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1.
BACKGROUND
Multicopters are used for releasing particulates seeds, fertilizer and spray. Their low cost and high manoeuvrability make them attractive for spraying in steep terrain and areas where overspray is undesirable. This article describes a model of multicopter wake and its influence on particulate dispersion, which is computationally economical compared to many computational fluid dynamics (CFD) approaches, yet retains reasonable accuracy.RESULTS
A model was successfully implemented in OpenFOAM . It features source terms for the rotor wash, Lagrangian particle tracking, an evaporation model, and a porous medium approach to model the effect of the ground vegetation. Predictions were validated against the field tests of Richardson et al. which used a DJI Agras MG-1 multicopter in three different flights with airspeeds of 3.2–4.9 m s−1, ground speeds of 2.1–2.9 m s−1 and cross-wind speeds of 0.04–2.2 m s−1. The effective swath width (30% line separation) was predicted to within one standard deviation. Sensitivity to a rotor rotational speed, flight height, flight velocity, multicopter roll and yaw angles, surface roughness length, plant height and leaf density was checked.CONCLUSION
In all flight trials, the modelled swath was closest to the experimentally obtained swath when the surface roughness of the fetch was equal to 0.5 m (bushes) and the rotational speed of all rotors was equal to 2475 rpm with 0.75R (0.2 m) tall plant canopy (grass) introduced to the model. The model showed acceptable validity for flight velocities of ≤2.8–5 m s−1 when flight parameters can be approximately estimated. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献2.
以人工饲料中添加低浓度的Cry1Ac杀虫蛋白(0、5、10、20μg/g)饲养甜菜夜蛾5个世代,探讨低浓度杀虫蛋白连续刺激对该虫处女蛾与产卵蛾飞行速度、飞行时间与飞行距离的影响。结果表明,甜菜夜蛾对低浓度Bt毒素的响应经过了敏感期、逐步适应期到最终适应甚至反弹几个阶段:在F1代,对照组的飞行距离显著长于最高浓度处理组。F2、F3代,低浓度处理(5~10μg/g)后的甜菜夜蛾飞行力开始增强,高浓度杀虫蛋白处理组(20μg/g)的飞行力仍低于对照,不同处理在飞行时间与飞行距离上差异显著。在F4代,处女蛾的飞行力开始回升,特别是低浓度处理(5μg/g)的飞行时间和飞行距离显著高于对照,也显著或极显著高于其他2个浓度处理,各处理在飞行时间和飞行距离上达到显著差异。到了F5代,所有处理的飞行力均大于对照,其飞行速度、飞行时间与飞行距离3个指标在各处理间均达到显著差异。研究同时发现,无论是处女蛾,还是产卵雌蛾,对低浓度Cry1Ac杀虫蛋白的响应基本一致。文章认为,阐述毒蛋白对昆虫飞行的影响需要研究多个世代。 相似文献
3.
草地贪夜蛾的飞行能力测定 总被引：3，自引：0，他引：3
迁飞是草地贪夜蛾Spodoptera frugiperda(J. E. Smith)快速扩散的生物学基础。本研究对草地贪夜蛾1～13日龄成虫飞行参数的测定表明:1～5日龄的个体具有较强的飞行能力,3日龄达到峰值后逐渐下降。3日龄个体吊飞24 h,平均飞行距离、飞行时间和飞行速度分别为(29.21±1.54)km、(11.00±0.47)h和(2.69±0.10)km/h。1～11日龄成虫的振翅频率无显著差异,平均振翅频率范围为42.39～44.64 n/s。相同日龄雌、雄蛾的飞行距离和飞行时间均无显著差异,但1日龄雄蛾的平均飞行速度显著大于雌蛾。补充营养组成虫的飞行距离和飞行时间显著高于未补充营养组。研究结果为深入阐明草地贪夜蛾的飞行生物学和迁飞机制提供了科学基础。 相似文献
4.
