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1.
Robert S. Nofemela 《Entomologia Experimentalis et Applicata》2010,136(3):281-289
The potential for using synthetic sex pheromone traps as a simple and practical method of monitoring population densities of insect pests has been investigated in many crop systems. Yet, factors enabling the forecast of infestations based on pheromone trap catches are not fully understood. This study tested the prediction that high survival of immature stages of the target pest is a pre‐requisite for trap catches to correlate well with future infestations on the crop. The influence of parasitoids, as an important natural mortality factor of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), larvae and pupae in South Africa, on the ability of pheromone traps to forecast infestations was investigated continuously at weekly intervals over 6 years on unsprayed cabbage. During late October–May, when parasitism levels were high (≥50%), infestations and trap catches were significantly lower than during low parasitism (<50%) observed during June–early October. Because infestations were negatively related to parasitism level, trap catches correlated with infestations better when observations were made in the same week during periods of high parasitism. Conversely, when survival of P. xylostella immature stages was high due to low parasitism levels, trap catches correlated with future infestations well for up to 2 weeks. Thus, trap catches can be used to forecast infestations during September–October, a period that coincides with high P. xylostella infestations as a consequence of low natural control by parasitoids. This is the first study to show that the ability of pheromone trap catches to forecast infestations depends on survival of the immature stages of the target pest. 相似文献
2.
The migration of cereal aphids and the time of their arrival on winter cereal crops in autumn and spring are of particular importance for plant disease (e.g. barley yellow dwarf virus infection) and related yield losses. In order to identify days with migration potentials in autumn and spring, suction trap data from 29 and 45 case studies (locations and years), respectively, were set‐off against meteorological parameters, focusing on the early immigration periods in autumn (22 September to 1 November) and spring (1 May to 9 June). The number of cereal aphids caught in a suction trap increased with increasing temperature, global radiation and duration of sunshine and decreased with increasing precipitation, relative humidity and wind speed. According to linear regression analyses, the temperature, global radiation and wind speed were most frequently and significantly associated with migration, suggesting that they have a major impact on flight activity. For subsequent model development, suction trap catches from different case studies were pooled and binarily classified as days with or without migration as defined by a certain number of migrating cereal aphids. Linear discriminant analyses of several predictor variables (assessed during light hours of a given day) were then performed based on the binary response variables. Three models were used to predict days with suction trap catches ≥1, ≥4 or ≥10 migrating cereal aphids in autumn. Due to the predominance of Rhopalosiphum padi individuals (99.3% of total cereal aphid catch), no distinction between species (R. padi and Sitobion avenae) was made in autumn. As the suction trap catches were lower and species dominance changed in spring, three further models were developed for analysis of all cereal aphid species, R. padi only, and Metopolophium dirhodum and S. avenae combined in spring. The empirical, cross‐classification and receiver operating characteristic analyses performed for model validation showed different levels of prediction accuracy. Additional datasets selected at random before model construction and parameterization showed that predictions by the six migration models were 33–81% correct. The models are useful for determining when to start field evaluations. Furthermore, they provide information on the size of the migrating aphid population and, thus, on the importance of immigration for early aphid population development in cereal crops in a given season. 相似文献
3.
The lower temperature threshold for take-off in Sitobion avenae obtained from an analysis of daily 12·2 m suction trap catches was 16°C. In the laboratory, the take-off threshold for S. avenae was 17·5°C in increasing temperatures, but 19°C when aphids were kept at constant temperatures for a short period of time. The equivalent thresholds were both 20·5°C for Metopolophium dirhodum. Over a period of 16 h no S. avenae took-off from plants at 10°C, 70% at 15°C and all within 16 h at 20°C. It was concluded that suction trap catches can be used to compare the temperature thresholds for take-off of both different species and morphs of a species of aphid. Emigrants of Rhopalosiphum padi, but not of M. dirhodum, took-off at a higher temperature than the alate exules. High winds were found to delay but not inhibit take-off both in the field, and in the laboratory, using both artificial and plant substrates. All aphids eventually flew, even from favourable hosts. It was concluded that adverse weather conditions will delay but not prevent cereal aphid migration in early summer. 相似文献
4.
