Pest categorisation of Oligonychus perseae

Abstract

The EFSA Panel on Plant Health performed a pest categorisation of Oligonychus perseae (Acari: Prostigmata: Tetranychidae), the persea mite, for the EU. O. perseae is a tropical species that originated in Mesoamerica and has now spread and established in California, Florida, Hawaii, Morocco, southern Europe and Israel. Within the EU, it is established in Italy, Portugal and Spain. O . perseae is not listed in Commission Implementing Regulation (EU) 2019/2072. It is polyphagous, feeding on plants in 20 genera in 17 families. It is most frequently reported on avocado ( Persea americana ), where it is considered a key pest. No evidence was found indicating damage to other crops. O. perseae live on leaves and do not attack the fruit. Populations usually grow exponentially at the beginning of summer and decline at the end of this season. High population densities can cause severe defoliation, resulting in downgrading of fruit through sunburn. However, this type of damage is common only if trees additionally suffer from water stress. The lack of additional avocado pests in the EU, which facilitates the production of organic avocados, is jeopardised by the occurrence of this mite, as it may require pesticide applications. This is why O. perseae is considered an important pest of avocados in Spain, where more than 80% of EU avocado production occurs. Natural dispersal is restricted to neighbouring trees. However, human‐assisted movement can result in long‐distance spread. Plants for planting provide potential pathways for further entry and spread, including O. perseae ‐free EU MS where avocados are grown (i.e. Cyprus, France, Greece). Climatic conditions and availability of host plants in southern EU countries are conducive for establishment. Phytosanitary measures are available to reduce the likelihood of further entry and spread. O. perseae satisfies with no key uncertainties the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.

Oligonychus perseae (Tetranychidae) Invasion in the Canary Islands: History, Management and Current Situation

“…Globally, O. perseae has been recorded on approximately 20 different hosts across 17 botanical families [31]. Based on the criteria outlined in Regulation (EU) 2016/2031, the EFSA (European Food Safety Authority) has concluded that O. perseae fulfils all the requirements to be considered a potential Union quarantine pest [32].…”

“…In the initial stages following the introduction of O. perseae in the Canary Islands, farmers resorted to applying acaricide products on their avocados without considering the actual mite population present. These applications were either done prematurely, with insufficient mite presence on the leaves, or delayed until the leaves exhibited significant damage [32]. This situation highlighted the importance of understanding the population dynamics of the pest, as well as determining the economic injury level (EIL) as represented by the percentage of maximum leaf damage (PLAD).…”