scholarly journals A Phenology Model for Simulating Oobius agrili (Hymenoptera: Encyrtidae) Seasonal Voltinism and Synchrony With Emerald Ash Borer Oviposition

2020 ◽  
Author(s):  
Toby R Petrice ◽  
Leah S Bauer ◽  
Deborah L Miller ◽  
Therese M Poland ◽  
F William Ravlin

Abstract In North America, the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), continues to spread, and its egg parasitoid, Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae), is being released for emerald ash borer biocontrol well beyond their endemic climatic ranges in China. We developed a multiple cohort rate summation model to simulate O. agrili F0, F1, and F2 generations, and emerald ash borer oviposition for examining host–parasitoid synchrony across a north–south gradient from Duluth, MN (latitude 46.8369, longitude −92.1833) to Shreveport, LA (latitude 32.4469, longitude −93.8242). Temporal occurrences of critical day length for O. agrili diapause induction were integrated into the model. We used O. agrili and emerald ash borer trapping data from south central and northwestern Lower Michigan for model validation. Simulations demonstrated that 1) F0 adult emergence consistently occurred 2–5 d before emerald ash borer oviposition began; 2) F1 adult emergence was most synchronized with peak emerald ash borer oviposition compared with other generations; and 3) emerald ash borer oviposition was complete, or near so, when F2 adult emergence was predicted across the north–south gradient. Comparison of O. agrili trap captures with model simulations demonstrated that primarily two adult O. agrili generations (F0 and F1) emerged per year in Michigan and almost all F2 larvae entered diapause despite day lengths longer than critical day length in south central Michigan. Critical day length varied temporally across the north–south gradient during emergence of O. agrili generations. Determining day lengths perceived by O. agrili larvae in the field should improve model realism for examining spatiotemporal variation in O. agrili population dynamics.

2015 ◽  
Vol 148 (3) ◽  
pp. 329-342 ◽  
Author(s):  
Xiao-Yi Wang ◽  
Liang-Ming Cao ◽  
Zhong-Qi Yang ◽  
Jian J. Duan ◽  
Juli R. Gould ◽  
...  

AbstractTo investigate natural enemies of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in northeastern China, we conducted field surveys of ash (Fraxinus Linnaeus (Oleaceae)) trees in semi-natural forests and plantations at variable EAB densities from 2008 to 2013. Our surveys revealed a complex of natural enemies including eight hymenopteran parasitoids and two apparently parasitic Coleoptera, woodpeckers, and several undetermined mortality factors. Parasitoid complex abundance and its contribution to EAB mortality varied with the time of year, type of ash stands, and geographic regions. The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) and the larval parasitoid Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) were frequently observed in Jilin, Liaoning, and Heilongjiang provinces and in Beijing, but not in Tianjin. Spathius agrili Yang (Hymenoptera: Braconidae), however, was more prevalent near Beijing and further south in Tianjin. Larvae of two species of apparently parasitic beetle, Tenerus Laporte (Coleoptera: Cleridae) species and Xenoglena quadrisignata Mannerheim (Coleoptera: Trogossitidae), were also recovered attacking overwintering EAB in Liaoning Province, with Tenerus species being a dominant mortality agent (~13%). Our findings support the need to consider the geographic origin of insect natural enemies for EAB biocontrol, as well as an expanded foreign exploration for EAB natural enemies throughout its native range in Asia.


2016 ◽  
Vol 148 (3) ◽  
pp. 294-306 ◽  
Author(s):  
Lucas E. Roscoe ◽  
D. Barry Lyons ◽  
Sandy M. Smith

AbstractUnder laboratory and field conditions in Ontario, Canada, we explored the natural history of Phasgonophora sulcata Westwood (Hymenoptera: Chalcididae), an indigenous solitary endoparasitoid of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in North America. Adult P. sulcata emergence was ~20.2–23.9 days after host emergence at 21°C, with P. sulcata females emerging an ~5.4–5.8 days before males. Females also represented 61.8 and 67.0% of emerging adults in the two years sampled. Mean adult longevities for males and females of P. sulcata were 23.8±1.10 and 28.9±1.11 days at 21°C, respectively. Mean potential fecundity of P. sulcata at emergence was 55.7±2.9 eggs per female. Based on adult emergence, parasitism at two sites varied from 11.7% to 34.4%. Adult parasitoids were first observed in the field in early June, with peak capture occurring in late June. Parasitism rates in A. planipennis-infested ash trees was not affected by tree height below 360 cm, whereas parasitism was not observed at heights>360 cm. Our results suggest that although mass rearing will be challenging, observed parasitism rates in conjunction with temporal and spatial synchrony indicate that indigenous P. sulcata may be an important source of mortality for A. planipennis populations.