Aude Vialatte Manuel Plantegenest Jean‐Christophe Simon Charles‐Antoine Dedryver 《Agricultural and Forest Entomology》2007,9(4):337-346
1 Integrated management of crop pests requires the identification of the appropriate spatial scale at which colonization processes occurs. We assessed, by coupling demographic and genetic methods, the relative contribution of local and transient migrants of the grain aphid Sitobion avenae to wheat field colonization in spring. 2 We examined, during two consecutive years, the daily colonization of wheat by aphid migrants and compared this with daily aphid flight monitored by a local 12.2‐m suction trap. The genetic profiles of aphids landing on crops were compared with those of both flying aphids caught by the suction trap and local populations from arable crops and hedgerows. 3 In the first year, we observed: (i) a strong correlation between aphids colonizing the crop and those moving within the crop and a close genetic similarity between aphids from these samples and (ii) a high level of genetic differentiation between these aphids and populations from local cereals and field margins. In the second year, the number of migrants recorded on the wheat was three‐fold higher than in the previous year, and less correlated with that recorded by the suction trap. This was associated with a lack of genetic differentiation between all samples. 4 This variation in the colonization processes resulted mainly in an abrupt increase in abundance of genotypes from local over‐wintering sites in 2004. This suggests that, despite the long range dispersal potential of the grain aphid, outbreak risks could be mainly determined at a local scale, encouraging the design of relatively small management units. 相似文献
5.
Suction trap catches for the period 1969 to 1984 were used to develop a forecasting system for M. dirhodum. This was achieved by using the strong relationships that exist between: a) suction trap catches of Metopolophium dirhodum at Broom's Barn and populations of the aphid in fields near Norwich, and b) winter and spring temperatures and the time when the crop became unsuitable for this aphid. This forecasting system was tested in 1985, 1986, 1987 and 1988 and successfully forecast early in the season that it would not be necessary to apply aphicides in 1987 and 1988. The use of this forecasting system would have correctly indicated that aphicide application against this aphid was unnecessary in 9 out of the 16 seasons from 1969 to 1984. 相似文献
6.
A. Gallardo R. Ocete M. A. López L. Maistrello F. Ortega A. Semedo F. J. Soria 《Journal of Applied Entomology》2009,133(8):626-632
This study aimed at elaborating a forecasting tool of the phenology of the serious pest Lobesia botrana in Southwestern Spanish vineyards, by analysing data on male catches in sex pheromone traps recorded over a 12‐year period. Our data confirmed the minor importance of the first generation which appears during flowering time, both in terms of male trap catches and damage of L. botrana to the inflorescences. Therefore, data related to the first flight were not further processed, although they were considered for the computation of degree‐days of the following generations. The outcome of the elaboration of temperature accumulations and data on male captures for the second and third flights was a statistically acceptable linear behaviour obtained by properly transforming the variables. The models established proved to be efficient and may represent a useful tool to improve the efficacy of integrated pest management strategies targeting L. botrana in the studied region. 相似文献
7.