以广东极飞无人飞机P20为喷雾器械，以240 g/L噻呋酰胺悬浮剂和5%阿维菌素乳油为防治药剂，开展了无人飞机低容量喷雾中作业参数 (飞行高度和飞行速度)、喷雾用水量及喷头类型4个因素对水稻纹枯病、二化螟防治效果的影响评价。结果表明:在飞行速度的4个处理 (3、4、5、6 m/s) 中，药剂对水稻纹枯病、二化螟的防治效果均表现为飞行速度越慢，防效越高；在飞行高度的4个处理 (1.5、2.0、2.5、3.0 m) 中，药剂对水稻纹枯病、二化螟的防治效果均表现为作业高度为2.0和2.5 m的防效较高，且均显著高于作业高度为1.5和3.0 m的防效；在用水量的3个处理 (7.5、15.0、22.5 L/hm2) 中，药剂对水稻纹枯病、二化螟的防治效果均表现为用水量越多，防效越高，且三者之间的差异均达显著性水平；在两种类型的喷头中，离心式喷头 (极飞P20) 与压力式喷头 (大疆T16) 对水稻纹枯病、二化螟防效的影响均无显著性差异。根据以上结果优化的作业参数为:飞行速度3~4 m/s，飞行高度2~2.5 m，喷雾用水量为15.0~22.5 L/hm2。 相似文献
5.
The redistribution of insects that are released from an airplane is described using a diffusion equation to derive optimal spacing of flight lines and time interval between flights to achieve a reasonably uniform spatial distribution of released insects and to minimize costs. This optimization is done based on relative costs of sterile males and of flying time. An example is presented using data on the Mediterranean fruit fly, Ceratitis capitata (Weidmann), from the Moscamed program in Guatemala. For the parameter values used, the cost (sterile males plus flights) is minimized when insects are released at intervals of approximately every 2 days (for daily mortality μ = 0.24) to 10 days (for μ = 0.04) and flights are spaced at 300 m (for μ = 0.24) to 600 m (for μ = 0.04) apart, depending on daily medfly mortality estimates, which vary widely in the literature. A simpler approximate method of optimization is then presented based on a relationship observed in the optimization results between flight-line separations and the standard deviation of the distribution. 相似文献
6.
Kevin Malod Eleftheria-Maria D. Bali Corentin Gledel Laura Moquet Anandi Bierman Evmorfia Bataka Christopher W. Weldon Minette Karsten Hélène Delatte Nikos T. Papadopoulos John S. Terblanche 《Pest management science》2023,79(11):4153-4161
Background
Thermal history may induce phenotypic plasticity in traits that affect performance and fitness. One type of plastic response triggered by thermal history is acclimation. Because flight is linked to movement in the landscape, trapping and detection rates, and underpins the success of pest management tactics, it is particularly important to understand how thermal history may affect pest insect flight performance. We investigated the tethered-flight performance of Ceratitis capitata, Bactrocera dorsalis and Bactrocera zonata (Diptera: Tephritidae), acclimated for 48 h at 20, 25 or 30 °C and tested at 25 °C. We recorded the total distance, average speed, number of flight events and time spent flying during 2-h tests. We also characterized morphometric traits (body mass, wing shape and wing loading) that can affect flight performance.Results
The main factor affecting most flight traits was body mass. The heaviest species, B. dorsalis, flew further, was faster and stopped less often in comparison with the two other species. Bactrocera species exhibited faster and longer flight when compared with C. capitata, which may be associated with the shape of their wings. Moreover, thermal acclimation had sex- and species-specific effects on flight performance. Flies acclimated at 20 °C stopped more often, spent less time flying and, ultimately, covered shorter distances.Conclusion
Flight performance of B. dorsalis is greater than that of B. zonata and C. capitata. The effects of thermal acclimation are species-specific. Warmer acclimation temperatures may allow pest fruit flies to disperse further and faster. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献7.
