Pest Management Decisions Research Articles

Environmental and biological drivers of flight initiation in a sporadic pest, Rutherglen bug, Nysius vinitor Bergroth (Hemiptera: Orsillidae)

Flight initiation is fundamental to insect dispersal. Insights into the meteorological and environmental drivers of flight initiation, and their relative importance, can therefore help determine the conditions under which mass dispersal events may occur. In relation to insect pestmanagement, the ability to anticipate such events would allow us to predict mass colonisation of crops and better manage outbreaks of an insect pest. This study insects aims to better predict flight initiation of Rutherglen bug, Nysius vinitor, and thus crop outbreaks originating from over-winter weed hosts. We examined the influence of temperature in combination with sex and the availability of food and water, under controlled environment conditions inside a flight chamber. Most of the variation in flight initiation was explained by temperature. We found that warm temperatures are required for flight initiation: the lower flight threshold was determined as 21 degrees C, the optimum temperature for flight as 25 degrees C and the upper flight threshold as 28 degrees C, fitting a quadratic distribution. However, additional data shows that such thresholds are not limiting: when N. vinitor is under extreme heat stress (35-40 degrees C) for a short period, they have a very high propensity to take-off. The rate of flight initiation was fastest within the first 5 h in both males and females for all tested temperatures. A lack of food and water resulted in a faster take-off rate of males, but had no effect on female flight initiation. Application of our analysis to temperature data in New South Wales (NSW) and Queensland (Qld), Australia, indicates that flight initiation in N. vinitor is likely to be highly seasonal, with very little flight activity expected in winter in eastern Australia. We found a longer suitable flight period and a greater number of suitable flight days per month in Qld compared to NSW. Such estimates could be used to inform regional pest arrival forecasts, integrated pest management decisions and the development of dispersal simulation models for this pest.

Monitoring Tyrophagus putrescentiae (Acari: Acaridae) With Traps in Dry-Cured Ham Aging Rooms.

Methyl bromide is the most effective fumigant for controlling the mold (or ham) mite, Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), the most significant pest of dry-cured ham. However, methyl bromide is being phased out of use. Therefore, integrated pest management (IPM) methods should be developed to help control mites in dry-cured ham plants. The foundation of a successful IPM program is an effective monitoring program that provides information on pest presence and abundance over time. By using food-baited traps fabricated from disposable petri dishes and a dog food-based bait, mite activity over time and space was monitored in five dry-cured ham aging rooms from three commercial processing facilities that differed in their fumigation frequencies. Weekly sampling of the mite was conducted from June 2012 to September 2013. There were significant differences in the average weekly trap captures in all facilities, especially before and after fumigation, with the majority of mites in traps prior to fumigation. Mite numbers had a pattern of sharp decline after fumigation, followed by a steady increase until the next fumigation. Average trap captures varied due to trap location over the study period at all study sites, indicating that traps could be used to identify specific locations within an aging room where mite infestation of hams was more likely to occur. These findings can inform facility managers of mite population changes that can be used as one factor toward making pest management decisions and assessing the impact of fumigation or other pest mitigation actions.

Spatial distribution pattern and sequential sampling plans for Bactrocera oleae (Gmelin) (Dip: Tephritidae) in olive orchards

The distribution of adult and larvae <em>Bactrocera oleae</em> (Diptera: Tephritidae), a key pest of olive, was studied in olive orchards. The first objective was to analyze the dispersion of this insect on olive and the second was to develop sampling plans based on fixed levels of precision for estimating <em>B. oleae</em> populations. The Taylor’s power law and Iwao’s patchiness regression models were used to analyze the data. Our results document that Iwao’s patchiness provided a better description between variance and mean density. Taylor’s <em>b</em> and Iwao’s <em>β</em> were both significantly more than 1, indicating that adults and larvae had aggregated spatial distribution. This result was further supported by the calculated common <em>k</em> of 2.17 and 4.76 for adult and larvae, respectively. Iwao’s a for larvae was significantly less than 0, indicating that the basic distribution component of <em>B. oleae</em> is the individual insect. Optimal sample sizes for fixed precision levels of 0.10 and 0.25 were estimated with Iwao’s patchiness coefficients. The optimum sample size for adult and larvae fluctuated throughout the seasons and depended upon the fly density and desired level of precision. For adult, this generally ranged from 2 to 11 and 7 to 15 traps to achieve precision levels of 0.25 and 0.10, respectively. With respect to optimum sample size, the developed fixed-precision sequential sampling plans was suitable for estimating flies density at a precision level of D=0.25. Sampling plans, presented here, should be a tool for research on pest management decisions of <em>B. oleae</em>.

