Adult Emergence Holes Research Articles

Using Multispectral Data from UAS in Machine Learning to Detect Infestation by Xylotrechus chinensis (Chevrolat) (Coleoptera: Cerambycidae) in Mulberries

The tiger longicorn beetle, Xylotrechus chinensis Chevrolat (Coleoptera: Cerambycidae), has posed a significant threat to mulberry trees in Greece since its invasion in 2017, which may be associated with global warming. Detection typically relies on observing adult emergence holes on the bark or dried branches, indicating severe damage. Addressing pest threats linked to global warming requires efficient, targeted solutions. Remote sensing provides valuable, swift information on vegetation health, and combining these data with machine learning techniques enables early detection of pest infestations. This study utilized airborne multispectral data to detect infestations by X. chinensis in mulberry trees. Variables such as mean NDVI, mean NDRE, mean EVI, and tree crown area were calculated and used in machine learning models, alongside data on adult emergence holes and temperature. Trees were classified into two categories, infested and healthy, based on X. chinensis infestation. Evaluated models included Random Forest, Decision Tree, Gradient Boosting, Multi-Layer Perceptron, K-Nearest Neighbors, and Naïve Bayes. Random Forest proved to be the most effective predictive model, achieving the highest scores in accuracy (0.86), precision (0.84), recall (0.81), and F-score (0.82), with Gradient Boosting performing slightly lower. This study highlights the potential of combining remote sensing and machine learning for early pest detection, promoting timely interventions, and reducing environmental impacts.

Endophytic Development of the Entomopathogenic Fungus Beauveria bassiana Reduced the Development of Galls and Adult Emergence of Leptocybe invasa in Susceptible Eucalyptus

Eucalyptus cultivation in arid regions is limited by the losses caused by the galling wasp, Leptocybe invasa Fisher and La Salle, 2004 (Hymenoptera: Eulophidae); it oviposits below the epidermis of the central veins, mainly on seedlings in nurseries and/or young plants in the field, causing galls where the insects develop. Galls modify the normal circulation of sap in vascular tissues, ultimately affecting the development of infested plants and resulting in slower growth. Eucalyptus genotypes tolerant to water stress are susceptible to L. invasa, and this pest has no effective control methods. Here, we aimed to (i) determine the initial infestation dynamics of L. invasa in Eucalyptus plants inoculated with Beauveria bassiana and (ii) identify any change in the development of galls. B. bassiana-inoculated seedlings were infested with L. invasa. Susceptible plants were unaffected, and gall development was negatively affected at multiple stages. A fungal solution containing B. bassiana reduced gall development and the emergence of L. invasa adults in eucalyptus plants at considerable rates. The total number of adult emergence holes was 89.74% fewer for inoculated plants when compared to uninoculated plants. These results can help develop B. bassiana products to control L. invasa in susceptible eucalyptus plants for improved, sustainable forestry.

Effects of dinotefuran trunk injection against the red-necked longhorn beetle Aromia bungii (Coleoptera: Cerambycidae) in Japanese flowering cherry trees

ABSTRACT The control effects of a commercial-grade dinotefuran formulation “Wood-Star” applied via trunk injection against Aromia bungii larvae infestation in Japanese flowering cherry trees were evaluated. Twenty test trees were injected with this formulation in late April 2019, and the number of larval frass-excretion-holes with newly ejected frass (hereafter “active frass-holes”) in both treated and untreated trees was investigated weekly from April to May in 2019 and 2020. In addition, adult emergence-holes that occurred in 2018, 2019, and 2020 on each tree were counted. The total number of active frass-holes decreased by 21.2% in treated trees and increased by 178.9% in untreated trees within 4 weeks after injection. The insecticidal efficacy of the formulation was estimated as 88.2% based on the decreasing number of active frass-holes in the treated trees. Generalized linear models for the number of active frass-holes and newly occurring emergence holes suggested that dinotefuran treatment decreased the larval activity for at least 4 weeks, resulting in the suppression of emerging adults in the next year of treatment. However, active frass-holes and newly occurring emergence holes were observed in some treated trees in the succeeding year of the treatment. This suggested the possibility that the injection treatment in late April was, at least partially, invalid to control A. bungii larvae that originated from the eggs deposited in the adult reproductive period (June to August) of the treatment year.