两种植保无人机对火龙果冠层的作业参数优化 总被引：1，自引：0，他引：1
为探究飞行作业参数对植保无人机喷雾雾滴在火龙果冠层沉积分布规律的影响,明确植保无人机作业时雾滴的最佳分布效果,通过采用飞行高度、飞行速度、航线方向3个因素的3个水平正交试验,综合分析T16多旋翼和F5A电动单旋翼2种植保无人机在不同作业参数下在火龙果冠层的雾滴密度和覆盖率。结果表明：在相同喷施量情况下,影响这2种植保无人机雾滴分布的主次因素不一致,影响T16多旋翼植保无人机雾滴分布的主次因素依次为作业高度、作业速度、航线方向;影响F5A电动单旋翼植保无人机雾滴分布的主次因素依次为作业速度、作业高度、航线方向。优化了2种植保无人机在火龙冠层的作业参数,T16多旋翼植保无人机最佳作业参数是平行或垂直于种植行飞行,飞行高度为1.0 m,飞行速度为3.0 m/s;F5A电动单旋翼植保无人机最佳作业参数是垂直或平行于种植行飞行,飞行高度为2.0 m,飞行速度为2.0 m/s。这2种植保无人机飞行速度越小,飞行高度越低,其雾滴在火龙果冠层分布越好,雾滴穿透性也越好。在最优参数下,2种植保无人机喷雾雾滴在火龙果各个冠层都能达到比较好的分布效果,冠层下层雾滴密度高于冠层其他层。 相似文献
8.
Cereal aphid flight was monitored by 12.2 m suction traps at Szolnok in the middle of the Great Hungarian Plain and at Rothamsted, UK. Flight activities of Rhopalosiphum padi, Metopolophium dirbodum and Sitobion avenae were compared by the cross correlation function (CCF) between Hungary and UK. There was significant synchrony between flight a-tivity in Hungary and UK of R padi, M. dirbodum and S. avenae based on the eight years weekly sample data. The peak flight occurred 1, 3 and 2 weeks later at Rothamsted than at Szolnok for the three species (the CCF values were at – 1 week lag, r = 0.854, – 3 week lag r = 0.809, – 2 week lag r = 0.883, P < 0.05 respectively). When the flights in individual years were compared within species and between places the syn-chrony was lowest for R. padi: – in 4 years out of 8 and there was no synchrony, in the other years when synchrony occurred the time lag varied between – 1 week and – 4 weeks. For M. dirhodum the time lag varied between 1 and – 5 weeks, the synchrony was the best for S. avenae the week lag varied between 0 and – 3 weeks.Our results show that flight activity of cereal aphids at Szolnok occurs 1-3 weeks earlier than at Rothamsted. The crop season is earlier in Hungary than in England. 相似文献
9.
Abstract V.I.v. captafol spray treatments applied using a 1.8m swath (3.3 kg a.i./ha/application) were more effective than treatments using a 3.6 m swath (1.67 kg a.i./ha/application). At sites with more than 700 mm rainfall during the crop's field life weekly applications were more effective than spraying at 10- and 14-day intervals, but at the drier sites (< 650 mm rainfall) spraying at 10 days was adequate. 相似文献
10.
美洲斑潜蝇自然种群生命表及飞行能力的研究 总被引：3，自引：0，他引：3
美洲斑潜蝇ＬｉｒｉｏｍｙｚａｓａｔｉｖａｅＢｒａｎｃｈ．田间自然种群中,幼虫期的死亡率最高,１、２、３龄幼虫平均死亡率分别为４８．１４％、５０．８６％、７８．９７％,幼虫期被寄生蜂寄生的概率随龄期的增大而增高,从１龄的１．４４％上升到３龄的６０．８８％。应用微型昆虫飞行磨（Ｆｌｉｓｈｔｍｉｌｌ）计算机联机装置对不同日龄成虫的飞行能力进行了测试,结果表明：雌虫飞行能力随日龄的增大而增强,３日龄最大连续飞行的时间为８．８３分钟,距离为２７２．９３ｍ。雄虫以２日龄成虫飞行能力最强,最长的一次连续飞行时间可达２５．００分钟,距离为８８２．８８ｍ。 相似文献
11.
