Japanese beetle feeding and survival on apple fruits

Abstract

Popillia japonica (Coleoptera: Scarabaeidae), Japanese beetle, is a polyphagous pest of many crops. In these crops, including apple, it acts primarily as a defoliator, causing economic damages. The objectives were to determine the ability of P. japonica to injury fruits of SweeTango variety apples and the suitability of apple fruits as a food source for this beetle. Popillia japonica was not able to injure the surface of intact fruits, which means that it is not a primary pest for apple fruits. The lifespan of the beetles when fed soybean leaves or apple with exposed endocarp was similar. Observations of the feces of the beetles suggest a potential physiological response due the change of food from soybean leaves to apple fruits. Therefore, we can conclude that the adults should not be considered as primary pests of apple fruits; however, they may act as secondary pests if the endocarp of the fruits is exposed by some other agent.

A nationwide pest risk analysis in the context of the ongoing Japanese beetle invasion in Continental Europe: The case of metropolitan France

“…The entry will likely occur through natural spread, since the beetle has high flight ability at the adult stage, or by hitchhiking behaviour, given the recent adult sightings in Basel (Switzerland, in 2021) and Baden-Württemberg (Germany, in 2021 and 2022) close to railway track or freight depot ( ), in the Valle d’Aosta region (Italy, in 2021) near a motorway service area, and in Sardinia (Italy, in 2021) near the main airport of the island ( 20 ). If no regulations were in place, the likelihood of entry would be increased by imports of plants for planting with adherent soil from infested countries, taking into account the probability that the aerial and subterranean stages are associated at the origin and transported, the diversity and volume of the transported goods (such as roses and fruit tree plants especially from Italy), the abilities of the beetles to survive without food ( 21 , 22 ) during transport, as well as their capacity of transfer to host plants cultivated in France.…”