T. Steinger G. Goy H. Gilliand T. Hebeisen J. Derron 《The Annals of applied biology》2015,166(3):410-419
We compiled data from the Swiss seed certification programme for the country‐wide incidence of viruses in seed potato crops for the years 1989–2012. Model selection techniques were used to regress year‐to‐year variation in the incidence of potato viruses – largely dominated by Potato virus Y (PVY) – in three susceptible varieties against the abundance of virus vectors (winged aphids), obtained in a suction trap, to identify the most important vector species. The ultimate aim of this study was to develop a decision‐support system capable of forecasting virus spread during the current season using trap data of aphid flights. The average virus incidence in the varieties Bintje, Sirtema and Charlotte varied considerably among years, ranging from 1.0% in 2009 to 13.6% in 1989 (N = 150–611 seed lots per year). A linear regression model including the cumulative sums (until mid‐June) of two aphid species (Brachycaudus helichrysi and Phorodon humuli) as predictor variables for virus disease was remarkably well supported by the data (R2 = 0.86). Similarly, using counts of B. helichrysi alone resulted in a good model fit (R2 = 0.81). Cross‐validation revealed high predictive accuracy of the model. Although prediction root mean squared errors (RMSE) calculated for different timings of forecasts were high for extremely early forecasts, they rapidly declined for forecasts conducted by the end of May (i.e. 2–4 weeks after potato emergence). Winter temperature (January–February) was positively correlated with the abundance of B. helichrysi in early summer as well as with post‐harvest virus incidence. Remarkably, the abundance of Myzus persicae, often considered the main vector of PVY, was not correlated with virus incidence. Taken together, our analysis suggests that the early migrating aphid B. helichrysi, rather than M. persicae, is the main vector of PVY in Switzerland, and that suction trap data are useful for the design of decision‐support systems aimed to optimise virus control in seed potato production. 相似文献
8.
Jabraeil Razmjou Shirzad Ramazani Bahram Naseri Gadir Nouri Ganbalani Hooshang Rafiee Dastjerdi 《Applied Entomology and Zoology》2011,46(4):455-461
The English grain aphid, Sitobion avenae (Fabricius), is a severe pest of wheat plants in temperate countries. Therefore, we carried out primary screening to assess
the resistance or susceptibility of 23 commonly grown wheat varieties to this aphid at greenhouse and laboratory conditions
in Iran. Also, population attributes of this aphid were evaluated on six wheat varieties, namely Saysonz, Arta, Moghan3, Zagros,
Sardari and Shirodi. The aphids were colonized on the Hirmand wheat variety in a growth chamber at 20 ± 1°C, 60 ± 5% R.H.
and a photoperiod of 14:10 (L:D). The tested varieties were grouped into three major classes including A (e.g., Shirodi, Falat
and Moghan2), B (e.g., Sardari, Zagros and Tagan) and C (e.g., Arta, Saysonz, Moghan3 and Pishtaz). Also, the results of the
life history traits showed that the developmental time of nymphal stage ranged from 7.5 days on Zagros to 10.8 days on Saysonz.
The intrinsic rate of increase (r
m
) of S. avenae varied from 0.133 (day−1) on Saysonz to 0.210 (day−1) on Shirodi. Jackknife estimates of other population parameters on these varieties were evaluated. As a result, our findings
showed that the varieties Saysonz, Arta and Moghan3 were partially resistant against S. avenae, whereas Shirodi, Zagros and Sardari were relatively susceptible. 相似文献
9.
Sitobion avenae is the most abundant aphid that infests the ears of winter wheat in central Europe. Control of this pest will benefit from prediction of its maximum abundances on ears. We attempted to predict the maximum numbers of this species infesting the ears using earlier counts of this species in ears and on leaves using data collected in the Czech Republic in 2002–2014. The numbers of aphids on particular leaves and the ears were recorded at weekly intervals. The maximum numbers infesting the ears were significantly related to aphid counts on the ears made 1 week, 2 weeks and even 3 weeks before the peak. A regression based only on plots where there were aphids (non‐zero aphid counts) recorded 3 weeks prior to the peak resulted in a critical number of ≥0.44 aphids/ear, which if exceeded resulted in a harmful maximum abundance of ≥5 aphids/ear at the peak. We also regressed maximum numbers infesting ears on numbers of S. avenae on leaves recorded 1, 2 and 3 weeks after earing, which all resulted in reliable predictions. Regression of maximum abundance on non‐zero aphid counts on the leaves in week 3 after earing revealed a critical number of ≥0.59 aphids/tiller. Zero aphid counts resulted in only 3% of cases of a harmful maximum abundance in ears. Using records of the numbers on flag leaves, which make up 58% of the S. avenae population present on the foliage, also provided reliable predictions of maximum abundance in ears. Predicting maximum numbers of aphids from earlier records of the numbers of aphids on leaves or ears is thus possible. The prediction may be further improved by increasing the precision with which the numbers of aphids initially infesting the crop are estimated. 相似文献
10.
