The Invasive Nearctic Pest Platynota stultana Walsingham (Lepidoptera: Tortricidae) Is Established in Southern Italy

TL;DR

A harmful moth from North America has become established in Southern Italy, raising concerns about its spread and impact on crops due to climate change.

Contribution

The first confirmation of Platynota stultana's establishment in Southern Italy through genetic analysis and population observations.

Findings

Platynota stultana is now established in Southern Italy, as evidenced by multiple sightings over two years.

Genetic analysis revealed three haplotypes, with two matching those from Florida, suggesting multiple introductions.

Global warming may facilitate the moth's expansion in the Mediterranean, posing a threat to agriculture.

Abstract

Platynota stultana is a Nearctic moth known to be a polyphagous pest of economic importance that targets many horticultural, fruit, and flower crops in North America. Its introduction into warm climate regions, through the trade of agricultural products, is feared. It is a quarantine pest worldwide. The Mediterranean Basin, with regions characterized by a climate close to that of its native range (South-Western USA and Mexico), is at risk of invasion. In this area, to date, the species is only established in Spain, where it is of limited economic interest. In Italy, P. stultana has been reported sporadically several times, but it is unknown whether these records are transient findings or the result of an establishment. In this study, we show that P. stultana has become established in Southern Italy. Through sequencing and phylogenetic analysis of the mitochondrial COI gene, we characterized the genetic diversity of the sampled populations and their geographical origins (predominantly Florida and California). Due to global warming, which is severely affecting the Mediterranean Basin, P. stultana could find better conditions under which to expand its range and become an economic pest. Our results indicate a need to implement an adequate monitoring plan in Southern Italy to allow timely planning of control measures.

Platynota stultana is a Nearctic moth of economic importance for many crops in North America. It is a quarantine pest in Europe, where Mediterranean regions, with warm climates similar to those of the moth’s native range, are at risk of invasion. To date, the species is established only in Spain. It has been reported sporadically in Italy, but it is unknown whether these were transient findings or the result of an establishment. In this study, the presence of P. stultana in the Campania region, Southern Italy, was recorded. Adults of both sexes were found in different locations and in two consecutive years, suggesting that the species is established. Sequencing the COI gene identified three haplotypes of P. stultana, suggesting possible multiple introductions. The two most numerous haplotypes were identical to haplotypes from Florida. Phylogenetic analysis showed that the P. stultana clade splits into two subclades. The Italian haplotypes are all grouped into the same subclade. Our data suggest that P. stultana is expanding its range of invasion into Southern Italy, where, due to global warming, it may find increasingly favorable conditions and become an economic pest. A monitoring plan is required to allow timely implementation of control measures.

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