Draft Genome Sequences of 18 Strains of Pseudomonas Isolated from Kiwifruit Plants in New Zealand and Overseas.

In this paper, we present the draft sequences of 18 genetically diverse Pseudomonas strains isolated from kiwifruit plants in New Zealand and overseas, including a number that are currently not fully characterized. These sequences will aid in the diagnosis of Pseudomonas on kiwifruit for future pest management and border security decision-making.

Interactive effects of pests increase seed yield.

Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides.

Pesticide use and cooperative management of natural enemy habitat in a framed field experiment

Shifting agricultural land management to one that promotes the use of biological control alongside insecticide spray, requires two key elements: 1) habitat for natural enemies provided by non-crop area within the agricultural landscape, and 2) judicious use of insecticides by farmers. However, barriers to adoption may include low levels of knowledge regarding pests and natural enemies, and the difficulties associated with coordinating among community members. The acts of practicing cautious spraying and of leaving aside land as non-crop habitat (NCH) for natural enemies incur private costs for benefits shared by the community. In this study we tie together several objectives within the analysis of a framed field experiment built around pest management decisions in a smallholder agricultural context. We present results from a within-subjects design (multiple treatments per game group) that estimates a decision model which links behavior back to characteristics of the game, the players, and their group. We examine the relative role these sets of characteristics have in explaining variations in the modeled decisions, including how farmers respond to a nudge (a flat subsidy for allowing land to sit as non-crop habitat) to promote natural enemy services on the land. We observe that group-level characteristics appear to have the greatest roles in explaining how decisions by individuals are made. That is to say, the decision of whether to adopt greater use of NCH has more to do with those around the farmer than the traits of the farmer him or herself. From a policy point of view, it is a signal that (if such game outcomes have any bearing on farm-level decisions) conventional data tools (such as household-level data products from household surveys or censuses) may be inadequate in evaluating appropriate incentives, and newer approaches that identify social networks and neighbor/community interactions may be important.

Biological control adoption in western U.S. orchard systems: Results from grower surveys

As part of a USDA Specialty Crop Research Initiative project to enhance biological control (BC) in western U.S. orchard systems, we surveyed walnut growers in California and pear growers in Oregon and Washington about their pest management decision-making and use of BC practices. Seventy-six percent of pear growers and 54% of walnut growers reported using one or more BC practices. BC users were more likely to minimize factors that harm natural enemies than enhance natural enemy habitats or release commercially produced natural enemies. Walnut growers with more education and orchard experience, as well as larger and more diversified operations, were more likely to use BC practices. Walnut and pear growers with some certified organic acreage, who considered environmental impacts when making pest management decisions, and who used selected pest management practices (pheromone mating disruption and degree-day calculations for codling moth control) were more likely to use BC practices. BC users relied more heavily on industry publications and university-based sources of pest management information, compared with non-users. The perceived benefits of BC adoption included reduced reliance on pesticides, reduced production costs, environmental protection, protection of beneficial insects, and improved worker safety and human health. The perceived barriers to BC adoption included lack of knowledge, questionable effectiveness, high cost, and lack of recommendation by pest management consultants. Our research not only contributes to the literature on the adoption of sustainable agricultural practices, but also can inform future BC research and outreach by offering insight into who uses BC practices and assessment of perceived adoption benefits and barriers.

Diel Patterns of Colaspis brunnea and Colaspis crinicornis (Coleoptera: Chrysomelidae) in Southeastern Nebraska.

