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果园采用化学除草省时、省力,经济上比较合算。若是施用技术掌握不好,也会给生产带来损失。为此,在施用除草剂时,应注意以下几点。１．除草剂种类：许多除草剂都有选择性,选用不当,会直接影响灭草效果,各地应针对果园主要杂草种类而选用。如克芜踪防除１、２年生杂草效果较好,但对多年生杂草只能杀死地上部分;而茅草枯虽是防除深根性杂草的优良除草剂,但对某些１、２年生杂草,防效却较差。从近年各地施用情况看,草甘膦是较为理想的果园除草剂,对果园常见的１００多种恶性杂草,都有良好的防除效果,施用得当,果树不易受药害。… 相似文献
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１９９３－１９９４年调查，武汉地区桔园共有杂草７２种，分属２６个科；全年有２次杂草发生高峰；主要的果园杂草有野燕麦、看麦娘、马唐、绿狗尾、牛筋草、空心莲子草、旱苗蓼等。另调查了不同生草草种对果园杂草发生的影响，结果以栽种进喜草对杂草发生具有较强的抑制效果。 相似文献
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以前果园除草,主要使用10%的草甘膦水剂,但由于长期使用,效果差.为筛选果园除草剂品种,选用了华北制药厂生产的爱诺园草净在桑园中进行除草试验,对该除草剂在生产中的安全使用、经济有效使用剂量及除草范围进行了研究,为果园除草选用除草剂提供参考. 相似文献
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双草克防除旱地杂草试验襄北农场植保站（４４１１２３）李复宁双草克是一种新型旱地除草刘，为了探明其除草效果和使用方法，以便大田推广，１９９６年进行了小区试验。１材料与方法１．１供试药剂３５％双草克乳油（合肥丰乐农化厂产品）；１０．８％高效盖草能乳油（美... 相似文献
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酰胺类杀草膜是含有酰胺类除草剂的新型复合地膜,具有显著的除草作用,又具有一定的增产效果。目前甲草胺及都尔杀草膜已开始在棉花、花生、蔬菜等多种作物上应用,防除单子叶杂草效果在90％以上,较普通地膜增产10％以上。而乙草胺杀草膜则是正在开发研制的杀草膜中的一个新品种。为了进一步选择适用于生产的杀草膜品种,于1988～1990年对3种酰胺类杀草膜防除棉田杂草进行了试验和示范。 相似文献
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The effects of three different weed management strategies on the required input of hand weeding in an arable organic farming system, the weed seedbank in the soil and the emerging weed seedling emergence were studied from 1996 to 2003. Strategies were based on population dynamic models and aimed for (1) control of weeds as carried out in standard organic farming practice, (2) control of all residual weeds that grow above the crop and (3) prevention of all weed seed return to the soil. Under all strategies, the size of the seedbank increased during the conversion from conventional to organic farming systems. The increase under strategy 3 was significantly smaller than the increase under the other strategies. From 1999 onwards, the weed densities in plots treated with strategy 3 became significantly lower than the weed densities in plots treated with the other strategies. The time needed for hand‐weeding required to prevent weed seed return, in addition to the time needed in standard organic farming practices, reduced during the course of the study. A management strategy aimed at the prevention of seed return (strategy 3) can reduce the size of the increase of the seedbank, which is usually observed after transition from conventional to organic farming. This study provides unique real‐world data that are essential for evaluating population dynamic models. The results may contribute to the development of weed management systems based on ‘no seed’ threshold strategies and to a further decrease in the dependence on herbicides. 相似文献
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Weeds have negative impacts on crop production but also play a role in sustaining biodiversity in agricultural landscapes. This trade‐off raises the question of whether it is possible to promote weed communities with low competitive potential but high value to biodiversity. Here, we explored how weed communities respond to different vineyard management practices in South Africa's Western Cape, aiming to identify whether any specific practices are associated with more beneficial weed communities. Eight weed community characteristics representative of abundance, diversity and functional composition were used as indicators of competitive potential and biodiversity value. We explored how these responded to farm management strategy (organic, low input or conventional) and weed management practices (herbicides, tillage, mowing or combinations of these) using ordination and mixed models. Mown sites were associated with weed communities of high biodiversity value, with higher weed cover in both winter and summer, higher diversity and more native weeds. Mowing also promoted shorter weeds than either tillage or herbicides, considered to be less competitive with grapevines. However, high summer weed cover may be problematic where competition for water is critical, in which case tillage offers a method to limit summer weed cover that did not adversely affect diversity or native weeds. In contrast, herbicide‐treated sites had characteristics indicative of a lower biodiversity value and higher potential for competitiveness with few native weeds, lower diversity and relatively tall, small‐seeded weeds. Mowing in winter combined with tillage in spring may thus optimise the biodiversity benefits and production costs of Western Cape vineyard weeds. 相似文献
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Charles N. Merfield 《Weed Research》2023,63(2):83-87
