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.     

Beyond patch spraying: site-specific weed management with several herbicides

Site-specific weed management can include both limiting herbicide application to areas of the field where weed pressure is above the economic threshold (patch spraying) and varying the choice of herbicide for most cost-effective weed control of local populations. The benefits of patch spraying with several, postemergence herbicides in irrigated corn were evaluated in simulation studies using weed counts from 16 fields. Patch spraying with one, two or the number of herbicides that maximized net return for a field was simulated. With patch spraying of one herbicide, the average area of a field left untreated is 34.5%. Net return increases by $3.09 ha⁻¹ compared to a uniform application without decreasing crop yield. Additional herbicides increase the average benefits with just 4% more of the field treated. With two herbicides, the increase in net return is almost tripled and herbicide use is reduced nearly 10-fold compared to patch spraying with one herbicide, and weed control is better than the uniform application in 10 fields. Using more than two herbicides for patch spraying further reduces weed escapes, but herbicide use is greater than a uniform application in 10 fields. Growers might be more willing to adopt patch spraying if more than one herbicide is used in a field.     

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.     

Variable-rate fungicide spraying in cereals using a plant cover sensor

Real-time technology was developed and tested to variably apply fungicides on the plant surface of cereals. An important step towards variable-rate fungicide application in real time is the development and operation of online sensors for measuring plant parameters. The sensor signal of the CROP-Meter (real-time sensor to measure crop biomass density) is correlated with the Leaf Area Index, a measurement characterising the plant surface. Geostatistical analysis of the sensor values in the experimental fields showed that the autocorrelation distance was greater than 25 m, which was wider than the spray boom of the sensor-controlled field sprayer. Control of individual sections of the spray boom was therefore not necessary in the 5-year experiments. In the eleven field trials, average fungicide savings of 22% were achieved. Field scale strip trials were conducted with the sensor-operated field sprayer to analyse the yield response of the crop. Higher, lower, as well as similar yield levels were obtained in the variable-rate plots by comparison with the uniform plots.     

Machine vision smart sprayer for spot-application of agrochemical in wild blueberry fields

An essential part of the wild blueberry cropping system is the proper management of agrochemical inputs including herbicides, fungicides and insecticides. A machine vision system was developed and mounted on the rear sprayer boom 0.18 m in front of the sprayer nozzles capable of targeting the agrochemical application on an as-needed basis. The three-point hitch mounted sprayer featured 27 nozzles over a 13.7 m boom width and a storage tank capacity of 1135 l. Nine digital color cameras continually take images in real-time while computer software processes the images in 0.15 s to determine the target locations where the nozzles open and spray at speeds up to 1.77 m s^?1. Two wild blueberry fields in central Nova Scotia were selected for smart sprayer performance testing with spot-application (SA) of agrochemical as compared to control and uniform application techniques. Chateau^® herbicide was applied in a field with an infestation of hair cap moss. Spray droplet comparison showed moss patches were properly targeted using the smart sprayer. SA provided the same coverage performance as compared to uniform on the moss targets with herbicide application savings of 78.5% using the smart sprayer. Harvestable yield results were similar for all application tracks. TruPhos Magnesium and ZincMax foliar fertilizers were tank mixed with Bravo^® and Proline^® fungicides and applied to compare the difference of SA, control and uniform application. Results showed SA of foliar fertilizer and fungicide led to less premature leaf drop and increased the blueberry stem height, number of branches, stem diameter and fruit buds. SA of foliar fertilizer and fungicide also increased the percent of healthy wild blueberry plants by 57.8% and the harvestable yield by 137.8%. Fungicide application savings using the smart sprayer for SA were 11.6%.     