A field study was conducted to increase our understanding of diel activity patterns of Colaspis brunnea (F.) and Colaspis crinicornis Schaeffer (Coleoptera: Chrysomelidae) in key crop habitats. Within 24-h periods, C. brunnea was sampled in clover fields (primarily red clover, Trifolium pretense (L.), with some sweet clover, Melilotus officinalis (L.) Pallas, and downy brome, Bromus tectorum (L.)) and soybean, Glycine max (L.) Merrill, fields, using a sweep-net, while whole-plant-count sampling was used to monitor C. crinicornis densities in field corn, Zea mays (L.). Sweep-net captures of C. brunnea were significantly greater at night than during the day, suggesting possible vertical movement within the canopy during a 24-h period. Colaspis crinicornis densities on corn plants were fairly constant throughout a 24-h period, but beetle activity (e.g., walking, mating) was significantly greater at night than during the day. Results suggest that both Colaspis species may be exhibiting similar increases in activity at night that facilitates movement from more protected to more exposed areas within a habitat. It is unclear what mechanisms drive this diel pattern, but vegetation architecture and associated interactions with environmental conditions may play a role. Sweep-netting in clover or soybean fields and use of whole-plant-counts in cornfields were effective sampling methods for Colaspis adults. However, because activity and behaviors of Colaspis beetles were influenced by time of day in this study, use of a consistent sampling time within a diel period would be recommended for future population studies or integrated pest management decision-making.

Economic Analysis for Commingling Effects of Insect Activity in the Elevator Boot Area.

Boot areas in commercial grain elevators and feed mills contribute to commingling of insects with grain that moves through the elevator leg. A partial budget and stochastic dominance model were developed to improve pest management decision-making and risk analysis assessment from commingling effects of insect activity in the boot area. Modified pilot-scale bucket elevator legs, containing residual wheat or corn, were infested with varying insect pest densities prior to clean grain transfers. Appropriate grain discounts were applied to grain samples obtained from clean grain transfers over either: 1) insect-free and untreated boots, 2) infested and untreated boots, or 3) infested and chemical-treated (β-cyfluthrin) boots. The insect-free boots simulated performing clean-out of the boot area. Partial budget analysis and stochastic dominance modeling indicated that boot sanitation (cleanout) about every 30 d, avoiding costly grain discounts from insect commingling, is the preferred choice. Although chemical spray treatments of the empty boot may reduce insect populations of some boot residual grains, boot cleanout always had lower and usually zero insect pest populations in the boot residual grain, providing higher facility operational net income without the use of chemicals.

Effects of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) Feeding Injury on Sweet Corn Yield and Quality.

The brown marmorated stink bug, Halyomorpha halys (Stål), is an Asian species that now dominates the stink bug complex in many cultivated crops throughout the mid-Atlantic United States. Sweet corn (Zea mays L.) is a preferred host of H. halys, and the bug can cause kernel injury on developing ears. Currently, there is limited information available on which plant growth stages are most sensitive to H. halys feeding or density of bugs required to cause yield and quality reductions on processing and fresh market sweet corn ears. In 2011 and 2012, sweet corn ears were infested at three different corn growth stages: silking (R1), blister (R2), and milk (R3) at densities of zero, one, three, and five H. halys adults per ear for 7 d. At harvest, four yield measurements were assessed and ears were inspected for quality reductions. The greatest yield loss from H. halys occurred when infestations were initiated during early stages of ear development, and the greatest quality reductions (damaged kernels) occurred during later stages of ear development. A density of one H. halys per ear resulted in levels of kernel damage great enough to cause significant quality reductions. This study highlights the ability of H. halys to cause substantial economic losses in both fresh market and processing sweet corn in a relatively short period of time at low population densities. Therefore, infestations by this insect in sweet corn must be considered when making pest management decisions in regions where it has become established.

Decision making models embedded into a web-based tool for assessing pest infestation risk

Current practices in agricultural management involve the application of rules and techniques to ensure high quality and environmentally friendly production. Based on their experience, agricultural technicians and farmers make critical decisions affecting crop growth while considering several interwoven agricultural, technological, environmental, legal and economic factors. In this context, decision support systems and the knowledge models that support them, enable the incorporation of valuable experience into software systems providing support to agricultural technicians to make rapid and effective decisions for efficient crop growth. Pest control is an important issue in agricultural management due to crop yield reductions caused by pests and it involves expert knowledge. This paper presents a formalisation of the pest control problem and the workflow followed by agricultural technicians and farmers in integrated pest management, the crop production strategy that combines different practices for growing healthy crops whilst minimising pesticide use. A generic decision schema for estimating infestation risk of a given pest on a given crop is defined and it acts as a metamodel for the maintenance and extension of the knowledge embedded in a pest management decision support system which is also presented. This software tool has been implemented by integrating a rule-based tool into web-based architecture. Evaluation from validity and usability perspectives concluded that both agricultural technicians and farmers considered it a useful tool in pest control, particularly for training new technicians and inexperienced farmers.