Characteristics of the meconia of European egg parasitoids of Halyomorpha halys

Halyomorpha halys is a severe invasive Asian pest worldwide and classical biological control is foreseen as the most promising control method. Egg parasitoids appear to be the most important natural enemies of this pest, especially the Asian hymenopteran Trissolcus japonicus. In the invaded areas, only a few egg parasitoid species have been able to adopt H. halys as a host. Anastatus bifasciatus is the most common native egg parasitoid of H. halys in Europe, but reaches only low levels of parasitization, while several other native species are only occasionally found. Recently, adventive populations have been found both in the USA and in Europe of T. japonicus, and in Italy of a second Asian species, Trissolcus mitsukurii. Species identification based on morphological traits by specialists or by molecular analysis is a crucial step in the management of biological control programs. The ability to identify the genus or species within a narrow guild of egg parasitoids based on adult emergence holes and meconium features can be a simple and useful method to support management efforts. We present here detailed descriptions of the meconium of the most frequent parasitoid species attacking H. halys in Europe and the characteristics of their emergence holes of the adult wasps.

Genetic, spatial, and temporal aspects of decline and mortality in a Fraxinus provenance test following invasion by the emerald ash borer

We report a 6-year study of an irruptive invasion of emerald ash borer (EAB) into a 36-year-old comparison of 60 green ash (Fraxinus pennsylvanica Marsh.) and 5 white ash (F. americana L.) populations. As the infestation progressed, annual measures of EAB injury (density of adult emergence holes on the trunk, crown condition, and mortality) were significantly influenced by genetic effects (population and in some instances family within population), site quality (field blocks), and neighborhood (contagion effects over distances of 5–13 m). At the last measurement, 99% of green ash trees and 87% of white ash were dead, and most of the remaining few trees had badly deteriorating crowns. Although final destruction was nearly complete, the rapidity with which trees were injured and killed was moderated by genetic and site effects and influenced by proximity to infested trees. These facts suggest that some genotypes, especially on favorable sites, will disproportionately survive under future equilibrium conditions with lower densities of ash and EAB in the landscape.

Impact of nitrogen fertilization on Mexican rice borer (Lepidoptera: Crambidae) injury and yield in bioenergy sorghum

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is a serious pest of sugarcane (Saccharum spp.), sorghum (Sorghum bicolor (L.) Moench), corn (Zea mays L.), rice (Oryza sativa L.), and related graminaceous bioenergy crops. A two-year field study was conducted in Jefferson County, TX to examine the impact of nitrogen (N) fertilization on E. loftini infestations and subsequent yields in cultivars of high-biomass and sweet sorghum. In 2013, percentage of bored internodes and number of adult emergence holes per stalk increased with higher N rates; however, only the percentage of bored internodes was impacted by N in 2014. Yields from both years indicated that N rate was positively associated with increases in stalk weight and ethanol productivity, but not sucrose concentration. Because higher N rates were associated with increased yields despite having greater levels of E. loftini injury, our data suggest that increases in yield from additional N outweigh decreases from additional E. loftini injury. Fertilization rates maintained between the recommended 45 and 90 kg N/ha minimize risks of negative area-wide impacts from increased production of E. loftini adults, while still allowing for optimum yields.

Container Wall Porosity and Root Pruning Influence on Swietenia mahogani Root Ball Architecture and Anchorage After Planting

The emerald ash borer (EAB), first discovered in North America in Michigan in 2002, continues to expand its distributional range. Early detection of EAB remains a major caveat in efforts to implement proactive management strategies. Past reports have shown that ash trees infested with EAB have an increased risk of branch failure and other symptoms associated with tree decline. Therefore, early detection efforts could be improved if a suite of tree symptoms—prior to visible signs of EAB infestation—can be identified. Researchers initiated a four-year study in Ohio, U.S. (2009– 2012) to investigate and document symptoms associated with the EAB–ash tree complex in urban sites. The prior history of EAB at the study sites ranged from ash trees with no visible evidence of infestation to those that were infested for more than two years. In trees shown to be recently colonized by EAB, visible signs of infestation, such as adult emergence holes, presence of EAB galleries, bark loss, and canopy loss were not always apparent. However, in EAB-positive trees, there was a significant tendency for the presence of cracks in scaffold branches, branch fractures within the upper canopy, and branch fractures specifically located closer to the union with the stem as opposed to at the branch tip or at the branch’s center of gravity. This study highlights tree symptoms associated with the initial colonization of EAB when host trees are still apparently healthy, which could greatly facilitate future detection efforts for EAB.