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     

烟田中使用不同喷雾器的农药沉积分布研究

[目的]比较不同喷雾器以及喷头对农药有效利用率和施药效率的影响。[方法]采用诱惑红作为农药喷雾的示踪剂,分析了4种喷雾器及喷头在田间喷雾下的雾滴大小、施药效率、叶片农药的沉积回收率和雾滴田间分布均匀性。[结果]农药的有效利用率方面表现为电动喷雾器>机动喷雾器>手动喷雾器>手动弥雾器;施药效率方面表现为机动喷雾器>电动喷雾器>手动弥雾器>手动喷雾器;农药雾滴田间分布均匀性方面表现为电动喷雾器最好,其余都较差。[结论]为新型植保器械的推广应用提供了理论依据。     

果园风送式喷雾机设计

[目的]针对我国苹果生产过程中施药技术落后等的题,研究设计出一种新型果园喷雾机。[方法]通过对主要部件设计研制出了适应新型果园种植模式果园喷雾机,并进行试验验证。[结果]验证结果表明新型果园喷雾机工作效率高、噴量稳定、雾化均匀、穿透性好,能够满足新型种植模式果园施药要求。[结论]风送式果园喷雾机使用方便、节药节水,具有广阔应用前景。     

Variable-rate fungicide spraying in real time by combining a plant cover sensor and a decision support system

In recent years, real-time technology has been introduced into the practice of spraying variable fungicide rates in cereal fields. Plant parameters for characterising heterogeneous plant growth such as biomass or plant surface area can be indirectly detected by the sensor CROP-Meter. The sensor signal is correlated with the Leaf Area Index, which can be used to adapt the application rate. However, this relatively simple method of controlling variable-rate fungicide application does not take into account the differences in disease distribution. In practice, decision support systems such as proPlant expert.classic can provide information about disease infection probabilities, application time, fungicide products and application rates for uniform spraying. A prototype of the system proPlant expert.precise was developed to estimate infection risks from fungal diseases using weather and field-specific data for up to three management areas with different yield expectations. The system also considers economic factors such as expected yield and costs of the fungicide products in generating a spraying map with different fungicide dosages. The information from the CROP-Meter (sensor) and from the decision support system proPlant expert.precise (map) was combined to provide a real-time spraying system with map overlay. The system was tested in 2007 in three winter wheat fields. Compared with conventional uniform spraying the CROP-Meter with map overlay treatment resulted in up to 32.6% fungicide savings (CROP-Meter versus uniform: up to 20.3%). There was no yield reduction on average when the sensor-controlled spraying technologies were used.     

不同植保机械施药对水稻病虫防治效果的研究

对自走式喷杆喷雾机、多旋翼植保飞行器、背负式机动弥雾机3种不同植保机械施药的作业效果及水稻病虫防治效果进行比较。结果表明,自走式喷杆喷雾机与植保飞行器工效远高于背负式机动弥雾机,是背负式机动弥雾机的6.7~10.0倍。且自走式喷杆喷雾机用工成本较低,每公顷24元,植保飞行器用工成本每公顷36元,是背负式机动弥雾机的1/5~1/3。多旋翼植保机飞行器喷药速度比自走式喷杆喷雾机快,但电池充电耗时较长。自走式喷杆喷雾机喷幅宽,喷雾均匀、用水量足,与多旋翼植保飞行器均适用于大面积推广,值得应用。多旋翼植保飞行器对水稻病害的防治效果较差,其用水量与病害控制效果有一定的关系,建议加大用水量或添加沉降剂使用。     

不同药械在稻田喷洒分布量的研究

为提高湖南省作物病虫防治的药械整体水平,对国内外手动喷雾器和国产机动风送背负机两类药械的5种机型,9种喷射部件和4种喷洒方式,在水稻生长前、中、后期分别进行喷洒分布量试验研究。采用纸卡法及染色法测定法对不同药械洒液进行定性和定量测试,结果表明,两类药械喷洒后的沉积量、药液分布均匀性和农药利用率随水稻生育期增长而提高,机动风送喷洒优于手动药械喷哂。在机动药械试验中,在泰山3WF－2．6型非旋转喷头,水平沉积法喷洒效果最好,手动药械以西班牙产“没得比”喷洒效果最佳。     