Krishna N Reddy Wei Ding Robert M Zablotowicz Steven J Thomson Yanbo Huang L Jason Krutz 《Pest management science》2010,66(10):1148-1154
BACKGROUND: Glyphosate drift from aerial application onto susceptible crops is inevitable, yet the biological responses to glyphosate drift in crops are not well characterized. The objectives of this research were to determine the effects of glyphosate drift from a single aerial application (18.3 m swath, 866 g AE ha?1) on corn injury, chlorophyll content, shikimate level, plant height and shoot dry weight in non‐glyphosate‐resistant (non‐GR) corn. RESULTS: One week after application (WAA), corn was killed at 3 m from the edge of the spray swath, with injury decreasing to 18% at 35.4 m downwind. Chlorophyll content decreased from 78% at 6 m to 22% at 15.8 m, and it was unaffected beyond 25.6 m at 1 WAA. Shikimate accumulation in corn decreased from 349% at 0 m to 93% at 15.8 m, and shikimate levels were unaffected beyond 25.6 m downwind. Plant height and shoot dry weight decreased gradually with increasing distance. At a distance of 35.4 m, corn height was reduced by 14% and shoot dry weight by 10% at 3 WAA. CONCLUSIONS: Corn injury and other biological responses point to the same conclusion, that is, injury from glyphosate aerial drift is highest at the edge of the spray swath and decreases gradually with distance. The LD50 (the lethal distance that drift must travel to cause a 50% reduction in biological response) ranged from 12 to 26 m among the biological parameters when wind speed was 11.2 km h?1 and using a complement of CP‐09 spray nozzles on spray aircraft. Published 2010 by John Wiley & Sons, Ltd. 相似文献
12.
应用联杯法等室内测定了0.05%氟虫腈杀蚁饵剂对红火蚁的引诱力、毒杀速度及其传导毒杀活性.结果表明,供试饵剂对红火蚁的引诱性、毒杀速度显著优于正舒(对照药剂).红火蚁觅食到供试饵剂的初始时间为2.00 min,与正舒的2.33 min达显著差异;供试饵剂处理后24 h的工蚁死亡率为80.65%,显著高于对照饵剂的50.15%;72 h的工蚁死亡率即达到100%.联杯法测定结果表明,0.05%氟虫腈杀蚁饵剂能通过工蚁的取食和交哺行为进行传导.供试饵剂受药杯中工蚁、幼蚁和蚁后3 d后死亡率均达到100%,显著高于对照饵剂.0.05%氟虫腈杀蚁饵剂引诱性强、对红火蚁具有高胃毒、高传导毒杀活性,可适用于防控入侵红火蚁. 相似文献
13.
蛾龄、温度和相对湿度对草地螟自主飞行能力的影响 总被引：1，自引：0，他引：1
为了更好地了解草地螟(Loxostege sticticalis L.)的迁飞行为规律,为改善和提高其监测预报技术提供进一步的试验依据,本文应用所在实验室研发的昆虫自主飞行测试系统,对不同日龄(1~5日龄)、温度(14、18、22、26和30℃)和相对湿度(20%、40%、60%和80%)条件下的成虫自主飞行活动(飞行倾向、时间和次数)进行了研究。所得的主要结果为:1~2日龄成虫的飞行活动较少,3日龄后明显升高,并随日龄增加而升高。其中4~5日龄的飞行活动显著高于1~2日龄的;在14~30℃条件下,成虫飞行活动随温度的上升而增加,在26℃下达到最大。当温度达到30℃时又下降;在20%~80%湿度条件下,成虫飞行活动随湿度的升高而增加,当湿度达到80%时达到最大,并显著高于其他低湿条件的。对3日龄成虫在22℃、80%湿度条件下持续10h的测试结果表明,测试开始后1h成虫的飞行活动频率相对较高,之后就逐渐下降,在第8h也相对较高,9~10h的飞行活动明显降低。本文就上述结果与草地螟迁飞的关系进行了讨论。 相似文献
14.
