Blue willow beetle explained

The blue willow beetle (Phratora vulgatissima), formerly Phyllodecta vulgatissima, is a herbivourous beetle of the family Chrysomelidae. It is dark with a metallic sheen that ranges from a blue color to bronze. It is distinguished from P. vitellinae by the latter more commonly displaying bronze coloration. European Phratora species can be distinguished based on morphology of female genitalia.[1] The larvae undergo three instar stages from hatching to pupation.[2] This beetle is found throughout Europe and Scandinavia,[3] and occurs in China.[4]

Ecology

The blue willow beetle is found on willow (Salix) species, whose leaves contain low levels of salicylates[5] [6] in fens, carrs and on river banks, but also often in willow short rotation coppice and other agricultural landscapes.[7] It often aggregates on host plants.[8] On Salix cinerea, it prefers and is more common on female than male trees despite higher egg predation exerted by the common flowerbug Anthocoris nemorum on female trees.[9] It is univoltine in Sweden but can produce multiple generations per year in other parts of its distribution range.[10] Proliferation of larvae and egg production varies with vegetation.[11] It overwinters under lichens on trees and under tree bark.[12] Predators of blue willow beetle eggs include A. nemorum and Orthotylus marginalis. Larval predators include A. nemorum, the bug Rhacognathus punctatus, a syrphid fly (possibly Parasyrphus nigritarsis)[13] and the wasp Symmorphus bifasciatus.[14] Adult beetles are parasitized by the wasp Perilitus brevicollis[15] and consumed by R. punctatus.

As a pest

In Europe, the blue willow beetle can become a severe herbivore pest on willows.[16] For plantations of common osier (Salix viminalis), herbivory reducing biomass production by up to 40% has been estimated.[17] It is susceptible to Bacillus thuringiensis tenebrionis and also Spinosad when treatment is applied to affected plants.[18]

Notes and References

  1. 21. 5–7. Sundholm. A.. Studien über die Gattung Phyllodecta Kirby (Col. Chrysomelidae). Opuscula Entomologica. 1956.
  2. Performance of an herbivorous leaf beetle (Phratora vulgatissima) on Salix F2 hybrids: the uimportance of phenolics . Journal of Chemical Ecology. 2013-03-01 . 516–524. 39. 4. 10.1007/s10886-013-0266-3. 23456345. Mikaela. Torp. Anna. Lehrman. Johan A.. Stenberg. Riitta. Julkunen-Tiitto. Christer. Björkman. 1714405 .
  3. Book: Lucht, W. H.. Goecke and Evers Verlag. Die Käfer Mitteleuropas: Katalog. Krefeld. 1987.
  4. 2. 3. 218–224. Chen. S. H.. On the Chinese species of the Chrysomeline genus Phratora. Acta Zootaxonomica Sinica. 1965.
  5. 52. 517–528. Köpf. A.. Rank. N. E.. Roininen. H.. Julkunen-Tiitto. R.. Pasteels. J. M.. Tahvanainen. J.. The evolution of host-plant use and sequestration in the leaf beetle genus Phratora (Coleoptera: Chrysomelidae). Evolution. 1998. 2. 10.1111/j.1558-5646.1998.tb01651.x. 28568343. 24641299. free.
  6. 61. 25–32. Kelly. M. T.. Curry. J. P.. The influence of phenolic compounds on the suitability of three Salix species as hosts for the willow beetle Phratora vulgatissima. Entomologia Experimentalis et Applicata. 1991. 10.1111/j.1570-7458.1991.tb02392.x. 84232264.
  7. 111. 57–62. Kelly. M. T.. Curry. J. P.. The biology and population density of the willow beetle (Phratora vulgatissima [L.]) on Salix viminalis in reclaimed cutaway peat. Journal of Applied Entomology. 1991. 1–5. 10.1111/j.1439-0418.1991.tb00293.x. 86736745.
  8. Spatio-temporal dynamics of willow beetle (Phratora vulgatissima) in short-rotation coppice willows grown as monocultures or a genetically diverse mixture. Agricultural and Forest Entomology. 1999-11-01 . 287–296. 1. 4. 10.1046/j.1461-9563.1999.00039.x. L.. Peacock. S.. Herrick. P.. Brain. 84933651 .
  9. Plant-sex-biased tritrophic interactions on dioecious willow. Kabir. Faisal MD. 2015-04-19. Ecosphere. 5. 12. 153. 10.1890/ES14-00356.1. Moritz. Kim K. Stenberg. Johan A. free.
  10. 2. 1–100. Görnandt. H.. Die Käfergattung Phyllodecta Kirby. Deutsche Entomologische Zeitschrift. 1955. 10.1002/mmnd.19550020102.
  11. Effects of host variety on blue willow beetle Phratora vulgatissima performance . L. Peacock . J. Harris . S. Powers . amp . . 144 . 1 . 2004 . 45–52 . 10.1111/j.1744-7348.2004.tb00315.x.
  12. Phenology and population dynamics of willow beetles (Coleoptera: Chrysomelidae) in short rotation coppice willows at Long Ashton. Kendall. D A. 1996. Biofuels Study.
  13. Book: SPB Publishing. 2: Ecological Studies. 147–171 . P. H. Jolivet . M. L. Cox . Rank. N. E.. Smiley. J. T.. Köpf. A.. Chrysomelidae Biology. Natural enemies and host plant relationships for chrysomeline leaf beetles feeding on Salicaceae. Amsterdam. 1996.
  14. Book: Blüthgen, P.. Akademie Verlag. Die Faltenwespen Mitteleuropas (Hymenoptera, Diploptera). Berlin. 1961.
  15. Plant-mediated effects of different Salix species on the performance of the braconid parasitoid Perilitus brevicollis . J.A. Stenberg . Biological Control . 60 . 2012 . 54–58 . 10.1016/j.biocontrol.2011.09.004.
  16. Uncoupling direct and indirect plant defences: Novel opportunities for improving crop security in willow plantations. J. Stenberg . A. Lehrman . C. Björkman . . 139 . 4. 2010. 528–533 . 10.1016/j.agee.2010.09.013.
  17. Effects of leaf beetle damage on stem wood production in coppicing willow. C. Björkman. S. Höglund. K. Eklund. S. Larsson. amp. . 2 . 2. 2000. 131–139 . 10.1046/j.1461-9563.2000.00058.x. 85412547 .
  18. Helbig. C.. Müller. M.. Landgraf . D. . Insect pests in short rotation coppice in Germany—An overview of their effects, risk potential and control measures . Short Rotation Forestry and Agroforestry: An Exchange of Experience between CDM Countries and Europe . Benwood Project Consortium . 2011 . 46–56 . 10.1.1.432.2300.