Author(s):  
В.Л. Мешкова ◽  
Т.В. Кучерявенко ◽  
Ю.Е. Скрыльник ◽  
О.В. Зинченко ◽  
А.И. Борисенко

Целью исследования является выявление особенностей распространения ясеневой изумрудной узкотелой златки (ЯИУЗ) в насаждениях Луганской обл. в первый год после ее обнаружения. Обследованы насаждения с наличием в составе ясеня обыкновенного (Fraxinus excelsior L.) и ясеня зелёного, или пенсильванского (Fraxinus pennsylvanica Marsh.), в лесном фонде трёх государственных лесоохотничьих предприятий (Старобельского, Белокуракинского и Сватовского), расположенных к западу от пунктов первого обнаружения ЯИУЗ в Луганской области. Установлено, что ясеневая изумрудная узкотелая златка присутствует практически во всех насаждениях с наличием в составе ясеня зелёного, что составляет 11,1% покрытой лесом площади. В течение 2020 г. ЯИУЗ распространилась на расстояние 32-52 км от первой точки обнаружения. Самая южная точка ее выявления - в районе с. Меловатка, самая западная - в районе с. Донцовка. Учитывая тенденцию распространения ЯИУЗ в юго-западном направлении, можно ожидать ее проникновения в Харьковскую и Донецкую области. Ясеневая изумрудная узкотелая златка заселяет в основном ясень зелёный, а у ясеня обыкновенного - поросль, деревья в насаждениях с низкой полнотой, на опушках и по периметру небольших по площади урочищ или лесополос. Средняя плотность личинок ЯИУЗ (±S.E.) в заселенных ветвях ясеня зелёного и ясеня обыкновенного достоверно не отличается (0,6±0,07 и 0,7±0,09 шт./дм2 соответственно). Однако доля образцов ясеня зелёного с наличием жизнеспособных личинок ЯИУЗ (91,4±3,12%; n = 45) была достоверно более высокой, чем ветвей ясеня обыкновенного (76,1±6,29%; n = 82). Вылетных отверстий ЯИУЗ в деревьях ясеня обыкновенного не обнаружено, а дополнительное питание её имаго отмечено только на листве деревьев ясеня зелёного. Наличие поселений ЯИУЗ в деревьях I-II категорий санитарного состояния свидетельствует о высокой агрессивности насекомого. Вопросы динамики состояния заселенных деревьев и выживания личинок ясеневой изумрудной узкотелой златки предстоит исследовать в дальнейшем, особенно относительно ясеня обыкновенного, который присутствует в насаждениях региона на 36,9% покрытой лесом площади. The goal of the research was to reveal the features of the spread of the emerald ash borer (EAB) in the stands of the Luhansk region during the first year after its detection. The stands with the presence of the common ash (Fraxinus excelsior) and the green ash (F. pennsylvanica) in the forest fund of Starobelskoe, Belokurakinskoe, and Svatovskoe Forest and Hunting Enterprises, located to the west of the points of the first detection of EAB in the Luhansk region, were examined. The EAB was found in almost all stands with the presence of green ash in the composition, which comprises 11.1% of the forested area. During 2020, the EAB spread over a distance of 32-52 km from the first detection point. The southernmost point where it was registered is near Melovatka, and the westernmost - is near Dontsovka. Taking into account the tendency of EAB to spread in the southwestern direction, we can expect its invasion to the Kharkiv and Donetsk regions. EAB inhabits mainly green ash, and in common ash it prefers sprouts, trees in the stands with low relative stocking density, and trees at the edges and along the perimeter of small forests or forest belts. The mean density (±S.E.) of EAB larvae in populated branches does not differ significantly for green ash and common ash (0.6±0.07 and 0.7±0.09 larvae/dm2, respectively). However, the proportion of EABcolonized branches of green ash (91.4±3.12%; n = 45) is significantly higher than that of common ash (76.1±6.29%; n = 82). The exit holes of EAB in the trees of common ash were not found. Maturation feeding of EAB was registered only in the trees of green ash. The presence of EAB galleries and larvae in the trees of the 1st and the 2nd categories of health condition (healthy-looking and weakened trees according to the Sanitary Rules in the Forests of Ukraine) indicates the aggressiveness of EAB. The dynamics of the health condition of EAB colonized trees, as well as the survival of its larvae are to be investigated further, especially for the common ash, which proportion in the stands of the region is about 36.9% of forest-covered area.