Assessment of a more conservative stink bug economic threshold for managing stink bugs in Brazilian soybean production

The objective of this study was to assess the stink bug economic threshold for soybean integrated pest management decisions. For this purpose, a replicated experiment was implement in a commercial soybean crop located in Arapongas, Parana State, Brazil, during two crop seasons: 2010/2011 and 2011/12. Treatments consisted of different stink bug densities triggering the application of insecticides, ¼ of the economic threshold (ET) (= 0.5 stink bugs m−1) and ET (= 2 stink bugs m−1), and without applying an insecticide (control). The stink bugs were quantified weekly and all specimens were identified to the species level. At harvest, yield and quality of the seeds were also measured. In all crops, Euschistus heros was the most abundant species. The highest yield and percentage of viable seeds were found in the 'BMX Power RR′ cultivar (indeterminate growth cultivar), indicating a better seed quality. At the end of the experiment, there was no observed difference in yield between different stink bug management thresholds, indicating the effectiveness of the control when adopting ET. This study demonstrates that decreasing the economic threshold increased the number of required insecticide applications, but did not increase yield or bean quality neither the net income when an economic analysis was performed.

Intercrop movement of convergent lady beetle, Hippodamia convergens (Coleoptera: Coccinellidae), between adjacent cotton and alfalfa.

A 2-year study was conducted to characterize the intercrop movement of convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) between adjacent cotton and alfalfa. A dual protein-marking method was used to assess the intercrop movement of the lady beetles in each crop. In turns field collected lady beetles in each crop were assayed by protein specific ELISA to quantify the movement of beetles between the crops. Results indicated that a high percentage of convergent lady beetles caught in cotton (46% in 2008; 56% in 2009) and alfalfa (46% in 2008; 71% in 2009) contained a protein mark, thus indicating that convergent lady beetle movement was largely bidirectional between the adjacent crops. Although at a much lower proportion, lady beetles also showed unidirectional movement from cotton to alfalfa (5% in 2008 and 6% in 2009) and from alfalfa to cotton (9% in 2008 and 14% in 2009). The season-long bidirectional movement exhibited by the beetles was significantly higher in alfalfa than cotton during both years of the study. The total influx of lady beetles (bidirectional and unidirectional combined) was significantly higher in alfalfa compared with that in cotton for both years. While convergent lady beetles moved between adjacent cotton and alfalfa, they were more attracted to alfalfa when cotton was not flowering and/or when alfalfa offered more opportunities for prey. This study offers much needed information on intercrop movement of the convergent lady beetle that should facilitate integrated pest management decisions in cotton utilizing conservation biological control.

Association Between Bagrada hilaris Density and Feeding Damage in Broccoli: Implications for Pest Management

Bagrada hilaris (Burmeister) (Hemiptera:Pentatomidae) has become a serious economic pest of brassica crops in Arizona and southern California. Feeding damage on broccoli can result in excessive seedling mortality and, on established plants, in malformed plants which are not commercially marketable. Although management tactics have been developed for this new pest, a reliable sampling technique for estimating adult density is lacking. Here, we analyzed data from 18 insecticide trials conducted from 2011 to 2014 in plots planted to broccoli to determine if estimates of fresh feeding damage on broccoli plants can be used to forecast B. hilaris densities. The proportion of plants with fresh feeding damage in a plot was significantly affected by year, trial nested within year, number of insecticides applied, and time after insecticide application. Average density of B. hilaris adults per plant in a plot was significantly affected by year, trial nested within year, and number of insecticides applied, while time after insecticide application had a marginal effect on population density. Across plots and years, the proportion of plants with fresh feeding damage was strongly and positively associated with the average number of B. hilaris adults per plant. Our results suggest that sampling young plants for signs of fresh feeding damage will provide a reliable and accurate sampling technique for monitoring B. hilaris in broccoli fields. We recommend that growers and pest control advisers focus their monitoring efforts on sampling broccoli plants for the presence of fresh feeding damage, rather than adults alone, when making pest management decisions. Accepted for publication 10 November 2015. Published 12 November 2015.