Evaluation of Ash Tree Symptoms Associated with Emerald Ash Borer Infestation in Urban Forests

The emerald ash borer (EAB), first discovered in North America in Michigan in 2002, continues to expand its distributional range. Early detection of EAB remains a major caveat in efforts to implement proactive management strategies. Past reports have shown that ash trees infested with EAB have an increased risk of branch failure and other symptoms associated with tree decline. Therefore, early detection efforts could be improved if a suite of tree symptoms—prior to visible signs of EAB infestation—can be identified. Researchers initiated a four-year study in Ohio, U.S. (2009– 2012) to investigate and document symptoms associated with the EAB–ash tree complex in urban sites. The prior history of EAB at the study sites ranged from ash trees with no visible evidence of infestation to those that were infested for more than two years. In trees shown to be recently colonized by EAB, visible signs of infestation, such as adult emergence holes, presence of EAB galleries, bark loss, and canopy loss were not always apparent. However, in EAB-positive trees, there was a significant tendency for the presence of cracks in scaffold branches, branch fractures within the upper canopy, and branch fractures specifically located closer to the union with the stem as opposed to at the branch tip or at the branch’s center of gravity. This study highlights tree symptoms associated with the initial colonization of EAB when host trees are still apparently healthy, which could greatly facilitate future detection efforts for EAB.

Goldspotted oak borer effects on tree health and colonization patterns at six newly-established sites

Newly-established populations of invasive wood-inhabiting insects provide an opportunity for the study of invasion dynamics and for collecting information to improve management options for these cryptic species. From 2011 to 2013, we studied the dynamics of the goldspotted oak borer Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), a new pest of oaks in southern California, at six sites that had been colonized recently. At all sites, the percentage of coast live oaks Quercus agrifolia Née, colonized by A. auroguttatus increased between 2011 (6–33%) and 2013 (23–40%), although beetle densities did not grow rapidly at most sites. From 2011 to 2013, there were minor changes in signs and symptoms of A. auroguttatus infestation (adult emergence holes, bark staining, and evidence of woodpecker foraging), except at one site where an outbreak occurred. At some sites, noticeable negative changes in oak crown health occurred 1 year prior to positive A. auroguttatus population growth. Among sites, most of the A. auroguttatus population density (66–93%) was produced by a small number of heavily-infested trees (= brood trees). Early identification and removal of brood trees in newly-invaded areas could slow the growth of A. auroguttatus populations.

Occurrence and development of Eucryptorrhynchus brandti and E. chinensis (Coleoptera: Curculionidae) on Ailanthus altissima trees subjected to different levels of mechanical damage

Eucryptorrhynchus brandti (Harold) and E. chinensis (Oliver) are herbivores of Ailanthus altissima (Mill.) Swingle (tree of heaven) in China. Eucryptorrhynchus brandti has been recommended as a potential biological control agent of A. altissima in North America. In China, the majority of adults of both species were found on tree trunks 0–5 m above the ground, from May to September. In October and November, most adults were found at the base of A. altissima trees. Trees were subjected to different levels of mechanical injury: very low mechanical injury, one to two 0.015 m2 bark sections were removed; low, two to four bark sections were removed; moderate, 8 to 22 bark sections removed; high, tree was girdled; and extreme, tree was felled and the remaining stump was sampled. Very low and low mechanical injury trees had very few adult emergence holes with few larvae developing beyond the first or second instar after 29 months. The health of these trees remained good. An increase in adult emergence holes occurred in moderately injured trees that appeared as healthy as very low to low mechanically injured trees. This may indicate that only a small increase in tree stress can increase the adult emergence rate and thus hasten a decline in tree health. Moderate, high and extreme mechanically injured trees had significantly more emergence holes/m than very low and low injured trees and late larval stages were present. The development of Eucryptorrhynchus species was more successful the greater the degree of mechanical injury. Based on this study both Eucryptorrhynchus species appear to be secondary pests of A. altissima in China.