V. Marius Aurelian Maya L. Evenden Gary J.R. Judd 《Entomologia Experimentalis et Applicata》2012,145(2):102-114
Recent introduction of Synanthedon myopaeformis (Borkhausen) (Lepidoptera: Sesiidae) into organic apple‐growing areas of Canada has stimulated research on semiochemical‐based management of this European pest. Replicated, small‐plot (0.16 ha) experiments were conducted to compare sex pheromone, 3Z,13Z‐octadecadienyl acetate (10 mg), Concord grape juice (300 ml), or their combination, as mass‐trapping lures at trap densities equivalent to 12.5, 25, 50, and 100 traps ha?1. Total numbers of male and female moths removed from test plots increased significantly with trap density in all juice‐based mass‐trapping experiments. In pheromone mass‐trapping experiments, however, total catches of males did not increase significantly as trap densities were increased and catches appeared to plateau with 25–50 traps ha?1. With pheromone‐based mass‐trapping, significantly fewer males were caught in pheromone‐baited assessment traps at the centre of each mass‐trapping plot than in identical traps in untreated plots. This reduction is indicative of significant trap interference or trap ‘shut‐down’. Increasing the density of juice‐based mass‐trapping had no effect on catches of male or female moths in juice‐baited assessment traps, indicating a short range of attraction and lack of interference between juice traps. Pheromone‐ and juice‐based mass trapping removed similar numbers of males at each trap density tested, respectively, but summed catches of males and females were greatest with juice baits. Combining pheromone and juice into a single mass‐trapping treatment (50 traps ha?1) did not significantly increase catches of males or females relative to either treatment alone. If a practical bisexual mass‐trapping system is going to be developed for S. myopaeformis, then identification of volatile kairomones in Concord grape juice may be useful. 相似文献
11.
J. N. Oakley‡ S. A. Ellis M. Watling† K. F. A. Walters‡ J. E. B. Young† 《Agricultural and Forest Entomology》2005,7(3):211-218
Abstract 1 Recommended and reduced rate applications of pirimicarb and alpha‐cypermethrin were applied to winter wheat crops to control summer infestations of grain aphid (Sitobion avenae) and rose‐grain aphid (Metopolophium dirhodum). 2 Aphid numbers were assessed weekly and the yield response to treatment application was compared with accumulated aphid days on the crop. 3 Responses to aphicide treatment varied between sites according to variations in the subsequent development of aphid populations under varying weather conditions and differential pressures from aphid natural enemies. 4 Alpha‐cypermethrin treatment reduced spider density at most sites, and also resulted in a resurgence of aphid populations at three sites. 相似文献
12.
13.
Krista L. Ryall Jeffrey G. Fidgen Peter J. Silk Taylor A. Scarr 《Entomologia Experimentalis et Applicata》2013,147(2):126-131
The invasive emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a major pest of ash trees, Fraxinus spp., in its introduced range in North America. Field studies were conducted to quantify the efficacy of traps baited with kairomone and pheromone lures for early detection of A. planipennis infestation. A trapping experiment demonstrated that green traps baited with the kairomone (3Z)‐hexenol detected at least one adult A. planipennis in 55.3% of plots with ‘nil to low’‐density infestations and in 100% of plots with ‘moderate to high’‐density A. planipennis infestations. Mean trap captures increased significantly with increasing infestation density. In terms of the optimal number of traps per plot, when one (3Z)‐hexenol‐baited trap was placed per plot, the trap detected populations in 62% of the plots with ‘low to moderate’‐density infestations through branch sampling. Detectability was increased to 82% when two traps were placed per plot. Finally, addition of female‐produced (3Z)‐lactone pheromone to traps significantly increased detection rates at both the trap and plot level, as compared with traps baited with the host volatile, (3Z)‐hexenol, alone (88 vs. 60%, respectively). Our results are the first to demonstrate the efficacy of baited green sticky traps for detecting low‐density A. planipennis infestations, particularly when the (3Z)‐lactone pheromone is used. This combination is therefore recommended for development of early‐detection protocols against A. planipennis. 相似文献
14.