Grzegorz Buczkowski 《Pest management science》2023,79(10):4004-4010
BACKGROUND
The Asian needle ant, Brachyponera chinensis, is an invasive ant currently spreading in urban and natural habitats throughout the eastern United States. Recent studies have documented the negative impact of B. chinensis on native ecosystems and human health, yet effective control strategies are lacking. Control difficulties are, in part, due to the unique biology of B. chinensis, which is a predatory ant and a termite specialist. Given that subterranean termites are an important nutritional resource for B. chinensis, the current study evaluated the potential of termite cuticular extract to improve the target-specificity and efficacy of commercial bait used for B. chinensis control.RESULTS
The efficacy of bait augmented with termite cuticular extracts was evaluated in laboratory and field trials. In laboratory assays, B. chinensis colonies were offered granular bait treated with termite cuticular extract. Results demonstrated that the acceptance of commercial bait is significantly increased by the addition of termite cuticular extract or synthetic (Z)-9-pentacosene, a major component of termite cuticular extract. Foraging activity of Asian needle ants was significantly greater on baits augmented with termite cuticular extract or (Z)-9-pentacosene relative to standard bait. Furthermore, bait augmented with termite cuticular extract worked substantially faster relative to standard bait. To evaluate population effects, field studies were conducted in forested areas invaded by B. chinensis. Bait treated with termite cuticular extract scattered on the forest floor provided rapid control of B. chinensis and ant densities throughout the treated plots declined by 98% within 14 days.CONCLUSION
The incorporation of termite cuticular extracts and individual cuticular hydrocarbons such as (Z)-9-pentacosene into traditional baits used for B. chinensis control may offer a novel tool to manage this increasingly problematic invasive ant. © 2023 The Author. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献15.
环境温度变化对异色瓢虫的飞行与运动能力的影响 总被引：1，自引：0，他引：1
研究环境温度变化对异色瓢虫Harmonia axyridis(Pallas)飞行与爬行搜索能力的影响,对合理利用异色瓢虫进行生防控害有重要意义。本研究设置15、25和35℃恒温处理,以及15~35℃连续线性变温和15℃—25℃—35℃跳跃变温处理,利用飞行磨和昆虫行为记录仪测定异色瓢虫成虫对上述温度处理的行为响应。结果表明,异色瓢虫在15℃平均飞行(14.2±1.9)次、累计飞行(1089.6±112.3)m、(98.3±11.6)min,平均飞行速度为(11.2±1.1)m/min,显著高于其他温度;而在35℃平均爬行(26.1±2.1)次,共爬行(719.6±73.2)cm、平均爬行速度为(2.6±0.7)cm/s,且方向改变(101.3±11.2)次,均显著大于其他处理。异色瓢虫在连续跳跃变温条件下的飞行能力与运动搜索能力均显著大于连续线性变温及恒定常温(25℃)对照。本研究表明异色瓢虫在较低温度下的飞行能力较强,而在较高温度下的爬行搜索能力较强。此外,扰动型环境波动可以显著提升异色瓢虫飞行和爬行能力。 相似文献
16.
