Site-Specific Weed Control in Maize,Sugar Beet,Winter Wheat,and Winter Barley

A four-year study of site-specific weed control is presented in this paper. Weed seedling distribution was sampled and mapped prior to and after post-emergence herbicide application in four fields planted with maize, sugar beets, winter wheat and winter barley, rotating on one site. Herbicides and other weed control strategies were applied site-specifically according to the spatial variation of weed populations. Different decision algorithms were used for chemical weed control methods in each crop. A weed treatment map was created to direct location and dosage of herbicide application. The sprayer was coupled with a differential Global Positioning System (DGPS). The solenoid valves of the sprayer were opened automatically when the tractor entered a weed patch characterized in the weed treatment map. For site specific herbicide application, a patch sprayer was developed that allowed variable rate application and the selective control of each section of the spray boom.     

Two-Year Weed Seedling Population Responses to a Post-Emergent Method of Site-Specific Weed Management

Field experiments were conducted to determine how a site-specific weed management practice in Zea mays L. influenced the numerical and spatial distribution of a naturally occurring weed infestation in Z. mays and the succeeding Beta vulgaris L. crop. Compared to conventional broadcast herbicide applications, site-specific herbicide applications reduced herbicide load by 11.5 and 98.0% in two separate Z. mays fields. The broad range in outcomes was attributed to the spatial aggregation and density of target weed populations. While herbicide use was successfully reduced at field locations with low weed density, most survivors of multiple control tactics were in locations with the highest initial density. A greater understanding of interactions between weed management and weed density would increase the likelihood that site-specific weed management offers long-term improvements over conventional approaches.     

稻虾共作模式对稻田杂草的控制效果及其经济效益

为明确稻虾共作在稻田的应用效果及经济效益,研究了不同稻虾共作模式对稻田杂草的控制作用。结果表明,稻虾共作对田间主要杂草稗(Echinochloa crusgalli)、异型莎草(Cyperus difformis)、鸭舌草(Monochoria vaginalis)、陌上菜(Lindernia procumbens)及水苋菜(Ammannia baccifera)均具有良好的控制作用,防效可达85%以上,总体效果与化学除草处理36%苄嘧磺隆·二氯喹啉酸WP270 g(a.i)/hm~2相当。实施稻虾共作的稻田净收益为68 967.3~88 813.8元/hm~2,显著优于化学除草处理,较其收益增加4.7~6.3倍。     

Evaluation of Site-Specific Weed Management Implementing the Herbicide Application Decision Support System (HADSS)

A major concern of producers has always been how to reduce the amount of inputs required for crop production while maintaining or improving yields. One area of research addressing this issue is site-specific weed management (SSWM). The objective of this research was to evaluate the possibility of using SSWM herbicide applications to reduce overall production costs when site-specific weed populations are known. Weed populations of three soybean fields (B-East, B-South, B-North), located at the Black Belt Branch Experiment Station, Brooksville, MS, were estimated in 1998 and 1999. Sampling occurred July 8–9, 1998 (8 weeks after planting), and June 30–July 1, 1999 (6 WAP). An established 10 m × 10 m Universal Transmercator (UTM) grid coordinate system was used to divide the fields into 100 m² cells, with the sample point located in the center of each cell. Optimal herbicide recommendations were obtained for each sample location within each field by subjecting the weed information to the Herbicide Application Decision Support System (HADSS). An average of the weed populations for the entire field was also subjected to HADSS to obtain an optimal recommendation for a broadcast application for comparison purposes. Data from 1998 resulted in 25% and 15% of the field not requiring a herbicide treatment for the B-North and B-South when compared to the whole-field recommendations to receive broadcast treatments. However, B-East received a no treatment recommendation for the whole-field analysis. The no treatment recommendation was attributed to the sicklepod population exceeding a level deemed economically controllable by HADSS. However, when SSWM recommendations were generated, 49% of the field received no treatment recommendation, while 51% resulted in a herbicide application as an economical choice. In 1999, glyphosate-resistant transgenic soybean was used, thereby increasing the POST herbicide treatment options available in HADSS. Herbicide treatment recommendations resulted in 100%, 56%, and 91% of the total area requiring herbicide treatments for B-East, B-North, and B-South, respectively. Comparing the projected net returns for each field can develop a better estimate of the value of SSWM. In 1998, data from the B-East resulted in a projected net return increase of $21.63 ha^–1 over that of the broadcast application. Estimated net return increased $5.42 ha^–1 at B-North, with simulated SSWM applications over broadcast applications, and $14.67 ha^–1 increase at B-South. Net returns for 1999 resulted in only a $0.32 ha^–1 increase by using SSWM for B-East, but a $21.00 and $13.56 ha^–1 increase for B-North and B-South, respectively. The extra expenses of SSWM, such as sampling and technology costs, are not included in the net returns calculations and, when included, would reduce the difference between SSWM and conventional methods. This research has demonstrated the potential value of SSWM from an economic standpoint; environmental benefits through reductions in herbicide applications are also apparent.     