Comparative evaluation of six storage methods for postharvest preservation of cowpea grain

Several technologies reputedly minimize losses of stored cowpea grain to bruchid beetles on low resource farms in Africa. Side by side comparison of these different postharvest storage methods can provide the basis for deciding which performs best. We compared six different technologies for cowpea storage: (1) grain mixed with ash; (2) mixed with sand; (3) fumigated with phostoxin; (4) admixed with the stems and leaves of Boscia senegalensis (Pers) Lam ex Poir, a potential botanical insecticide; (5) disinfested using a solar heater, and; (6) hermetically sealed in triple-layer plastic bags. Sampling was done at thirty-day intervals over five months of storage. Counts were made of (i) adult emergence holes, (ii) dead larvae and (iii) surviving bruchid larvae and adults. Controls, which consisted of infested cowpea grain stored in cloth bags, were damaged extensively. Boscia senegalensis-treated grain suffered similar severe damage. All other treatments suppressed bruchid population increases as was evident from the much lower counts of emergence holes and lower numbers of surviving or dead insects.

Factors Affecting Suitability ofQuercus rubraas Hosts forEnaphalodes rufulus(Coleoptera: Cerambycidae)

Epidemic populations of Enaphalodes rufulus (Haldeman), red oak borer, a native longhorned wood boring beetle, were implicated as a major contributor to a recent widespread oak mortality event in the Ozark National Forest of Arkansas. We assessed potential factors affecting suitability of a primary host Quercus rubra L., northern red oak, which experienced dieback and mortality throughout two successive borer cohorts. We sampled trees with various E. rufulus infestation levels during 2001-2003 when populations were at outbreak levels and 2003-2005 when borer numbers were declining. We measured phloem thickness and calculated a vigor index; the ratio of the past 5-yr basal area increment to sapwood area. We also counted established first year larval feeding galleries and outer-bark adult emergence holes and measured surface area of feeding galleries on a subset of Q. rubra to assess the importance of host susceptibility versus suitability. Phloem thickness did not exhibit any patterns among hosts of varying infestation levels and was therefore not likely an important factor limiting larval success. Less vigorous Q. rubra appeared to be the most suitable hosts, although it is unclear whether reduced vigor was initially caused by stress of E. rufulus infestation or environmental factors. Host suitability seems to be more important than host susceptibility, as numbers of initiated galleries were not consistently different among host infestation classes and between both cohorts, whereas numbers of emerging adults did differ predictably among host infestation classes.

Dieback and recovery in poplar and attack by the hornet clearwing moth, Sesia apiformis (Clerck) (Lepidoptera: Sesiidae)

A survey of 801 poplar trees in central east England in 1999 demonstrated a correlation between crown dieback and infestation by hornet clearwing moth (Sesia apiformis), induced by a period of drought in 1995-1996. To determine whether trees colonised by S. apiformis would subsequently deteriorate and die or whether they could recover despite infestation and damage to the stem, all trees in the original survey were re-assessed in 2001, 2003 and 2005. The repeat surveys showed that trees with 70% or less crown dieback in 1999 replaced their canopy and generally improved by 2005, irrespective of the numbers of S. apiformis in the stem, whereas trees that had 75% or more crown dieback in 1999 either died or declined further. The presence of S. apiformis did not prevent tree recovery, and there was little evidence that infestation slowed the rate of recovery. Populations of S. apiformis, measured in terms of the numbers of adult emergence holes visible in the base of the trees, decreased between 2001 and 2005 at the same time as the amount of dieback visible in the canopy of the poplars markedly decreased. However, the fall in numbers of emergence holes at this time reflected a decline in larval establishment 2-3 years earlier, and indicated that the moth population had responded to a more rapid restoration in the internal state of the trees, which was not reflected immediately by the gradual replacement of dead branches and reduction in dieback symptoms.

First host records for the rogadine genera Rogasodes Chen and He and Canalirogas van Achterberg and Chen (Hymenoptera: Braconidae) with description of a new species and survey of mummy types within Rogadinae s. str.

