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自动监测装置用温室粉虱和蓟马成虫图像分割识别算法 总被引:6,自引:5,他引:1
为了监测温室黄瓜作物虫害种类、数量变化情况以预测虫害发展趋势,该文以粉虱和蓟马为例,提出了一种基于Prewitt、Canny边缘检测算子分割和SVM(support vector machine)的温室粉虱和蓟马诱虫板的图像识别算法。该方法利用HSI(Hue-Saturation-Intensity)颜色空间的I分量与L*a*b*颜色空间的b分量二值图像中害虫目标与背景的高对比性,再分别相应地利用Prewitt算子和Canny算子进行单头害虫边缘分割,再经过形态学处理,最后融合这两幅二值图像完成单头害虫区域的提取。然后提取害虫的5个形态特征(面积、相对面积、周长、复杂度、占空比)及9个颜色特征(Hue-Saturation-Value颜色空间、HSI颜色空间、L*a*b*颜色空间各分量的一阶矩),并对这14个特征参数进行归一化处理,将特征值作为SVM的输入向量,进行温室粉虱和蓟马的诱虫板图像识别。通过分析比较不同向量组合的BP(back propagation)与SVM的害虫识别率、4种不同SVM核函数的害虫识别率,发现颜色特征向量是粉虱和蓟马识别的主成分,且SVM的识别效果优于BP神经网络、线性核函数的SVM分类性能最好且稳定。结果表明:平均识别准确率达到了93.5%,粉虱和蓟马成虫的识别率分别是96.0%和91.0%,能够实现温室害虫的诱虫板图像识别。该研究可以为虫害的监测与预警提供支持,为及时采取正确的防治措施提供重要的理论依据。 相似文献
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基于SVM和区域生长结合算法的南方主要蔬菜害虫分类识别 总被引:4,自引:4,他引:0
该文基于支持向量机(support vector machine,SVM)与区域生长结合算法,设计了对黄曲条跳甲、烟粉虱、小菜蛾、蓟马这四类蔬菜害虫进行分类识别的检测算法。该方案将识别过程融入到分割中,采用网格法进行区域生长种子点的选取,简化图像处理的步骤。该文每种蔬菜害虫训练样本图像为60幅,测试样本为40幅。试验展示,基于其形态、颜色特征,该算法可以将南方重大蔬菜害虫正确分割识别出来,对黄曲条跳甲、烟粉虱、小菜蛾、蓟马成功率为分别为96.4%、93.2%、95.4%、98.2%,算法达到了对多种害虫进行分类的效果,有较好的应用前景。 相似文献
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《农业研究与应用》2020,(4)
为了科学指导生产,为澳洲坚果害虫的可持续控制提供科学依据,作者于2016年全年,在广西崇左市龙州县广西南亚热带农业科学研究所澳洲坚果园进行系统调查,研究害虫的群落结构和动态规律。研究结果表明,澳洲坚果害虫群落包括7目43科104种,其中鳞翅目、半翅目、缨翅目害虫为优势种群。蝽象类(主要是茶翅蝽和稻绿蝽)、荔枝异形小卷蛾、桃蛀螟、玳灰蝶海南亚种、茶黄蓟马是主要害虫,直接影响澳洲坚果的产量和品质,是生产上防治的重点。澳洲坚果害虫群落与气候和人工活动息息相关,每年的3-9月害虫发生的种类最多,数量较大,是加强综合防治的关键时期。在防治实践中,应注意保护天敌,保护果园生物多样性。 相似文献
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该文基于支持向量机(support vector machine,SVM)与区域生长结合算法,设计了对黄曲条跳甲、烟粉虱、小菜蛾、蓟马这四类蔬菜害虫进行分类识别的检测算法。该方案将识别过程融入到分割中,采用网格法进行区域生长种子点的选取,简化图像处理的步骤。该文每种蔬菜害虫训练样本图像为60幅,测试样本为40幅。试验展示,基于其形态、颜色特征,该算法可以将南方重大蔬菜害虫正确分割识别出来,对黄曲条跳甲、烟粉虱、小菜蛾、蓟马成功率为分别为96.4%、93.2%、95.4%、98.2%,算法达到了对多种害虫进行分类的效果,有较好的应用前景。 相似文献
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基于SPOT/VGT NDVI的大区域农作物空间分布 总被引:1,自引:0,他引:1
随着遥感技术在农业上的广泛应用,及时准确掌握小区域农作物长势和分布的方法相对成熟,但对于省级以上的大区域而言,进行作物遥感测量涉及数据、耗费时间和经费等问题,而中国的农业普查制度又存在时效性的问题。以江苏省为研究区,利用SPOT/VGT NDVI长时间序列数据作为农作物分布研究的底图,分别与研究区农业普查数据和野外调查样方数据进行农作物空间分布的统计回归分析和对比,结果表明:对于大区域而言,SPOT/VGT NDVI长时间序列数据对农业作物生长期特征监测有较好地反应,其逐旬的时间分辨率可以弥补空间分辨率的不足,可有效地对农作物长势进行动态监测;农业普查数据、野外调查样方与SPOT/VGT NDVI时间序列分类结果结合进行回归分析,基本可以满足空间分布情况的调查研究,相对于遥感分类法和传统抽样调查等方式,该方法可以高效率低成本地掌握大区域农作物空间分布情况。 相似文献
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提出我国应及时开展农业环境普查,阐述我国开展农业环境普查的重要性、紧迫性,提出了农业环境普查的工作重点、普查内容、普查技术路线、组织原则、普查前期准备技术内容。 相似文献
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西花蓟马成虫在日光温室内的分布和日活动规律 总被引:1,自引:0,他引:1
利用蓝色粘虫板在山东省青州市高柳镇日光温室内研究了西花蓟马(Frankliniella occidentalis)成虫在2009年3月下旬茄子植株上的分布和日活动规律。结果表明,西花蓟马成虫数量在日光温室内由北向南依次减少,北边平均每日诱集量为65.3头·组-1,中间为40.0头·组-1,南边为20.4头·组-1,南北蓝板每日平均诱集量间存在显著差异。日光温室内东西方向上西花蓟马成虫分布表现为由中间向东西两边逐渐增多。在垂直方向上,西花蓟马成虫在茄子所有叶片上均有分布。蓝板对西花蓟马成虫的诱集量从7:00开始逐渐增多到15:00达到最大值,而后逐渐减少,每天有1个活动高峰。另外,蓝板南面(330.6头·d-1)诱集量显著高于北面(242.2头·d-1),东面(343.8头·d-1)显著高于西面(208.0头·d-1)。 相似文献
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Teulon DA Davidson MM Hedderley DI James DE Fletcher CD Larsen L Green VC Perry NB 《Journal of agricultural and food chemistry》2007,55(15):6198-6205