Ecological weed management (EWM) considers that not all non-crop plants cause harm, and that non-harmful species ‘aliae plantae’ should be retained to provide multiple positive benefits. Only plants causing ‘significant harm’ are defined as weeds and should be controlled. However, this is difficult to achieve with current herbicide and mechanical weeding technologies. Robotic weeders may be able to facilitate EWM. Four Levels of robotic weeders are defined: Level 1 are row followers; Level 2 identify individual crop plants and weed around them; Level 3 individually identify all plants and individually kill all non-crop plants; Level 4 weeders individually distinguish crop plants, aliae plantae, and weeds and only kill the weeds, thus facilitating EWM. Currently only Levels 1–3 robotic weeders exist. The aim of proposing Level 4 robotic weeders is to highlight, particularly to roboticists, that the end goal of robotic weeding should not be crop monocultures, but biodiverse fields through EWM. It is envisaged that Level 4 robotic weeders would not just operate in vegetable crops, which are the current focus of Level 3 weeders, but in all crops, such as fruit trees, where they could, for example, control weeds in living mulches. It is therefore considered essential that weed scientists and roboticists collaborate to ensure that robotic weeders achieve EWM, not monocultures. If this vision can be realised, it could usher in a revolution in weed management. 相似文献
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Weed suppression by cover crops: comparative on‐farm experiments under integrated and organic conservation tillage 
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下载免费PDF全文 Cover crops are increasingly being used for weed suppression and to enhance the sustainability of agro‐ecosystems. However, the suitability of cover crops for weed suppression in integrated and organic conservation tillage systems is still poorly investigated. Therefore, a 2‐year field study at eight sites was conducted to test the weed suppressive potential of six legume‐based cover crops, with the aim to reduce herbicide input or mechanical weed management interventions. In all experiments, cover crops were directly sown after cereals before next year's main crop (grain maize or sunflower). The presence of cover crops caused a 96% to 100% reduction of weed dry matter at the four sites managed under integrated production, while effects were lower at the four sited managed under organic production, ranging from 19% to 87%. Cover crops that covered soil quickly and which produced much dry matter had the best weed suppressive potential. However, their weed suppressing effect was difficult to predict, as it depended on the year of the investigation, experimental site, cover crop species, the speed of soil cover in autumn and the density of the resulting mulch layer in spring. The study demonstrated that cover crops are a useful tool to suppress weeds under integrated and organic conservation tillage practices. Our recommendation for supporting weed management in conservation tillage systems is to use locally adapted cover crops that have rapid establishment, good soil coverage and high dry matter production. However, additional weed management measures are required for reliable weed control under on‐farm conditions. 相似文献
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The implications of spatially variable pre‐emergence herbicide efficacy for weed management 下载免费PDF全文
下载免费PDF全文 Helen Metcalfe Alice E Milne Richard Hull Alistair J Murdoch Jonathan Storkey 《Pest management science》2018,74(3):755-765
BACKGROUND
The efficacy of pre‐emergence herbicides within fields is spatially variable as a consequence of soil heterogeneity. We quantified the effect of soil organic matter on the efficacy of two pre‐emergence herbicides, flufenacet and pendimethalin, against Alopecurus myosuroides and investigated the implications of variation in organic matter for weed management using a crop–weed competition model.RESULTS
Soil organic matter played a critical role in determining the level of control achieved. The high organic matter soil had more surviving weeds with higher biomass than the low organic matter soil. In the absence of competition, surviving plants recovered to produce the same amount of seed as if no herbicide had been applied. The competition model predicted that weeds surviving pre‐emergence herbicides could compensate for sublethal effects even when competing with the crop. The ED50 (median effective dose) was higher for weed seed production than seedling mortality or biomass. This difference was greatest on high organic matter soil.CONCLUSION
These results show that the application rate of herbicides should be adjusted to account for within‐field variation in soil organic matter. The results from the modelling emphasised the importance of crop competition in limiting the capacity of weeds surviving pre‐emergence herbicides to compensate and replenish the seedbank. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献16.
