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The current study was carried out at the Experimental Farm of Sakha Agricultural Research Station during three cultivations in 2018/19 and 2019/20 seasons. The present study includes a survey of the predatory formicid species associated with the beet moth, Scrobipalpa ocellatella Boyd. larvae in sugar beet fields. The obtained results showed larvae numbers of S. ocellatella increased towards the end of the season and formicid populations were synchronous with that of S. ocellatella in the three cultivations. The simple correlation coefficient values between S. ocellatella larvae population and the predatory formicid populations were very highly positive significant in the two seasons. Five predatory formicid species were recorded belonging to the family Formicidae under the order Hymenoptera, three of them were: Tetramorium depressiceps Menozzi, Tetramorium brevicoryne Brondroit and Camponotus thoracicus (Fah.) recorded by high percentages. While the other two formicid species: Tapinoma simrothi Krausse and Solenopsis latro L. recorded low percentages. As for predation and food preference, the predatory formicid species prefer S. ocellatella larvae to eggs and pupae throughout the three sugar beet cultivations during the two seasons of study. These results proved that formicid species are important predators to S. ocellatella larvae. There for the current investigation aimed to add some contributions to the knowledge of the predatory formicid species as natural biological control agents in Egyptian sugar beet fields.

Article History

The current investigation was carried out during 2012/13 and 2013/14 sugar beet seasons at the Experimental Farm of Sakha Agricultural Research Station and laboratory of Plant Protection Department, Faculty of Agriculture, Tanta University for identifying the arthropods (insect pests and acari) trapped in spider webs. Most of trapped arthropods pests were collembolan (48.08%), followed by aphids (Aphis gossypii (Glover) and others) (25.64%). Moderate number of cicadellids (12.82%), Thrips tabaci Lind. (4.81%), Spodoptera littoralis (Boisd.) larvae (3.21%), Spodoptera exigua (Hubn.) larvae (2.88%) and Tetranychus sp. (2.56%). Also, eight spider species, belonging to five families were surveyed. The highest family was Araneidae which contained three species, Araneus sp., Argiope trifasciata Forscall and Singa sp. followed by Linyphiidae was represented by two species (Bathyphantes sp. and Erigone sp.). Each of Amaurobiidae (Amaurobius sp.), Dictynidae (Dictyna sp.) and Theridiidae (Theridion sp.) had one species only. Finally, these results show the importance of spider webs in capturing sugar beet pests, consequently, play a major role in controlling pests without use of any pesticides.

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