Innovations in air sampling to detect plant pathogens.

Many innovations in the development and use of air sampling devices have occurred in plant pathology since the first description of the Hirst spore trap. These include improvements in capture efficiency at relatively high air-volume collection rates, methods to enhance the ease of sample processing with downstream diagnostic methods and even full automation of sampling, diagnosis and wireless reporting of results. Other innovations have been to mount air samplers on mobile platforms such as UAVs and ground vehicles to allow sampling at different altitudes and locations in a short space of time to identify potential sources and population structure. Geographical Information Systems and the application to a network of samplers can allow a greater prediction of airborne inoculum and dispersal dynamics. This field of technology is now developing quickly as novel diagnostic methods allow increasingly rapid and accurate quantifications of airborne species and genetic traits. Sampling and interpretation of results, particularly action-thresholds, is improved by understanding components of air dispersal and dilution processes and can add greater precision in the application of crop protection products as part of integrated pest and disease management decisions. The applications of air samplers are likely to increase, with much greater adoption by growers or industry support workers to aid in crop protection decisions. The same devices are likely to improve information available for detection of allergens causing hay fever and asthma or provide valuable metadata for regional plant disease dynamics.

Insecticidal Seed Treatments in Rice

Rice is the staple food for the majority of the world’s population. Globally, rice is cultivated on an estimated 160 m ha annually [1]. Although the U.S contributes only 2% of world rice production from less than 1% of world’s acreage, the U.S is one of top five global exporters of rice [2]. Insect pests pose a major biotic threat to rice production throughout the world. In the U.S, the rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is the most destructive insect pest of rice [3]. In addition to the RWW, a number of other pests can attack rice during the seedling, vegetative and early reproductive phases of rice development. The importance of these pests varies regionally. In Arkansas, for example, Colaspis sp. can be important pests of young rice and can severely reduce early season stands [4]. In Louisiana and Texas, several Lepidopterans are important, including the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), and the sugarcane borer, Diatraea saccharalis (Lepidoptera: Crambidae). While these pests are not consistently important constraints on yield, they can occasionally cause heavy losses. In contrast, losses from the RWW would probably average 5% or more if fields were not treated and this insect is a key driver of early season pest management decisions [5]. Application of foliar pyrethroid insecticides for weevil management, a practice used since the late 1990’s, has been problematic due to high toxicity of this group of insecticides to aquatic invertebrates, primarily to red swamp crawfish, the major aquaculture commodity cocultivated with rice in rotation systems in Louisiana [6-8]. As alternatives to pyrethroids, two groups of insecticides have been labeled since the mid-2000s as seed treatments in ricethe anthranilic diamide group (active ingredient: chlorantraniliprole; Dermacor X-100®) and the neonicotinoid group (active ingredietns: thiamethoxam; Cruiser Maxx®; clothianidin; Nipsit INSIDE®). These seed treatment insecticides have longer residual activity on RWWs than pyrethroids and are two to three orders of magnitude less acutely toxic to crawfish than pyrethroids [6,7]. The two groups of seed treatment insecticides differ in their activities on their sporadic insect pest complex [9] and in their potency against weevils [10]. The growers’ choice of treatment with neonicotinoid or anthranilic diamide is influenced by the threat of sporadic pests, the relative safety of these insecticide classes on crawfish, and the cost of treatment.

