''Oobius agrili'' is a parasitic non-stinging wasp of family Encyrtidae which is native to

North Asia North Asia or Northern Asia, also referred to as Siberia, is the northern region of Asia, which is defined in geographical terms and is coextensive with the Asian part of Russia, and consists of three Russian regions east of the Ural Mountai ...

. It is a parasitoid of the

emerald ash borer The emerald ash borer (''Agrilus planipennis''), also known by the acronym EAB, is a green buprestid or jewel beetle native to north-eastern Asia that feeds on ash species. Females lay eggs in bark crevices on ash trees, and larvae feed underne ...

(''

Agrilus planipennis The emerald ash borer (''Agrilus planipennis''), also known by the acronym EAB, is a green buprestid or jewel beetle native to north-eastern Asia that feeds on ash species. Females lay eggs in bark crevices on ash trees, and larvae feed undern ...

'' Fairmaire, family

Buprestidae Buprestidae is a family of beetles known as jewel beetles or metallic wood-boring beetles because of their glossy iridescent colors. Larvae of this family are known as flatheaded borers. The family is among the largest of the beetles, with some ...

), an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...

which has destroyed tens of millions of ash trees in its introduced range in North America. As part of the campaign against the emerald ash borer (EAB), American scientists in conjunction with the

Chinese Academy of Forestry Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of v ...

searched since 2003 for its natural enemies in the wild leading to the discovery of several parasitoid wasps, including ''Oobius agrili,'' which is a solitary egg parasitoid of EAB found on ash trees in

Jilin Jilin (; alternately romanized as Kirin or Chilin) is one of the three provinces of Northeast China. Its capital and largest city is Changchun. Jilin borders North Korea ( Rasŏn, North Hamgyong, Ryanggang and Chagang) and Russia (P ...

province in 2004; it has been recorded to kill up to 60 percent of EAB eggs. Field studies were carried out in 2005 which revealed that ''Oobius agrili'' completes at least two generations per year. The peak period for parasitism was during July and August where egg parasitism rates were 56.3 percent and 61.5 percent, respectively. ''O. agrili'' is parthenogenic and has a sex ratio of 14.5:1 (female:male). ''O. agrili'' achieves synchrony with its host life cycle—part of the ''O. agrili'' larvae population in eggs of EAB undergoes diapause within the eggs during winter and emerges the following summer. The USDA carried out paired choice assays with eggs of six different native Agrilus species, two cerambycid beetles, and four lepidopterans. ''O. agrili'' ignored eggs of all other species except of three of the Agrilus species of egg size in the same range as that of EAB. ''O. agrili'' strongly preferred to oviposit in EAB eggs laid on ash than in eggs of other Agrilus species on their respective host plants. The selectivity shown by ''O. agrili'' has led to its being included in the

biological control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically als ...

program for controlled releases in selected sites for further research.

References

{{Taxonbar, from=Q7095229 Encyrtinae Biological pest control wasps Insects described in 2005