Aenasius arizonensis Hayat
(Formerly known as Aenasius bambawalei Hayat).
Systematic position: Insecta, Holometabola, Hymenoptera, Apocrita, Chalcidoidea, Encyrtidae.
Geographical distribution: USA, South-East Asia, Iran, Egypt and Israel.
Morphology: Body of adults compact, about 1.5-2.0 mm in length, shiny black-blue, antennae and legs brown with distal segments darker, wings with only a single, anterior vein.
Life history: Aenasius arizonensis is a solitary endoparasitoid of Phenacoccus solenopsis. Its females prefer 3rd host nymphs, which are more often attacked (74.0–84.0%) than other stages and produce more females, as compared to other host stages. A female parasitoid can produce up to about 100 eggs, and more than one egg may be placed in a single host. A generation can be completed in 2 weeks, the adults living about 4-5 weeks. Phenacoccus solenopsis appears to be the only host.
Economic importance: In many areas A. arizonensis is a major biological control agent of P. solenopsis. It may bring about 90-100% pest control in India, as it did in Israel. The host plant of P. solenopsis affects the life history of A. arizonensis. It attacked more hosts infesting Hibiscus as compared to rates on Ph. solenopsis infesting eggplant, tomato and potato, and the emerging parasites were larger. The controlling effect of A. arizonensis may be disrupted by ants. In India the hyperparasite Myiocnema comperei Ashmead can reduce the numbers of A. arizonensis in late summer, resulting in resurgences of P. solenopsis.
Effect of pesticides: Organophosphates were highly toxic to A. arizonensis, imidacloprid is moderately harmful and neem only slightly toxic after 24 h. Several insect growth regulators were comparatively safe to the parasitoid.
References
Abdin, Z. (and 6 co-authors). 2012. Biological characteristics and host stage preference of mealybug parasitoid Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae). Pakistan Entomologist 34: 47-50.
Aga, M., Tambe, V.J., Nagarare, V.S. and Naikwadi, B. 2016. Parasitoid, Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae): its biology, morphometrics, host stage preference and use in biological control. Journal of Biological Control 30: 91-98.
Attia, A.R., Awadallah, K.T. and Noyes, J. 2017. First Record of Aenasius arizonensis (Hymenoptera: Encyrtidae) as a solitary, endoparasitoid of cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) infesting different host plants at Giza Region in Egypt. Egyptian Academic Journal of Biological Sciences 10: 127-134.
Badshah, H., Ullah, F., Calatayud, P.-A. and Ahmad, B. 2018. Influence of the host plant on the encyrtid Aenasius bambawalei, a parasitoid used to control the cotton mealybug, Phenacoccus solenopsis, in Pakistan. Pakistan journal of zoology 50: 207-216.
Badshah, H., Ullah, F., Calatayud, P.-A., Ullah, H. and Ahmad, B. 2017. Can toxicants used against cotton mealybug Phenacoccus solenopsis be compatible with an encyrtid parasitoid Aenasius bambawalei under laboratory conditions? Environmental Science and Pollution Research 24: 5857-5867.
Karmakar P. and P. S. Shera, P.S. 2017. Toxicity of insecticides to Aenasius arizonensis (Girault) (=Aenasius bambawalei Hayat), a solitary endoparasitoid of Phenacoccus solenopsis Tinsley on Bt cotton under semifield conditions. Journal of Biological Control 31: 5-9.
Pala, R. and Saini, R.K. 2010. Biological control solenopsis mealy bug Phenacoccus solenopsis Tinsley on cotton: a typical example of fortuitous biological control. Journal of Biological Control 24: 104-109.
Shera, P.S. and Karmakar, P. 2018.Effect of mating combinations on the host parasitisation and sex allocation in solitary endoparasitoid, Aenasius arizonensis (Hymenoptera: Encyrtidae). Biocontrol Science and Technology 28: 49-61.
Shera, P.S., Karmakar P., Sharma, S. and Sangha, K.S. 2017. Suitability of different mealybug species as hosts to solitary endoparasitoid, Aenasius arizonensis (Girault) (=Aenasius bambawalei Hayat). International Journal of Pest Management 63: 280-288.
Spodek, M., Ben-Dov, Y.,Mondaca, L.,Protasov, A., Erel,E. and Mendel, Z. 2018. The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) in Israel: pest status, host plants and natural enemies. Phytoparasitica 46: 45-55.
Tanwar, R. K., Jeyakumar, P. and Singh, A. 2011. Survey for cotton mealybug, Phenacoccus solenopsis (Tinsley), and its natural enemies. Journal of Environmental Biology 32: 381–384.
Zhou, A., Lu, Y., Zeng, L., Xu, Y. and Liang, G. 2017. Solenopsis invicta (Hymenoptera: Formicidae), defend Phenacoccus solenopsis (Hemiptera: Pseudococcidae) against its natural enemies. Environmental Entomology. 42: 247-252.
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