Foraging Behavior of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) First Instar Larvae on Selected Cotton Varieties

The movement, survival, and weight gain of Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) first instar larvae were studied on CB9, CB10 and SR05 cotton varieties under field conditions. The neonate H. armigera were released on the cotton varieties at the squaring stage of the plants and, after a period of 72 hours, the survival, weight gain, and final location of the larvae were observed. While the different cotton varieties had no effect on the survival and weight gain of the larvae, the release locations on the cotton varieties had a significant influence on the larval survival and weight gain. The larvae fed small squares of the cotton varieties were significantly heavier and showed a higher mortality than the larvae fed leaflets and mature leaves. For the cotton varieties in this study, the larvae released on leaflets showed a significantly higher rate of recovery compared to the larvae released on mature leaves and squares. This study also found that that the larvae on leaflets did not move up or downward unlike the larvae on mature leaves and squares. This information on the foraging behavior of larvae on cotton varieties will assist researchers to interpret field data and thereby help with the development of pest management decisions.

Assessing the impact of arthropod natural enemies on crop pests at the field scale.

There are many reasons why it is important that we find ways to conserve, and better utilize natural enemies of invertebrate crop pests. Currently, measures of natural enemy impact are rarely incorporated into studies that purport to examine pest control. Most studies examine pest and natural enemy presence and/or abundance and then qualitatively infer impact. While this provides useful data to address a range of ecological questions, a measure of impact is critical for guiding pest management decision-making. Often some very simple techniques can be used to obtain an estimate of natural enemy impact. We present examples of field-based studies that have used cages, barriers to restrict natural enemy or prey movement, direct observation of natural enemy attack, and sentinel prey items to estimate mortality. The measure of natural enemy impact used in each study needs to be tailored to the needs of farmers and the specific pest problems they face. For example, the magnitude of mortality attributed to natural enemies may be less important than the timing and consistency of that mortality between seasons. Tailoring impact assessments will lead to research outcomes that do not simply provide general information about how to conserve natural enemies, but how to use these natural enemies as an integral part of decision-making.

Spatial distribution and sequential sampling plans for Tuta absoluta (Lepidoptera: Gelechiidae) in greenhouse tomato crops.

The within- and between-plant distribution of the tomato leafminer, Tuta absoluta (Meyrick), was investigated in order to define action thresholds based on leaf infestation and to propose enumerative and binomial sequential sampling plans for pest management applications in protected crops. The pest spatial distribution was aggregated between plants, and median leaves were the most suitable sample to evaluate the pest density. Action thresholds of 36 and 48%, 43 and 56% and 60 and 73% infested leaves, corresponding to economic thresholds of 1 and 3% damaged fruits, were defined for tomato cultivars with big, medium and small fruits respectively. Green's method was a more suitable enumerative sampling plan as it required a lower sampling effort. Binomial sampling plans needed lower average sample sizes than enumerative plans to make a treatment decision, with probabilities of error of <0.10. The enumerative sampling plan required 87 or 343 leaves to estimate the population density in extensive or intensive ecological studies respectively. Binomial plans would be more practical and efficient for control purposes, needing average sample sizes of 17, 20 and 14 leaves to take a pest management decision in order to avoid fruit damage higher than 1% in cultivars with big, medium and small fruits respectively.

Toward anticipating pest responses to fruit farms: Revealing factors influencing the population dynamics of the Oriental Fruit Fly via automatic field monitoring

The Oriental Fruit Fly (OFF), Bactrocera dorsalis (Hendel), is one of most devastating insect pests that have periodically caused serious damage to fruit farms in Taiwan and many countries in the world. In the past, many studies reported that the population dynamics of OFF was partially correlated to the weather and the historical population development of OFF in the field. By making the best use of modern info-communication technologies (ICTs), long-term pest population data and microclimate variables measured with uniquely fine spatiotemporal resolution are now available to reveal the population dynamics of OFF. An analysis of data over three years using the Vector Auto-Regressive and Moving-Average model with eXogenous variables (VARMAX) was proposed to unravel the regulatory mechanism between the population dynamics of OFF and microclimate factors. In addition, the proposed model provides a 7-day forecast for population dynamics of OFF. The accuracy of 7-day risk level forecasting yielded by the proposed model ranges from 0.87 to 0.97, and the average root-mean squared errors of forecasting the population dynamics fall in the interval between 0.31 and 4.95 per day per farm. The proposed forecasting model can allow authorities to gain a better understanding of the dynamics of OFF and anticipate pest-related problems, so they can make preemptive and effective pest management decisions before the real problems occur.