Anthony W. C. White Robert Martin Duncan C. Stewart John C. Wickham 《Pest management science》1992,34(2):153-162
The development of a mathematical model which, by quantifying the interaction of a population of houseflies with an ageing spray cloud, is capable of predicting the knockdown and kill performance of insecticidal aerosol formulations shown against houseflies, Musca domestica L., will be presented in a series of four separate papers. In this first paper, measurements were made of insecticide collected by houseflies during free flight using a standard room-spray technique. With pressure-packed aerosol formulations where the solvent is the principal change, it was shown that both knockdown and mortality responses of the insects were directly related to dose collected. The process of droplet collection was most significantly influenced by their size and availability, dependent upon the time after spraying, the position of insect release and the activity of individual adult M. domestica. The knockdown or mortality response of the insect to given amounts of insecticide was largely unaffected by the remaining solvent, although, with mineral oil, some inhibition was noted at low mortality levels. The amount of insecticide accumulated by houseflies in their initial flight was of prime importance in determining the overall effect. Flies remaining not knocked down at the end of the exposure period were shown to be so because they had accumulated less toxicant and not necessarily because they were more tolerant of the insecticide. The establishment of a relationship between the number of flies in flight and time after release has provided a key function for incorporation into the model. 相似文献
17.
Daniela T Pezzini Dominic D Reisig G David Buntin Alejandro I Del Pozo-Valdivia Fred Gould Silvana V Paula-Moraes Francis PF Reay-Jones 《Pest management science》2023,79(10):3493-3503
BACKGROUND
Helicoverpa zea, an economic pest in the south-eastern United States, has evolved practical resistance to Bacillus thuringiensis (Bt) Cry toxins in maize and cotton. Insect resistance management (IRM) programs have historically required planting of structured non-Bt maize, but because of its low adoption, the use of seed blends has been considered. To generate knowledge on target pest biology and ecology to help improve IRM strategies, nine field trials were conducted in 2019 and 2020 in Florida, Georgia, North Carolina, and South Carolina to evaluate the impact of Bt (Cry1Ab + Cry1F or Cry1Ab + Cry1F + Vip3A) and non-Bt maize plants in blended and structured refuge treatments on H. zea pupal survival, weight, soil pupation depth, adult flight parameters, and adult time to eclosion.RESULTS
From a very large sample size and geography, we found a significant difference in pupal mortality and weight among treatments in seed blends with Vip3A, implying that cross-pollination occurred between Bt and non-Bt maize ears. There was no treatment effect for pupation depth, adult flight distance, and eclosion time.CONCLUSION
Results of this study demonstrate the potential impact of different refuge strategies on phenological development and survival of an important pest species of regulatory concern. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献18.
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为明确亚洲小车蝗Oedaleus asiaticus成虫飞行肌对其体内能源物质利用的情况,采用室内生化法测定能源物质代谢相关5种酶,即3-磷酸甘油醛脱氢酶(glyceraldehyde phosphate dehydrogenase,GAPDH)、3-磷酸甘油脱氢酶(glycerol-3-phosphate dehydrogenase,GDH)、乳酸脱氢酶(lactate dehydrogenase,LDH)、柠檬酸合成酶(citrate synthase,CS)和3-羟酰辅酶A脱氢酶(3-hydroxyacylCoA dehydrogenase,HOAD)活性的变化,并对群居型和散居型的能源物质利用情况进行比较。结果表明,静止状态下,不同日龄的两型亚洲小车蝗雌成虫体内5种代谢相关酶活性不同,初羽化时酶活性较低,随着成虫日龄增加,酶活性呈上升趋势,多至7日龄或10日龄达到最大,13日龄和20日龄后酶活性略有下降。飞行状态下,成虫体内糖类代谢相关酶的活性在飞行前30 min内升高明显,之后上升缓慢或有所下降,至2 h时酶活性达到最大并趋于稳定;而脂类代谢相关酶和三羧酸循环关键酶的活性则随日龄不断升高并保持在较高水平。群居型亚洲小车蝗体内5种酶活性均显著高于散居型。表明亚洲小车蝗飞行所利用的能源物质包括糖类和脂肪,远距离飞行以脂类能源为主。 相似文献
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