The parasitic wasp genus Rogasodes is recorded for the first time outside mainland China, based on a new species, R. scytaloptericola Quicke and Shaw sp. nov., from Java. Rearing data and host remains associated with the type specimen show that it is a parasitoid of the palm‐feeding drepanid moth, Scytalopteryx elongata (Snellen). Canalirogas sp. aff. balgooyi van Achterberg and Chen is recorded from an unidentified lymantriid on clove trees in Indonesia (Sumatra) and illustrated. Both of these are the first host records for the genera. Rogas spilonotus Cameron is transferred to Canalirogas. A survey of mummy sclerotization and adult emergence holes in the subfamily Rogadinae sensu stricto is presented. The data suggest an early shift to a posterior emergence position, with a strictly dorsal position being largely characteristic of the common genus Aleiodes. Only Aleiodes and a few apparently closely related taxa, including Hemigyroneuron, typically form heavily sclerotized mummies.

Efficacy of Integrating Varietal Resistance and Neem (Azadirachta indica A. Juss) Seed Oil for t,e Management of Callosobruchus maculatus Infesting Bambara Groundnuts in Storage

The efficacies of three rates (0.5, 1.0 and 1.5 mg/20 g seed) of application of neem (Azadirachta indica) seed oil (NSO) in controlling Callosobruchus maculatus infesting stored bambara groundnut were assessed on four local cultivars (Ole, Bakingangala, Bulmono and Jor) with different susceptibilities to bruchid attack. Untreated batches of the cultivars were included to serve as control. Treated and untreated batches were infested with adults of C. maculatus under prevailing storage conditions. Combining application of NSO especially at the rate of 1.5 mg/20 g seed with varietal resistance significantly reduced oviposition and progeny development in C. maculatus. No adult progeny developed in seeds of Bakingangala that were protected with 1.5 mg of oil. Treatment of seeds with NSO at this rate reduced seed damage from 97, 72.3, 58.1 and 87.90.4in unprotected Ole, Bakingangala, Bulmono and Jor to 3.0, 3.4, 0.0 and 18.3%, respectively. The interaction of the strategies also significantly reduced the severity of damage (number of adult emergence holes per seed) and overall susceptibility of the bambara groundnut cultivars. Susceptibility indices (SI) values for unprotected bambara groundnuts were 11.92, 10.52, 9.09 and 11.43 for Ole, Bakingangala, Bulmono and Jor, respectively. Comparable SI values for bambara groundnuts that were treated with NSO at the rate of 1.5 mg/20 g seed were 0.0, 1.12, 0.0 and 2.82 for-Ole, Bakinganpla, Bulmono and Jor respectively.

Semiochemical Cues Used by <I>Pteromalus cerealellae</I> (Hymenoptera: Pteromalidae) to Locate Its Host, <I>Callosobruchus maculatus</I> (Coleoptera: Bruchidae)

Abstract The role of semiochemicals in host location by the parasitoid Pteromalus cerealellae (Boucek) was investigated in Y-tube and three-way olfactometers, by measuring responses to stimuli associated with the cowpea weevil, Callosobruchus maculatus. Orientation of mated parasitoid females was measured in response to five stimuli: live virgin female bruchid beetles, solvent extracts of whole body virgin female bruchids, solvent extracts of the oviposition marking pheromone from a glass substrate, previously infested cowpea seeds with adult emergence holes, and uninfested cowpea seeds. All stimuli elicited significantly better responses than those to blank controls. Female parasitoids that had previous exposure to live, virgin beetles and infested seeds exhibited shorter latency and response times to the stimuli than did naive females. Live, virgin female bruchids and whole body solvent extracts of virgin female bruchids elicited the strongest responses. Comparison of responses in a three-way olfactomet...