On the basis of structural and/or aroma analogies to known thrips (Thysanoptera: Thripidae) lures, 35 compounds (18 pyridine derivatives, 13 benzene derivatives, and 4 other compounds), consisting of both synthetic and naturally occurring compounds, were screened for their ability to bring about increased thrips capture in field experiments using water traps in Canterbury, New Zealand. Most of the thrips caught were New Zealand flower thrips (NZFT) (Thrips obscuratus) or onion thrips (OT) (Thrips tabaci). The greatest increase in capture for NZFT (158 times for female symbol cf. to water control) was for the known lure ethyl nicotinate, a 3-pyridyl ester. Ethyl isonicotinate, the 4-pyridyl regioisomer of ethyl nicotinate, not previously reported as a thrips lure, provided the greatest increases in capture for OT (31 times) of any of the compounds tested, significantly more than ethyl nicotinate. Other 4-pyridyl carbonyl compounds, including ethyl 4-pyridyl ketone, also increased OT capture significantly. The natural floral compound cis-jasmone, which increased trap capture of NZFT (female symbol 42 times, male symbol 25 times) but not OT, is reported as a thrips lure for the first time. 相似文献
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孤雌生殖是西花蓟马(Frankliniella occidentalis)繁殖的一种重要方式。前期研究发现,西花蓟马在高温下,雌性的存活率远大于雄性。为探究高温处理后仅有雌性西花蓟马孤雌产雄的情况下其后代建立种群的可能性,试验设定:高温(45℃,2 h)处理西花蓟马单个雌性个体,分别进行孤雌产雄生殖后,雄性子代(F1代)与其母系回交产生F2代;高温(45℃,2 h)处理西花蓟马多个雌性个体,进行孤雌产雄生殖后,雄性子代(F1代)与亲代多个雌性个体共存情况下进行交配产生F2代。两组处理模式下建立F2代实验种群生命表。结果表明,上述两种处理模式,母代雌性个体与子代雄性个体交配后均可产生后代,雄性F1代与其母系回交产生的F2代的雌雄性比为1.05∶1;与亲代多个雌性个体共存下交配产生的F2代性比为1.55∶1。雄性F1代与其母系回交产生的F2代的平均单雌产卵量(F)和内禀增长率(rm)显著小于与亲代多个雌性个体共存下交配产生的F2代(P0.05);各龄期的平均发育历期、平均产卵前期和平均总产卵前期2个繁殖力参数以及净生殖率(R0)、平均世代周期(T)2个种群参数,前者则比后者长(P0.05);另周限增长率(λ)两者之间无显著差异。研究表明西花蓟马在孤雌产雄状态下仍然可以在短期建立种群,具有较强的抗高温能力和繁殖能力,为其成功入侵奠定了生态学基础。 相似文献
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Flufenerim, a novel insecticide acting on diverse insect pests: biological mode of action and biochemical aspects 总被引:1,自引:0,他引:1
Ghanim M Lebedev G Kontsedalov S Ishaaya I 《Journal of agricultural and food chemistry》2011,59(7):2839-2844
A new chemical compound was tested for its insecticidal activity against several major insect pests. The compound, called "flufenerim", has a core pyrimidine structure and an unknown mode of action and showed potent activity against the sweet potato whitefly Bemisia tabaci (Gennadius), the green peach aphid Myzus persicae (Sulzer), and the African cotton leafworm Spodoptera littoralis (Boisduval); however, it did not show any activity against two thrips species: western flower thrips Frankliniella occidentalis (Pergande) and tobacco thrips Thrips tabaci (Lindeman). The compound was relatively potent against the three tested pests and caused mortality rates that reached up to 100% at concentrations under 10 mg of active ingredient (ai) L(-1). The action of the