Author(s):  
Jian J Duan ◽  
Jonathan M Schmude ◽  
Kristi M Larson

Abstract The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), native to Northeast Asia, is the most destructive invasive ash (Fraxinus spp.) pest in the United States. In the present study, we evaluated the effect of exposure of diapausing mature fourth instars (J-shaped larvae, JL) of EAB to cool temperatures, either 1.7 or 12.8°C for 1–9 mo, on their post-chill development including adult emergence, longevity, and lifetime fecundity under standard rearing conditions (26 ± 0.5°C, 16:8 h L:D). In addition, we determined the effect of different stages of the larvae chilled at 12.8°C for 3 mo on the subsequent post-chill development to EAB adults. Findings from the study revealed that a period (≥2 mo) of chill at 12.8°C is required for the termination of the EAB diapause. However, chill treatment of the larvae at the near zero temperature (1.7°C) does not result in the post-diapause larval development to adults, regardless of the chill time (1–9 mo). In addition, our results showed that chill treatment of immature young larvae (L1–L4 prior to JL) results in little production of EAB adults, indicating that EAB diapause predominantly as JL. Findings of this study may be useful to laboratory rearing of EAB from eggs through continuous generations and help us understand the pest’s voltinism resulting from the diapause and post-diapause development under different climatic conditions.


2020 ◽  
Vol 49 (2) ◽  
pp. 391-404 ◽  
Author(s):  
Patrick J Engelken ◽  
Deborah G McCullough

Abstract Extensive ash (Fraxinus spp.) mortality has been reported across much of the area in eastern North America invaded by emerald ash borer (Agrilus planipennis Fairmaire), but indirect effects of emerald ash borer invasion on native forest insects are not well-studied. We assessed cerambycid beetle (Coleoptera: Cerambycidae) species captured in baited cross-vane panel traps during the 2017 and 2018 growing seasons. Traps were placed in 12 riparian forest sites distributed across three watersheds selected to represent the temporal gradient of the emerald ash borer invasion from southeastern to southwestern Michigan. Although ash species originally dominated overstory vegetation in all sites, >85% of ash basal area has been killed by emerald ash borer. We captured a total of 3,645 beetles representing 65 species and five subfamilies. Species assemblages in southeast sites, with the longest history of emerald ash borer invasion, differed from those in south central and southwest Michigan, which were similar. These differences were largely due to three species, which accounted for >60% of beetle captures in southeast Michigan. Associations among site-related variables and beetle captures indicated cerambycid species assemblages were associated most strongly with abundance and decay stage of coarse woody debris. During both years, >90% of cerambycid species were captured by mid-summer but seasonal activity differed among and within tribes. Numbers of beetles captured by canopy and ground traps were similar but species richness was higher in canopy traps than ground traps. Results suggest inputs of emerald ash borer-killed ash can have temporally lagged, secondary effects on cerambycid communities.


2009 ◽  
Vol 141 (1) ◽  
pp. 40-52 ◽  
Author(s):  
D. Barry Lyons ◽  
Peter de Groot ◽  
Gene C. Jones ◽  
Roger Scharbach

AbstractSticky-band trapping experiments were undertaken in 2003–2006 to examine the host-seeking behaviour of the emerald ash borer, Agrilus planipennis Fairmaire, in woodlots in southwestern Ontario, Canada. The female proportion of A. plannipennis emerging from host logs ranged from 0.414 to 0.582. Landings on sticky-band traps varied more with the female proportion, ranging from 0.392 to 0.889, with the majority in the upper range, suggesting behavioural differences between the sexes. Correlations between landing density and tree size measured as diameter at breast height were positive or showed no relationship. In some locations more beetles were captured on the south side of the tree than on the north side; however, there was no difference between these cardinal directions at other locations. Numbers of captured beetles were never significantly greater on the north side of boles. We observed greater landing densities of adults of both sexes on traps on trees along the edges of woodlots than on trees within the woodlots. When given a choice under natural conditions, beetles landed almost exclusively on host trees (Fraxinus pennsylvanica Marsh. (Oleaceae)) rather than on other common trees species (Carya ovata (Mill.) K. Koch (Juglandaceae), Tilia americana L. (Tiliaceae), and species of Acer L. (Aceraceae)) found in the same woodlots. Our data suggest that A. planipennis make host-selection decisions while in flight rather than landing randomly. Implications for monitoring A. plannipennis using sticky-band traps and understanding its host-seeking behaviour are discussed.