Genetic population structure of sugarcane aphid,Melanaphis sacchari,in sorghum,sugarcane, and Johnsongrass in the continental USA
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Raul F. Medina Scott J. Armstrong Kyle Harrison 《Entomologia Experimentalis et Applicata》2017,162(3):358-365
In 2013, an outbreak of Melanaphis sacchari Zehntner (Hemiptera: Aphididae) was reported in sorghum in Texas, USA. Although this aphid has been reported in the continental USA for nearly a century, its occurrence was limited to Florida and Louisiana sugarcane. After 2013 and within just 3 years M. sacchari was reported in almost all sorghum growing regions from south central to southeastern states in the USA. Sorghum fields in affected areas have sustained considerable losses. This aphid has also been reported on Johnsongrass and other feral grasses. The speed at which this aphid has spread raises serious concerns about future infestations. Many aphid species present genetically distinct populations when feeding on different host plants. Thus, it was hypothesized that the recent outbreak in sorghum could be explained by a recent introduction of a sorghum‐specialized genotype. In this study, we genetically characterized M. sacchari in three of its most common host plants – sorghum, sugarcane, and Johnsongrass – across its geographic distribution in the continental USA. Although M. sacchari specimens were grouped within three genetically distinct clusters, we did not find evidence of host plant or geographic population structure. Our characterization of the genetic structure of this pest provides baseline data aimed to help explain its recent outbreak in sorghum, as well as information that may aid in the design of sustainable control strategies. 相似文献
15.
Development and optimisation of a sex pheromone lure for monitoring populations of saddle gall midge,Haplodiplosis marginata
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Charlotte Rowley Tom W. Pope Andrew Cherrill Simon R. Leather G. Mandela Fernández‐Grandon David R. Hall 《Entomologia Experimentalis et Applicata》2017,163(1):82-92
Saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae), is a sporadic pest of cereals in Northern and Central Europe and is of increasing importance in the UK. Recently, the major component of the sex pheromone produced by adult female H. marginata was reported to be 2‐nonyl butyrate. The importance of absolute configuration on attractiveness, the effects on trap catches of the addition of minor pheromone components, dispenser type, and pheromone loading are described in the development of an optimised pheromone lure with which to trap H. marginata males. In analyses of volatiles collected from virgin female H. marginata by gas chromatography (GC) coupled with electroantennographic recording (EAG) from the antenna of a male H. marginata, two EAG responses were observed. Analyses by coupled GC‐mass spectrometry (MS) indicated these were due to 2‐nonyl butyrate and a trace amount (1%) of 2‐heptyl butyrate. A similar trace amount of 2‐nonanol was detected in GC‐MS analyses but this compound did not elicit an EAG response when the synthetic compound was tested, whereas the other two compounds did. These three compounds were not observed in collections of volatiles made from male H. marginata. The 2‐nonyl butyrate was shown to be the (R)‐enantiomer. In field trapping tests (R)‐2‐nonyl butyrate was at least 10× more attractive to male H. marginata than the racemic compound, and the (S)‐enantiomer was unattractive. Addition of the potential minor components individually or together at the naturally occurring ratios did not increase or reduce the attractiveness of the lure. Polyethylene vials and rubber septa were equally effective as pheromone dispensers, lasting for at least 5 weeks in the field in the UK, although laboratory tests indicated release from the former was more uniform and more likely to last longer in the field. Increasing loading of pheromone in the dispenser increased attractiveness. Traps baited with polyethylene vials containing 0.5 mg of (R)‐2‐nonyl butyrate are recommended for monitoring H. marginata and these are far more sensitive than water or sticky traps currently used for monitoring this pest. 相似文献
16.