compound was very fast, and mortality was observed within 48 h after exposure of the insects to treated leaves. A unique characteristic of this compound is its very short residual activity, which approximates to 4 days after application under laboratory conditions and to 2 days under outdoor conditions for both B. tabaci and S. littoralis. Although this new compound's mode of action is yet unknown, its rapid and potent action against sap-sucking pests suggests that it acts on a very important target site in the insect body and possibly could be applied very close to harvesting. 相似文献
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Davidson MM Perry NB Larsen L Green VC Butler RC Teulon DA 《Journal of agricultural and food chemistry》2008,56(15):6554-6561
In a search for chemical lures to manage the cosmopolitan crop pest western flower thrips (WFT), Frankliniella occidentalis, a Y-tube olfactometer was used to screen 20 compounds, including 18 4-pyridyl compounds. Comparison of Y-tube results for New Zealand flower thrips (NZFT), Thrips obscuratus, with field trapping data for ethyl nicotinate and ethyl isonicotinate, suggested that the minimum attractive dose (MAD) of an odor compound, where significantly ( p < 0.05) more than 50% of thrips walked up the odor-laden arm, provided a measure for selecting compounds to evaluate for potential lure efficacy in the field. Eighteen synthetic 4-pyridyl compounds were tested on female WFT in a Y-tube olfactometer and four 4-pyridyl carbonyl compounds had MADs lower than the known WFT attractants p-anisaldehyde (MAD 10 (-3) microL) and ethyl nicotinate (10 (-2) microL): methyl isonicotinate (10 (-6) microL), ethyl-2-chloropyridine-4-carboxylate (10 (-6) microL), ethyl isonicotinate (10 (-4) microL) and methyl 4-pyridyl ketone (10 (-5) microL). The suitability of MAD for selecting compounds for further evaluation of practical lure efficacy is discussed. Comparisons of activities within homologous series of esters and ketones showed that attractant activity decreased with chain length. 4-Formyl pyridine was an attractant at a dose of 10 (-5) microL, but was repellent at higher doses (10 (-2)-10 degrees microL). 相似文献
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A variety of naturally occurring aldehydes common in plants have been evaluated for their insecticidal activity and for phytotoxicity to postharvest fruits, vegetables, and grains. Twenty-nine compounds were initially screened for their activity against aphids on fava bean leaf disks. Application under reduced pressure (partial vacuum) for the first quarter of fumigation increased insecticidal activity severalfold. The 11 best aldehydes were assayed against aphids placed under the third leaf of whole heads of iceberg lettuce using the same two-tier reduced-pressure regime, which caused no additional detriment to the commodity over fumigation at atmospheric pressure. Phytotoxicity to naked and wrapped iceburg lettuce, green and red table