Crop/Weed Outcomes from Site-Specific and Uniform Soil-Applied Herbicide Applications

While uniform broadcast application (BC) of soil-applied herbicides is the norm, advances in geospatial technologies have enabled the deployment of site-specific herbicide application (SS). Since there are several, largely-untested decision rules for SS herbicide use, the objective of this work was to evaluate crop/weed outcomes and isoxaflutole use for a number of BC and SS strategies. Field experiments were established where isoxaflutole dose response functions were quantified from early-season Zea mays (L.), Sorghum bicolor (L.) Moench., and Abutilon theophrasti Medic. response data at multiple plots (64 in 1999; 62 in 2000) throughout a variable field. These data were then used to infer crop and weed outcomes from simulated application strategies. While BC and SS strategies that relied on the product label were similar in terms of total herbicide use, extent of crop tolerance, and A. theophrasti efficacy, the SS strategy resulted in a significant redistribution of herbicide. Using biologically effective doses (ED) resulted in the highest efficacy and herbicide use was highly species-dependent. By using a historical weed map of the field to guide herbicide application, herbicide use could be reduced some 20–48% when following the product label where seedlings were present, or >90% when using the ED for A. theophrasti. In order to maximize the potential agronomic benefits of SS, biological and spatial information of both the weed and soil should be taken into account.An erratum to this article can be found at     

热除草技术现状和展望

除草剂的广泛使用引发了环境污染、生物多样性减少、杂草群落变迁和杂草抗药性等诸多问题。热除草方法是替代化学除草的潜在方法,热除草方法有火焰除草、热水除草、蒸汽除草、红外辐射除草、激光除草等。热除草是快速加热植物体内的水分使植物细胞破裂失去活性、死亡的方法。各种热除草技术的传热机制不同。重点介绍了各种热除草技术的机理和在国内外的发展现状及所适用的环境和发展方向。随着有机农作的发展,热除草技术将发展成熟并得到广泛应用。     

麦田杂草防治技术

分析麦田杂草的危害及技术,并提出杂草防治关键技术。     

Soil and Weed Survey for Spatially Variable Herbicide Application on Railways

Weed control on railways is frequently done by herbicide application, using large amounts of chemicals and labour. Only a few hectares of surface area on a railway can be many kilometres long so high levels of spatial variability of soils and weeds are expected. Railway sprayers use similar technology to crop sprayers so it is possible to adopt concepts from precision agriculture for weed control. The objective of this study was to evaluate spatial variability of soils and weeds on railways in order to define weed control strategies and basic characteristics of a railway sprayer. This work is part of a research project aiming at the development of a system for spatially variable herbicide application on railways. Soil and weed data were collected from five different railway companies in Brazil. These data were used to simulate treatment maps based on weed control strategies and to estimate technical requirements for spatially variable herbicide application. The results showed that soil and weed survey gave important information for defining weed control strategies and spraying equipment. The sprayer must treat the three swaths (left, central and right parts of the railway surface) separately applying at least two different herbicides at the same time. On average, a variable dose rate application based on the treatment maps generated in this work could save up to 59% of herbicides.     