Sex pheromone of the cloaked pug moth,Eupithecia abietaria (Lepidoptera: Geometridae), a pest of spruce cones
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H. L. Wang G. P. Svensson J. Jakobsson E. V. Jirle O. Rosenberg W. Francke O. Anderbrant J. G. Millar C. Löfstedt 《Journal of Applied Entomology》2015,139(5):352-360
The sex pheromone of the cloaked pug moth, Eupithecia abietaria Götze, an important cone‐feeding pest in spruce seed orchards in Europe, was investigated. Chemical and electrophysiological analyses of pheromone gland extracts of female moths and analogous analyses of synthetic hydrocarbons and epoxides of chain length C19 and C21 revealed (3Z,6Z,9Z)‐3,6,9‐nonadecatriene (3Z,6Z,9Z‐19:H) and 3Z,6Z‐cis‐9,10‐epoxynonadecadiene (3Z,6Z‐cis‐9,10‐epoxy‐19:H) as candidate pheromone components, which were found in a gland extract in a ratio of 95 : 5. In field trapping experiments, conspecific males were only attracted to a combination of 3Z,6Z,9Z‐19:H and the (9S,10R)‐enantiomer of 3Z,6Z‐cis‐9,10‐epoxy‐19:H. The (9R,10S)‐enantiomer was not attractive, which is in agreement with studies on other Eupithecia species, for which males have only been attracted by the (9S,10R)‐enantiomer of epoxides. Subsequent experiments showed that E. abietaria males were attracted to a wide range of ratios of the two active compounds and that trap catches increased with increasing dose of the binary blend. A two‐component bait containing 300 μg 3Z,6Z,9Z‐19:H and 33 μg of the (9S,10R)‐enantiomer of 3Z,6Z‐cis‐9,10‐epoxy‐19:H was efficient for monitoring E. abietaria in spruce seed orchards in southern Sweden, where this species has probably been overlooked as an important pest in the past. With sex pheromones recently identified for two other moths that are major pests on spruce cones, the spruce seed moth, Cydia strobilella L., and the spruce coneworm, Dioryctria abietella Denis & Schiffermüller, pheromone‐based monitoring can now be achieved for the whole guild of cone‐feeding moths in European spruce seed orchards. 相似文献
17.
Sampling for aphids by traps and by crop inspection 总被引:1,自引:0,他引:1
The catches of thirty aphid genera and species during 3 years in a suction trap at 40 ft and on a yellow cylindrical sticky trap at 5 ft at Rothamsted and Broom's Barn are tabulated. Suction-trap catches were the more consistent but both were more effective at recording the first seasonal immigration of Myzuspersicae (Sulz.) and Aphis fabae Scop, than the British Sugar Corporation crop-inspection scheme. The catches show the differential attraction to yellow by different species, the effects of local vegetation, and the seasonal distribution of aphids that are crop pests or potential vectors of viruses. 相似文献
18.
