hrvatski

MOGU LI TRČCI (Coleoptera: Carabidae) KONTROLIRATI INVAZIVNOG LUZITANSKOG PRPOLJA Arion lusitanicus (Gastropoda: Pulmonata: Arionidae)?

The Iberian slug, Arion lusitanicus auct. non-Mabille (also known as Arion vulgaris Moquin-Tandon 1855), apparent to be native to south-west Europe, has been classified as invasive species to the North and Central Europe. The first record of this pest species in Central Europe was reported in 1950s and its occurrence in Croatia has been dated from 1996. In Central Europe, Iberian slug has been the major pest slug species, making damages on wild and cultivated plants. In Croatia the species has been reported from strawberry and vegetable fields, as well as in many small gardens, but its economic impact for the country has not yet been estimated. Although some recent papers questioned the invasiveness and the origin of Iberian slug, still their high abundance in the agricultural fields causes the extensive use of molluscicide. Carabid beetles are important predators in soil ecosystems regulating prey abundance. They are common in forest as well as in agricultural fields where they can be very important as natural enemies to many pest and invasive species. Therefore, I analysed the diet of predatory carabid beetles in the field, as potential biocontrol agents in reducing the populations of Iberian slug, and thus the use of pesticides. As most of the carabids forage by night, the observation of predation in the field is very hard. Furthermore, microscopic analysis of carabid gut proved ineffective for identifying soft-bodied prey, especially for eggs and juvenile slugs that many carabids prefer more than adults, as adults have thicker skin and secretes more mucus. Therefore, I utilised MGCA (molecular gut content analyses) and screened the carabid community for Arion species. The use of molecular filed analyses proved as very effective and yielded a list of species positive for Arion slugs in their diet. Five out of 14 carabid species were positive for Arion. Only 10 % of overall beetles were positive for Arion, and 23% were positive for Limax slug species. As Limax cinereoniger were more abundant in the field than Arion species, prey filed density may be the reason for the prey ratio detected in the gut of the predators. Native carabid fauna can be valuable in biological control of slug pests. Further studies should be provided in Arion dominant environment, as well as on carabid sustainability in the field and effectiveness as pest predators in order to enhance management approaches.

biološka kontrola; predatorstvo; fauna tla; Mollusca; Coleoptera; Carabidae

nije evidentirano

engleski

CAN PREDATORY CARABID BEETLES (Coleoptera: Carabidae) CONTROL INVASIVE IBERIAN SLUG Arion lusitanicus (Gastropoda: Pulmonata: Arionidae)?

The Iberian slug, Arion lusitanicus auct. non-Mabille (also known as Arion vulgaris Moquin-Tandon 1855), apparent to be native to south-west Europe, has been classified as invasive species to the North and Central Europe. The first record of this pest species in Central Europe was reported in 1950s and its occurrence in Croatia has been dated from 1996. In Central Europe, Iberian slug has been the major pest slug species, making damages on wild and cultivated plants. In Croatia the species has been reported from strawberry and vegetable fields, as well as in many small gardens, but its economic impact for the country has not yet been estimated. Although some recent papers questioned the invasiveness and the origin of Iberian slug, still their high abundance in the agricultural fields causes the extensive use of molluscicide. Carabid beetles are important predators in soil ecosystems regulating prey abundance. They are common in forest as well as in agricultural fields where they can be very important as natural enemies to many pest and invasive species. Therefore, I analysed the diet of predatory carabid beetles in the field, as potential biocontrol agents in reducing the populations of Iberian slug, and thus the use of pesticides. As most of the carabids forage by night, the observation of predation in the field is very hard. Furthermore, microscopic analysis of carabid gut proved ineffective for identifying soft-bodied prey, especially for eggs and juvenile slugs that many carabids prefer more than adults, as adults have thicker skin and secretes more mucus. Therefore, I utilised MGCA (molecular gut content analyses) and screened the carabid community for Arion species. The use of molecular filed analyses proved as very effective and yielded a list of species positive for Arion slugs in their diet. Five out of 14 carabid species were positive for Arion. Only 10 % of overall beetles were positive for Arion, and 23% were positive for Limax slug species. As Limax cinereoniger were more abundant in the field than Arion species, prey filed density may be the reason for the prey ratio detected in the gut of the predators. Native carabid fauna can be valuable in biological control of slug pests. Further studies should be provided in Arion dominant environment, as well as on carabid sustainability in the field and effectiveness as pest predators in order to enhance management approaches.

biocontrol; predation; soil fauna; Mollusca; Coleoptera; Carabidae

nije evidentirano