田间杂草识别与除草技术智能化研究进展

随着计算机与电子技术的发展,田间杂草识别与除草技术逐步走向智能化,自动除草系统成为国内外研究热点。本文对组成田间杂草识别与自动除草系统的4个主要模块(系统导航模块、图像采集与处理模块、杂草识别模块和除草控制模块)分别进行了综述和分析,并指出目前研究中存在的问题及今后努力的方向。     

Development of an Image Processing System and a Fuzzy Algorithm for Site-Specific Herbicide Applications

In precision farming, image analysis techniques can aid farmers in the site-specific application of herbicides, and thus lower the risk of soil and water pollution by reducing the amount of chemicals applied. Using weed maps built with image analysis techniques, farmers can learn about the weed distribution within the crop. In this study, a digital camera was used to take a series of grid-based images covering the soil between rows of corn in a field in southwestern Quebec in May of 1999. Weed coverage was determined from each image using a greenness method in which the red, green, and blue intensities of each pixel were compared. Weed coverage and weed patchiness were estimated based on the percent of greenness area in the images. This information was used to create a weed map. Using weed coverage and weed patchiness as inputs, a fuzzy logic model was developed for use in determining site-specific herbicide application rates. A herbicide application map was then created for further evaluation of herbicide application strategy. Simulations indicated that significant amounts of herbicide could be saved using this approach.     

控草和施肥对桉树生长影响的试验研究

为探索永安地区桉树速生丰产的营林抚育技术,通过采用随机组合,对2010年造林的巨桉桉树林设计了控草和施肥量不同的抚育组合：试验结果表明,对桉树林实行控草和施放肥料有利于促进林木生长,提高林分生物量和生产力;同时通过经济效益分析表明,在永安地区桉树林的最佳施肥量为底肥施放0.5kg桉树专用肥＋0.5kg钙镁磷（永安地区土壤缺磷元素）,当年追施一次0.25kg桉树专用肥,次年追施一次0.25kg桉树专用肥;控草方式以人工控草为主,有条件的林地实行化学除草,特别是五节芒等恶性杂草较多的山场优先考虑进行化学除草。     

生物防治杂草的研究进展

生物防治是杂草综合治理措施中长期控制杂草的最有效的办法。本文针对杂草生物防治的概念、应用情况、研究进展、存在问题进行了综述。     

Robotic Weed Control System for Tomatoes

A real-time intelligent robotic weed control system was developed for selective herbicide application to in-row weeds using machine vision and precision chemical application. The robotic vision system took 0.34s to process one image, representing a 11.43 cm by 10.16 cm region of seedline containing 10 plant objects, allowing the prototype robotic weed control system to travel at a continuous rate of 1.20 km/h. The overall performance of the robotic system in a commercial processing tomato field and in simulated trials is discussed.     

杂草生防真菌研究现状

杂草生防真菌是从罹病杂草组织中分离筛选获得的一类能够有效侵染有害植物,并在一定程度上控制其生长或繁殖的植物病原真菌。利用杂草病原真菌防控杂草具有巨大的潜在优势。本文从杂草生防真菌的控草潜力、主要类群、生物防控机理、寄主范围、应用前景等方面总结了杂草生防真菌的研究现状,以期为杂草生防真菌的开发与利用提供一定的参考。     

Sugarbeet Yield Monitoring for Site-Specific Farming Part II–Field Testing

A field study was conducted to evaluate three real-time weighing systems to measure sugarbeet yield. Two systems permit use of the storage hopper onboard the harvester. The effects of tare on yield measurement were investigated. Parallel yield data from the three systems were compared. There was a strong relationship between systems as sugarbeet flow rates changed. High standard deviations were found for all product flow sensors. There was no statistical difference between two of the sensors, but there was for the other. One system provided unacceptable results. One of the systems provided reasonable accuracy and permitted use of the onboard storage hopper.     

抛栽水稻田间杂草生态防治阈期

通过多年多点试验 ,建立抛栽水稻大田立苗后有草天数或无草天数与水稻产量损失率之间的函数关系 ,以探明抛栽水稻田间杂草的生态防治阈期。结果表明 :抛栽水稻田间杂草的生态防治阈期 ,汕优 6 3为抛后 14～ 2 3d ;武运粳 8号为抛后 12～ 31d ,此时水稻处于 6叶期至 8叶期 ,此阈期的始期和终期为田间杂草密度及生物量的快速增长期。在此阈期内保持田间无草 ,既能使杂草造成的水稻减产率低于 3% ,又能充分发挥杂草在田间生态系统中所起的积极作用     