grapes, lemon, grapefruit, orange, broccoli, avocado, cabbage, pinto bean, and rice at doses that killed 100% of aphids was recorded for three promising fumigants: propanal, (E)-2-pentenal, and 2-methyl-(E)-2-butenal. These three compounds have excellent potential as affordable postharvest insect control agents, killing 100% of the aphids with little or no detectable harm to a majority of the commodities tested. Preliminary assays indicate that similar doses are also effective against mealybugs, thrips, and whitefly. 相似文献
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Summary As part of a project to assess the U.S. Asiatic Cotton Germplasm Collection as a source of genes for pest resistance, forty-three accessions of Gossypium arboreum L. were evaluated for resistance to thrips. Thrips, Thysanoptera spp., are a minor, but widespread pest on cotton, G. hirsutum L. and G. barbadense L. Accessions were planted in free-choice field tests in 1988, 1989, and 1990 at the Cotton Branch Experiment Station, Marianna, Arkansas. Damage ratings, based on a scale of 0 (no damage) to 7 (severe damage), were made approximately one month after planting. Relative score was computed by dividing the rating of each accession by the rating of the reference, G. hirsutum Stoneville 506. The relative score averaged over all G. arboreum accessions by year varied with the year, but was less than 100 (relative score for Stoneville 506) in each case. When data were combined for all three years, twenty-five accessions were significantly better than Stoneville 506. Introgression of the better accessions into G. hirsutum is now in progress.Abbreviations NPGS
National Plant Germplasm System
- STV 506
G. hirsutum Stoneville 506 相似文献
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《Agricultural and Forest Meteorology》1987,40(3):215-231
A method for calculating the light extinction probability caused by a forest canopy is presented. With the calculation procedure, it is possible to examine the effect of crown shape, stand density and spatial distribution of trees on the spatial distribution of light extinction probability or on the total shaded area caused by the canopy. At low sun elevations, the momentary projection area of a single crown is greater the more vertically extended the crown is, if the crown volume is held constant. When a longer time period is concerned, the area where the average extinction probability exceeds some arbitrary value is greatest for umbrella-like, horizontally extended crowns. The same is true for a single tree and for a forest stand. When the stand density is low or the tree crown is narrow, the spatial distribution of trees has only a small effect on the amount of shaping; the total amount of shading in random distribution is almost the same as in systematic distribution. In a stand where the total horizontal projection area of crown cones is high, the spatial distribution of trees should be systematic for effective light interception. 相似文献