Resistance to the Mexican Rice Borer (Lepidoptera: Crambidae) Among Louisiana and Texas Sugarcane Cultivars

A 2-yr study to evaluate Louisiana and Texas sugarcane, Saccharum spp., cultivars for resistance to the Mexican rice borer, Eoreuma loftini (Dyar), was conducted in two locations in Texas, chosen for having different infestation levels. Criteria for assessment of resistance included percentage of bored internodes and adult emergence holes, the latter used to determine the relative impact of each cultivar on the potential areawide buildup or reduction of adult E. loftini populations. A recently released cultivar, HoCP 85-845, seemed to lose a portion of its resistance under heavy E. loftini infestation pressure, suggesting its value only in moderate-to-low infestation conditions. Cultivar CP 70-321 was the most resistant. Results indicated that cultivar LCP 85-384 was significantly (P < 0.05) more susceptible than NCo 310, traditionally the most susceptible cultivar commercially produced in Texas. In 2001, LCP 85-384, which now represents 85% of the production area in Louisiana, had the greatest moth production per hectare (17,052 ± 3,956) under the lower infestation pressure, significantly (P < 0.05) higher than HoCP 85–845 (3,038 ± 2,353). In a portion of the test at the high-infestation location, high levels of sodium and magnesium salt stress (15–30-cm soil depth) were associated with higher E. loftini damage in all cultivars except HoCP 91-555 and CP 70-321.

Influence of carrier solvent on the efficacy of neem (Azadirachta indica A. Juss) seed oil applied for the control of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

The influence of four carrier-solvents (acetone, ethanol, petroleum ether and hexane) on the efficacy of neem (Azadirachta indica A. Juss) seed oil applied at the rate of 0.04 ml/33 ml of cowpea seeds and tested on the cowpea seed bruchid, Callosobruchus maculatus (F.), was assessed under tropical storage conditions. Neem seed oil (NSO) applied in ethanol or hexane, on average, reduced egg-laying, percentage of seeds infested with bruchid eggs, adult progeny development and severity of seed damage (number of adult emergence holes per seed) significantly more than application of NSO in acetone or petroleum ether. Cowpea seeds treated with NSO applied in 0.4 or 0.6 ml of the carrier solvents were, on average, infested significantly less with bruchid eggs than seeds treated with NSO applied in 0.2 ml of the solvents. Adult progeny development decreased as the volume of solvents increased and no adult progeny developed in seeds treated with NSO applied in 0.8 ml of ethanol. Severity of seed damage was significantly lower (1.17) in seeds treated with NSO applied in 0.8 ml than in seeds treated with pure NSO (1.59). Application of NSO in hexane reduced the percentage of seeds damaged by C. maculatus significantly more than application of the oil in petroleum ether and seed damage was lowest in batches of cowpea seeds treated with oil applied in 0.8 ml of the solvents.

Alguns aspectos da biologia do serrador &lt;i&gt;Oncideres impluviata&lt;/i&gt; (Germar, 1824) (Coleoptera: Cerambycidae).

Objetivando determinar alguns parâmetros comparativos da biologia do serrador Oncideres impluviata (Germar, 1824)(Coleoptera: Cerambycidae) sobre angico-vermelho, Parapiptadenia rigida (Benth.) Brenan (Leguminosae-Mimosoidea), em Santa Maria-RS, e sobre capororoca, Rapanea umbellata (Mart. ex D.C.) Mez (Myrsinaceae), em São Sepé-RS, durante o período 1990/92, realizou-se este trabalho. Com paquímetro, mediu-se o comprimento e a largura do orifício de emergência dos adultos do serrador e, o comprimento e o volume da galeria larval-pupal. O. impluviata apresenta orifício de emergência quase circular, desenvolvendo-se em galhos de diversos diâmetros, independente da espécie botânica e, o comprimento da galeria e o volume são similares para as duas espécies botânicas.

Boring Activity on Coniferous Tree Branches by Xylotrechus villioni (Villard) Larvae (Coleoptera: Cerambycidae)

In anAbies homolepis Sieb. et Zucc. forest at Matsumoto, Nagano Pref., cumulative damage byXylotrechus villioni (Villard) (Coleoptera: Cerambycidae) was observed on tree branches. Of the 14 major branches in one sample tree, six had cumulative damage by boring larvae, of which 3 had been bored by multiple larvae. No adult emergence holes were found on the whole tree, suggesting very low survivorship from boring larva to emerging adult. Galleries made by single larvae were often observed to be terminated by a depression apparently carved by a picid woodpecker, suggesting that they are important predators of the cerambycid. The manner of cicatrix formation with phloem tissue over the larval gallery in anAbies veitchii Lindl. branch at Mt. Fuji, Yamanashi Pref. is presented.