喷雾技术对除草剂药效的影响

通过对喷雾器压力、喷嘴型号和药剂浓度的调节,对不同喷雾压力、不同喷嘴型号和不同药剂浓度下的除草效果进行调查分析,探讨影响喷雾质量的因素。结果表明：低压力范围内（30psi以下）,喷嘴型号越小,压力越高,雾化情况越好,防治效果好。     

无人机播前喷施除草剂防除棉田杂草效果评价

【目的】 分析不同喷药处理喷施33%二甲戊灵乳油对棉田杂草防效及棉花生长发育的影响,为棉田无人机播前喷施除草剂提供理论依据。【方法】 在新疆机采棉种植模式下,选择土壤封闭剂二甲戊灵为供试除草剂,设计播前无人机3个不同浓度喷药,车载喷药机喷药和不喷药5个处理,分析不同处理对棉田杂草防效及棉花生长发育的影响。【结果】 无人机喷施二甲戊灵进行棉田播前土壤处理,处理2(3 450 mL/hm²时)控草效果与车载喷药机处理相当,防治效果均达到94.00%,且显著好于不施药效果,出苗率均达59.71%,与不施药处理差异不显著。增加药剂浓度1 200 mL/hm²对棉花出苗有影响,出苗率降低7.54%,但差异不显著。无人机喷药处理株高、叶龄、地上部干物质重、叶面积指数与车载喷药机喷药处理间差异不显著,显著高于不喷药处理。【结论】 无人机喷施播前二甲戊灵浓度3 450 mL/hm²时与车载喷药机喷施浓度3 450 mL/hm²防草效果和棉花生长发育相当,可在大田推广使用。     

Camera steered mechanical weed control in sugar beet,maize and soybean

In sugar beet, maize and soybean, weeds are usually controlled by herbicides uniformly applied across the whole field. Due to restrictions in herbicide use and negative side effects, mechanical weeding plays a major role in integrated weed management (IWM). In 2015 and 2016, eight field experiments were conducted to test the efficacy of an OEM Claas 3-D stereo camera^® in combination with an Einböck Row-Guard^® hoe for controlling weeds. Ducks-foot blades in the inter-row were combined with four different mechanical intra-row weeding elements in sugar beet, maize and soybean and a band sprayer in sugar beet. Average weed densities in the untreated control plots were from 12 to 153 plants m^?2 with Chenopodium album, Polygonum convolvulus, Thlapsi arvense being the most abundant weed species. Camera steered hoeing resulted in 78% weed control efficacy compared to 65% using machine hoeing with manual guidance. Mechanical intra-row elements controlled up to 79% of the weeds in the crop rows. Those elements did not cause significant crop damage except for the treatment with a rotary harrow in maize in 2016. Weed control efficacy was highest in the herbicide treatments with almost 100% followed by herbicide band-applications combined with inter-row hoeing. Mechanical weed control treatments increased white sugar yield by 39%, maize biomass yield by 43% and soybean grain yield by 58% compared to the untreated control in both years. However, yield increase was again higher with chemical weed control. In conclusion, camera guided weed hoeing has improved efficacy and selectivity of mechanical weed control in sugar beet, maize and soybean.     

湿润直播稻田杂草的一次性化学防除技术的研究

扫特处理提供了优良的杂草鲜重防效和最高水稻产量 ,扫特是湿润直播稻田早期使用的最佳除草剂。丁苄对杂草的鲜重防效和水稻产量水平不亚于扫特 ,其配套技术是 :在水稻 1叶 1心期使用 ,用药时排干田水保持土壤湿润状态。二氯苄是直播稻田中期茎叶处理剂 ,最佳使用时间在水稻 2叶 1心期 ,排干田水后喷施。扁秆草的防效尚有待于提高