The Asian citrus psylla is already in the Mediterranean: threat to Spanish citrus fruit growing

By hlb-editor | May 25, 2022 | News | 0 comments

Article by Alberto Fereres, project partner, in Interempresas (in spanish) with the main results of the proyect at the moment.

With the detection of the Asian psylla, Diaphorina citri, in Israel in July 2021 and its subsequent establishment in one of the most important citrus production regions (Emek Hefer), a great threat to the entire citriculture of the Mediterranean basin has arisen.

This insect is the main vector of the most aggressive variant of the bacterium that causes the Huanglongbing (HLB) or Yellow Dragon disease. This disease could cause millions of dollars in losses in Spain such as those it has already caused in Florida citriculture in the past few years, where production has been reduced by 74% since the entry of HLB in 2005. It is therefore a high priority to improve early detection systems for the disease and its vectors, but also to tighten border inspection measures for plant material coming from countries where the disease is already established.

The confirmation by the Israeli authorities of the detection of Asian citrus psylla, Diaphorina citri in Israel on 26 January 2022 has put the entire Mediterranean citrus sector under pressure. For the time being, the focus of this detection is concentrated on about 25 hectares north of Tel Aviv, in the region of Emek Hefer, very close to the city of Netanya, and this is the first time that the presence of this insect has been reported in the Mediterranean basin.

The insect Diaphorina citri is a psylla, a hemipteran insect about 4 mm long and producing very characteristic honeydew. This insect has been widespread for many years in the Americas, in Asia and more recently in some African countries. D. citri is the main vector of the bacterium causing the most serious citrus disease: Huanglongbing (HLB).

This disease, also known as Yellow Dragon Disease (also known as HLB), has had devastating consequences on citrus growing in countries such as the United States of America. The bacterium causing HLB belongs to the genus Candidatus Liberibacter spp. and has 3 variants or species, the so-called Ca. L. asiaticus (CLas), Ca. L. africanus (CLaf), and Ca. L. americanus (CLam). The most aggressive variant causing the most devastating damage in Florida, Cuba and Brazil is the Asian or CLas variant, which is precisely the one that transmits the Asian citrus psylla, D. citri. Therefore, the arrival of the D. citri vector in a new region, as has recently occurred in Israel, poses a very serious threat due to the risk that the HLB disease could spread rapidly if infected plants were introduced.

Read the full article in spanish following this link

Leave a Reply

Your email address will not be published. Required fields are marked *

Post comment