Forests ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 659 ◽  
Author(s):  
David Jennings ◽  
Jian Duan ◽  
Paula Shrewsbury

The emerald ash borer, Agrilus planipennis Fairmaire (EAB), is an invasive beetle that has caused widespread mortality of ash trees in North America. To date, four parasitoids have been introduced in North America for EAB biological control, including the egg parasitoid Oobius agrili Zhang & Huang (Hymenoptera: Encyrtidae). Monitoring EAB egg parasitism is challenging because female beetles oviposit in bark crevices and EAB eggs and O. agrili are small (<1 mm in diameter). Consequently, multiple methods have been developed to recover this parasitoid. Here we compared two methods, visual surveys and bark sifting, used to monitor establishment of O. agrili in Maryland, USA. From 2009 to 2015, a total of 56,176 O. agrili were released at 32 sites across the state. In 2016, we surveyed nine of the study sites for O. agrili establishment using both methods. We compared the amount of time spent searching for eggs separately in each method, and also analyzed the effects of years-post release, total number of parasitoids released, and median month of release, on percent parasitism of EAB eggs, and the percentage of trees per site with parasitized EAB eggs. We found that visually surveying ash trees for EAB eggs was more efficient than bark sifting; the percent parasitism observed using the two methods was similar, but visually surveying trees was more time-efficient. Both methods indicate that O. agrili can successfully establish populations in Maryland, and June may be the best month to release O. agrili in the state. Future research should investigate EAB phenology in the state to help optimize parasitoid release strategies.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 262
Author(s):  
Molly A. Robinett ◽  
Therese M. Poland ◽  
Deborah G. McCullough

Emerald ash borer (EAB), (Agrilus planipennis Fairmaire), first identified in 2002 in southeast Michigan, has caused catastrophic ash (Fraxinus spp.) mortality in forests within the core of the invasion and has spread to 35 states and five Canadian provinces. Little is known about persistence and densities of EAB populations in post-invasion sites after most ash trees have died. We monitored EAB populations from 2014 to 2016 using double decker (DD) traps set in the midst of white ash (F. americana) trees in 30 post-invasion sites in southeast and south-central Michigan. Two DD traps were deployed at each site. One trap had a dark green upper prism and light purple lower prism, both baited with cis-3-hexenol lures. The other had two dark purple prisms baited with cis-3-hexenol on the upper prism and Manuka oil on the lower prism. In 2014 and 2016, size and condition of ash trees were recorded and area of live white ash phloem was estimated in an 18-m-radius plot centered around each of the DD traps. Area of live white ash phloem per site ranged from approximately 24 to 421 m2 in 2014 and from 24 to 411 m2 in 2016. Canopy condition of live white ash trees generally improved; 65% and 89% of the trees had healthy canopies (<20% dieback) in 2014 and 2016, respectively. Traps in 28, 29 and 30 of the sites captured a total of 580, 585, and 932 EAB adults in 2014–2016, respectively. Area of live ash phloem explained relatively little of the variation in total EAB captures in all three years. Low trap catches, along with relatively stable canopy conditions and continued abundance of live white ash, indicate that EAB populations remain below the carrying capacity of the sites, and ash phloem availability is not a limiting factor for EAB abundance. Further monitoring to track both EAB dynamics and tree condition is needed to determine the long-term outlook for white ash in these sites.


2020 ◽  
Vol 9 (3) ◽  
pp. 164-175
Author(s):  
A.Yu. SARAN ◽  
◽  
M.V. SOKOLOV ◽  

The purpose of the article is to study the biography of B.M. Gordon as a successful security officer in the 1920-s and 1930-s. He worked his way up the career ladder from a junior investigator to the head of regional divisions – territorial bodies of the VChK/GPU/OGPU/NKVD and the legal residency of the INO GUGB of NKVD in Germany. Having started his chekist service in the Orel province, he served in the South – Central Asia, in the North – in Arkhangelsk province,in the capital of the USSR, and in the capital of Nazi Germany – Berlin. Gordon fought with the white guards and evicted the dispossessed peasants, controlled the Soviet military and gathered information about the armies of foreign countries; he managed to work at both Soviet and party work. Finally, the energetic work and successful career led Boris Moiseyevich Gordon to his death, when in 1937, J.V. Stalin decided to destroy completely all the former operational leadership of the state security agencies, replacing it with new personnel.


EPPO Bulletin ◽  
2021 ◽  
Author(s):  
G. Schrader ◽  
R. Baker ◽  
Y. Baranchikov ◽  
L. Dumouchel ◽  
K. S. Knight ◽  
...  

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