Biological Control: A Sustainable Strategy Against Invasive Citrus Snail

Abstract

Snails are polyphagous pests that cause damage to several crops worldwide. They feed on the leaves and fruits of this crop and transmit certain fungal diseases. The present study aims to elucidate the protective role of the biological control approach against invasive snails. Citriculture in Morocco, particularly in the Gharb region, faces several phytosanitary problems, including snails. Three species, Theba pisana, Helix aspersa, and Eobonia vermiculata, have been associated with citrus orchards in this region. The current practice to combat these pests predominantly rely on molluscicidal products containing active ingredients such as metaldehyde, abamectin, indoxacarb, chlorfluazuron, and spiromesifen. However, due to the negative effects of chemical control on the environment and non-target species, these products are not a sustainable primary strategy for managing snail invasions. Effective management of invasive snails requires an integrated pest management (IPM) approach, such as i) cultural methods like manual collection from the trunk and branches, ii) Physical control using barrier traps that can be optionally combined with mineral oil, or attractants, and iii) Biological control can be achieved through the use of parasitic nematodes or plant extracts. Promising biological agents such as essential oil extracted from Citrus limon zest, aqueous extract of thyme, as well as lupin extract nanoparticles coated with copper sulfate and starch, which have demonstrated 100% mortality and inhibited egg laying.

Keywords: Invasive Snails, Theba pisana, Eobonia vermiculata, Citrus orchards, Biological controls, Sustainable