Daily suction trap samples at a height of 12·2 m collected throughout the year, winter egg and ‘spring’ population counts on the spindle tree, Euonymus europaeus, and initial infestations of the black bean aphid, Aphis fabae, on field bean, Vicia faba, crops are available from Southern England since 1970. In different areas, estimates of the sizes of the autumn migrations, the over-wintering egg populations, the spring fundatrigeniae and the spring migrations, have been used to forecast field bean crop infestation levels which, in turn, project subsequent trap catches of alatae. The forecasts of crop infestation become progressively more accurate from the autumn migration to the following spring migration, accounting for 28%, 54%, 54% and 64% of the variance respectively. In areas where traps are sited, the spring migration trap samples give the most accurate estimate of the size and timing of crop infestation. Autumn trap catches are particularly useful as very early forecasts of likely very large or very small populations on field beans about 8 months later, but otherwise they lack precision. Egg sampling in winter provides a considerably more accurate forecast approximately 5 months before crop infestations. In spring (May), fundatrigeniae sampled on spindle are most useful for predicting time of migration, and provide approximately 2 weeks' warning for insecticide application, if needed. Finally, trap sampling of the spring migration provides the latest estimate of both the sizes of crop infestations and the timing of insecticide treatment. The E. europaeus and aerial sampling systems are complementary, the traps providing systematic, continuous information and the E. europaeus samples greater detail. Combined, they can provide excellent long-term fore-warning of the need for chemical control and short-term warning of control timing. Forecasts have been 90% correct in eight years out of nine. The error in the ninth year may be due to immigration from the European mainland. 相似文献
19.
Machine vision algorithm for whiteflies (Bemisia tabaci Genn.) scouting under greenhouse environment
L. O. Solis‐Sánchez J. J. García‐Escalante R. Castañeda‐Miranda I. Torres‐Pacheco R. Guevara‐González 《Journal of Applied Entomology》2009,133(7):546-552
One of the main problems in greenhouse crop production is the presence of pests. Detection and classification of insects are priorities in integrated pest management (IPM). This document describes a machine vision system able to detect whiteflies (Bemisia tabaci Genn.) in a greenhouse by sensing their presence using hunting traps. The extracted features corresponding to the eccentricity and area of the whiteflies projections allow to establish differences among pests and other insects on both the trap surfaces and dust generated artefacts. Because of whiteflies geometrical characteristics, it was possible to design an efficient (related to manual counting) machine vision algorithm to scout and count units of this pest within a greenhouse environment. These algorithm results show high correlation indexes for both, sticky screens (R2 = 0.97) and plant leaf situations (R2 = 1.0). The machine vision algorithm reduces the scouting time and the associated human error for IPM‐related activities. 相似文献
20.
D. B. Zheng G. Hu F. Yang X. D. Du H. B. Yang G. Zhang G. J. Qi Z. L. Liang X. X. Zhang X. N. Cheng B. P. Zhai 《Journal of Applied Entomology》2014,138(1-2):67-77
Migratory behaviour in insects correlates with reproductive development in females, and migration often occurs during the pre‐reproductive stage of adults. The relationship between ovarian development and population status of the white‐backed planthopper Sogatella furcifera (Horváth) and the brown planthopper Nilaparvata lugens (Stål) was evaluated. Females of both species were captured in rice fields and light traps and then dissected in double‐season rice‐farming regions of southern China. The ovarian development of S. furcifera and N. lugens was divided into five levels, following previous studies. The population statuses of both species were examined based on the ovarian development of female adults caught in rice paddies. The ovarian development in N. lugens females caught in light traps mostly ranged from level I to level II, whereas that in S. furcifera females caught in light traps mostly ranged from level I to level III. During peak immigration, ovarian development in N. lugens females was mainly at level II, whereas that in S. furcifera females was mainly at level II and sporadically at level III. During peak emigration, both S. furcifera and N. lugens showed level I ovarian development. The temporal dynamics of ovarian development in light trap catches revealed that (i) significant emigration and partial immigration periods occur in S. furcifera, with ovarian development mainly at level I and sporadically from level II to level III and (ii) numerous immigrants of N. lugens were detected during sedentary and local breeding periods. The temporal dynamics of ovarian development provides more information than does the paddy population. Thus, this study proposes another method for pest forecasting, which is more precise and efficient than conventional forecasting methods such as light trap catching and monitoring population dynamics in rice fields. 相似文献