40%乙·扑乳油防除玉米田杂草试验

通过田间小区及大区对比试验的结果表明,40%乙草胺(Acetochlor) 扑草净(Prometryne)EC,对玉米田多种杂草,如稗草、马唐、狗尾草、鸭跖草、藜、铁苋菜等均有特效,防除效果稳定在90%以上。在杂草基数低于200株·m-2的地块,用药量为3000mL·hm-2,超过200株·m-2的地块,用药量为3750~4500mL·hm-2,施药时期为播种后5~9d。该除草剂对玉米安全、无药害,且不影响下茬作物生长。     

稻茬免耕移栽油菜田杂草的防除技术研究

为了有效控制稻茬免耕移栽油菜田杂草的发生和危害,采用小区试验与大区试验示范相结合的方法,研究了50%乙草胺乳油100mL+200g/L百草枯水剂150mL/667m2、50%乙草胺乳油100mL+41%草甘膦异丙胺盐水剂150mL/667m2、200g/L百草枯水剂150mL/667m2、41%草甘膦异丙胺盐水剂150mL/667m2等不同药剂的杂草防除效果。结果表明:小区试验,药后60d,以上不同药剂处理对棒头草、碎米荠菜、毛茛、稻搓草等杂草鲜重防效均在90%以上;大区试验示范,在免耕油菜移栽3d前,用20%百草枯水剂150mL/667m2+50%乙草胺乳油100mL/667m2对免耕移栽油菜田杂草进行处理,以及在油菜生长阶段,根据田间杂草的草相组成,选择喷施50%草除灵悬浮剂或10.8%高效氟吡甲禾灵乳油防除,防效均在80%以上。采用以上技术措施能有效控制免耕油菜田杂草对油菜的危害,油菜生长安全。     

Weed Detection Using Canopy Reflection

For site-specific application of herbicides, automatic detection and evaluation of weeds is desirable. Since reflectance of crop, weeds and soil differs in the visual and near infrared wavelengths, there is potential for using reflection measurements at different wavelengths to distinguish between them. Reflectance spectra of crop and weed canopies were used to evaluate the possibilities of weed detection with reflection measurements in laboratory circumstances. Sugarbeet and maize and 7 weed species were included in the measurements. Classification into crop and weeds was possible in laboratory tests, using a limited number of wavelength band ratios. Crop and weed spectra could be separated with more than 97% correct classification. Field measurements of crop and weed reflection were conducted for testing spectral weed detection. Canopy reflection was measured with a line spectrograph in the wavelength range from 480 to 820 nm (visual to near infrared) with ambient light. The discriminant model uses a limited number of narrow wavelength bands. Over 90% of crop and weed spectra can be identified correctly, when the discriminant model is specific to the prevailing light conditions.     

施用草甘膦对转基因抗除草剂大豆田杂草防除、大豆安全性及杂草发生的影响

【目的】转GAT和EPSPS双价基因抗草甘膦大豆‘GE-J16’是我国具有自主知识产权的抗除草剂材料,喷施草甘膦后,评价草甘膦对杂草防除、大豆安全和杂草发生的影响,为其将来商业化种植后的安全监测与杂草治理提供数据支持。【方法】除草效果:每小区以对角线5点取样法取5个0.25 m2样点并标记,施药后28 d调查禾本科和阔叶杂草株数,并剪取地上部分称取鲜重,计算株防效和鲜重防效。对大豆安全性:每小区以对角线5点取样法,每点随机取4株大豆并标记,在喷药当天、药后7、14、21及28 d调查大豆株高和复叶数,观察药害,收获前每小区取50株大豆调查结荚数及产量。杂草发生情况:每小区以对角线5点取样法取5个0.25 m2样点并标记(避开除草效果取样点),调查并记录每种杂草种类、株数,计算每种杂草相对多度。【结果】转基因大豆喷施900、1 800和3 600 g a.i./hm2草甘膦对禾本科杂草株防效2016年分别为84.30%、95.22%和83.62%,阔叶杂草株防效分别为49.80%、64.52%和61.93%,禾本科和阔叶杂草鲜重防效分别在95.36%和82.05%以上,2017年对禾本科...