chenopodium album L.)、狗尾草(Setaria viridis(L.) Beauv.)为优势种群,多年生杂草以田旋花(Convolvulus arvensis L.)、冰草(Agropyron cristatum(Linn.) Gaertn.)为优势种群;免耕参田杂草种类最多,数量最大,党参产量最低;夏季干旱时节深耕耙平参田杂草种类、数量均最少,党参产量最高。夏季高温干旱时节进行深耕耙平能够有效的控制党参田间杂草,提高参田产量,在一定程度上降低了除草成本,可作为党参绿色种植控草技术进行推广应用。 相似文献
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常见旱田难治杂草防治方法 总被引:1,自引:0,他引:1
杂草严重危害农作物正常生长,已被列为农业的一种自然灾害。根据中国农业部植物保护总站近年来的调查,我国的农田常见杂草有580余种,其中旱田杂草427种,占74%。由此可见,中国旱田杂草种类繁多,给杂草防除带来了许多困难。因此,搞好旱田杂草的综合治理,从根本上控制杂草的危害,提高作物产量,是迫不容缓的重要任务。 相似文献
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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. 相似文献
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Landscape simplification promotes weed seed predation by carabid beetles (Coleoptera: Carabidae) 总被引:1,自引:0,他引:1
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. 相似文献
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