The Role of Parasitoids in Limiting the Harmfulness of Leafrollers in Apple Orchards

Abstract

Abstract:The aim of the studies was to determine significance of parasitoids as biocontrol agents against teafrollers in apple orchards. The studies were performed in different parts of Poland in 1994-2001. An average parasitization level of caterpillars amounted to ca.8.6%, and it varied broadly up to individual orchards (from 2.4 to 32.4%). A natural parasitization level was strictly related to the intensity of orchards' protection against pests. Higher parasitization was observed in case of less protected orchards, and in those ones with a great number of leafrollers.The greatest share in parasitizing leafroller caterpillars was stated for hymenopterans belonging to two families: Ichneumonidae The results of conducted research also revealed preferences of particular parasitoids to parasitize some leafroller species.A. rufidens had the greatest share in parasitizing caterpillars of Pandemis heparana. Among hymenopterani parasitoids of Archips rosanus, the one most numerously occurring was C. mutabilis, also considered as the main parasitoid of Acleris rhombana. In parasitizing the leafroller Adoxophyes orana the greatest share fell to M. ictericus while in case of Spilonota ocellana -the most frequent parasitoid was A. quadridentata.Tachinid flies were found to be of a minor importance in parasitization of leafroller caterpillars. They were only raised from four leafroller species, and their largest share fell in parasitization of A. rosanus.Parasitation of A. rosanus eggs by Trichogramma sp. varied broadly depending on individual orchards and growing seasons, and ranged 0.8 to 33.9%.

Mating disruption of Spilonota ocellana and other apple orchard tortricids using a multispecies reservoir dispenser

“…However, as the effect of pheromones on population control occurs over a certain number of generations, a further reduction in injury and thus in insecticide use is anticipated in a time range of 3–5 years. As a consequence, an enhancement of leafroller biological control by natural antagonists is also expected, which in turn may lead to increased orchard resilience …”

“…As a consequence, an enhancement of leafroller biological control by natural antagonists is also expected, which in turn may lead to increased orchard resilience. 23,24 Judd and Gardiner 25 found that inhibition of the mating of C. pomonella females in fields treated with a multispecies dispenser for C. pomonella/leafrollers did not differ from that of the corresponding dispenser for C. pomonella alone. In the present field conditions, the inhibition of trap catches and communication disruption in cages was incomplete for this species.…”

Integrated management of tortricid pests of tree fruit

“…The use of more selective insecticides has also expanded the importance of natural enemies of leaf rollers (Vakenti et al 2001;Cossentine et al 2004;Pluciennik and Olszak 2010;Monteiro et al 2012). In some regions the combined activity of these guilds has likely contributed to significant declines in their pest status (Blommers 1994;Lo et al 2018).…”

Controlling the abundance of the rose tortrix moth [Archips rosana (L.)] by parasitoids in apple orchards in Wielkopolska, Poland

“…The rose tortrix moth [Archips rosana (Linnaeus)] belongs to the leafroller family of moths (Lepidoptera: Tortricidae), which are found in large numbers ever year in Poland's apple orchards and have to be controlled chemically (Płuciennik & Olszak 2010). For many years, the rose tortrix moth has been one of the most dominant species among the phytophages found in western and south-eastern Poland (Płuciennik & Tworkowska 2004;Kot & Jaśkiewicz 2007;Piekarska-Boniecka et al 2008).…”

“…Entomophagous parasitoids are one of the biotic factors which control the abundance of the rose tortrix moth. They can attack the eggs, the larvae and the pupae of the moth (Miczulski & Koślińska 1976;Dronka 1981;Mey 1987;Balazs 1997;Kot 2007;Płuciennik & Olszak 2010;Polat & Tozlu 2010;Piekarska-Boniecka & Trzciński 2013;Aydoğdu 2014) and limit the moth population. https://doi.org/10.17221/9/2019-PPS s The aim of the study was to define the degree of parasitisation of the rose tortrix moth in its pupae stage, and determine the effectiveness of the parasitoid species of the family Ichneumonidae (Hymenoptera: Apocrita) in reducing its numbers.…”