P Bàrberi 《Weed Research》2002,42(3):177-193
Summary Despite the serious threat which weeds offer to organic crop production, relatively little attention has so far been paid to research on weed management in organic agriculture, an issue that is often approached from a reductionist perspective. This paper aims to outline why and how this problem should instead be tackled from a system perspective. Compared with conventional agriculture, in organic agriculture the effects of cultural practices (e.g. fertilization and direct weed control) on crop:weed interactions usually manifest themselves more slowly. It follows that weed management should be tackled in an extended time domain and needs deep integration with the other cultural practices, aiming to optimize the whole cropping system rather than weed control per se . In this respect, cover crop management is an important issue because of its implications for soil, nutrient, pest and weed management. It is stressed that direct (physical) weed control can only be successful where preventive and cultural weed management is applied to reduce weed emergence (e.g. through appropriate choice of crop sequence, tillage, smother/cover crops) and improve crop competitive ability (e.g. through appropriate choice of crop genotype, sowing/planting pattern and fertilization strategy). Two examples of system-oriented weed management systems designed for organic agriculture are illustrated as well as future perspectives and problems. 相似文献
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Floristic composition and species diversity of weed community after 10 years of different cropping systems and soil tillage in a Mediterranean environment 下载免费PDF全文
下载免费PDF全文 Sustainable cropping systems based on low inputs have received much attention, even if they may lead to the establishment of a competitive weed flora. This study, conducted from 2011 to 2014 in a Mediterranean environment, evaluated the changes in weed community composition in two cropping systems [conventional (CONV ) and organic (ORG )] with different soil tillage [inversion tillage (IT ) and non‐inversion tillage (NoIT )] in a wheat–tomato–chickpea rotation that began in 2000. The treatments were replicated three times according to a randomised complete block design. The organic system was managed according to EU regulations. Inversion tillage consisted of mouldboard ploughing to a depth of 30 cm, while NoIT consisted of subsoiling to a depth of 20 cm. Weed control was based on herbicide application in CONV and mechanical weeding in ORG . The organic non‐inversion system showed the highest weed biomass (134, 128 and 195 g dry matter (DM ) m?2 in wheat, tomato and chickpea, respectively) and weed density (66, 77 and 76 plants m?2 in wheat, tomato and chickpea, respectively), as well as community richness. However, ORG always increased weed diversity, even if annual dicotyledon species were abundant in ORG ‐IT and perennial dicotyledon species in ORG ‐NoIT . The conventional system enhanced the relative frequency of both annual (CONV ‐IT ) and perennial (CONV ‐NoIT ) grasses. There was a negative correlation between density of perennial weeds and crop yield (r 2 = 0.24, P < 0.001). Therefore, in the Mediterranean environment, combining organic practices with non‐inversion tillage could lead to the establishment of perennial weeds that are difficult to control, thus requiring specific weed management practices. 相似文献
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Greater adoption and refinement of low-external-input (LEI) farming systems have been proposed as ways to ameliorate economic, environmental and health problems associated with conventional farming systems. Organic soil amendments and crop diversification are basic components of LEI systems. Weed scientists can improve the use of these practices for weed management by improving knowledge of four relevant ecological mechanisms. First, multispecies crop rotations, intercrops and cover crops may reduce opportunities for weed growth and regeneration through resource competition and niche disruption. Secondly, weed species appear to be more susceptible to phytotoxic effects of crop residues and other organic soil amendments than crop species, possibly because of differences in seed mass. Thirdly, delayed patterns of N availability in LEI systems may favour large-seeded crops over small-seeded weeds. Finally, additions of organic materials can change the incidence and severity of soil-borne diseases affecting weeds and crops. Our research on LEI sweetcorn and potato production systems in central and northern Maine (USA) suggests that these mechanisms can reduce weed density and growth while maintaining crop yields. Low-external-input farming systems will advance most quickly through the application of interdisciplinary research focused on these and other ecological mechanisms. 相似文献
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移栽甜玉米田覆盖控草技术 总被引：1，自引：0，他引：1
为了明确不同覆盖方式对甜玉米田杂草出苗生长的抑制效果,寻求更安全环保的控制甜玉米田杂草发生危害的方法,本研究采用大田试验,在甜玉米移栽前,将不同厚度的玉米秆、水稻秆及1层黑色地膜均匀覆盖于小区内.结果显示,处理后20、40 d,黑色地膜能完全抑制甜玉米田杂草的生长,且能显著提高甜玉米产量,增产率为45％;不同厚度的稻秆和甜玉米秆覆盖能够控制杂草的发生,且覆盖厚度越厚,控草效果越好,顺序为稻秆20 cm＞甜玉米秆20 cm＞稻秆10 cm＞甜玉米秆10 cm.秸秆覆盖均能显著增加甜玉米的产量,且甜玉米秆20 cm处理的甜玉米产量最高,但彼此间无显著性差异. 相似文献
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不同施肥方式对稻麦轮作制稻田杂草群落的影响 总被引：1，自引：0，他引：1
为揭示不同施肥(纯施化肥、有机肥配施化肥、秸秆还田配施有机无机肥、有机无机复混肥)对稻—麦两熟制区稻田杂草的影响,以南京农业大学连续4年固定施肥金坛试验田为材料,于2014年水稻收获前进行了杂草群落调查,研究不同施肥、秸秆还田水稻田间杂草种类、密度、高度和杂草多样性指数的差异。结果表明:试验水稻田共记录杂草16种,分属7科、11属。稗草(Echinochloa crusgalli)、鸭舌草(Monochoria vaginalis)、多花水苋(Ammannia multiflora)、水苋菜(A.baccifera)、陌上菜(Lindernia procumbens)广泛分布于各试验田块。长期施肥可减少稻田杂草种类及发生密度。其中阔叶杂草和莎草科杂草在试验设定的各施肥措施下其种类和密度均显著下降,但株高显著增加;禾本科杂草种类、密度和株高几乎不受影响。秸秆还田配施化肥、有机肥配施化肥、有机无机复混肥+穗肥尿素和纯施化肥的田块中,杂草群落多样性指数低、均匀度指数相对较低,优势度指数较高,容易使单一优势杂草种类暴发,造成较严重危害;秸秆还田配施有机肥化肥、有机无机复混肥一次施用的稻田环境中,杂草群落多样性指数较高,均匀度指数较高,优势度指数较低,杂草群落结构较复杂,群落相对较稳定,且杂草密度较低,对水稻的生长危害较轻。 相似文献