Journal article

Publication year: 1996

Pages: 619-626

Journal: Journal of Applied Entomology

Volume number: 120

Issue number: 10

ISSN: 0931-2048

DOI Link: https://doi.org/10.1111/j.1439-0418.1996.tb01661.x

Publisher: Wiley

Abstract: 
Studies were conducted on the bionomy of the Colorado Potato Beetle at one site in Hesse (FRG), 1994. Furthermore, at another site, a field trial with natural insecticides gave answers on the efficiency of the preparations, and on the evaluation-methods. A hatching-rate of 79.5% from laid eggs to L(1)-larvae was determined. Tests on the cannibalism of eggs showed that adults destroyed up to 31% ((x) over bar = 19%) of the eggmasses. A clear relation between beetle density and rare of cannibalism could not be found, however. A field-trial with a preparation of Bacillus thuringiensis var. tenebrionis (B.t.t.; 'Novodor') and a Azadirachtin-preparation ('NeemAzal-T') took place. Two different concentrations per preparation and one combination showed, that an effective pest-management with biological insecticides is possible. Due to the evaluation method, efficiency rates higher than 90% (Novodor 41/ha) and 88% (NeemAzal-T 1.21/ha) were measured. However, the analysis of plant-damages caused by the feeding of the beetles and larvae was also important to evaluate the efficiency of the preparations tested. A reduction to only 25% plant defoliation at mid-July proved to be possible by NeemAzal (1.21/ha), as well as by Novodor (41/ha). The untreated plots showed 80% plant-damage at that time. Defoliation rates at 21. July reached 93% in untreated plots, 32% with neem and 64% with B.t.t. To recognize possible long-term effects, surviving L(4)-larvae were collected and observed in the greenhouse concerning their ability to pupate. While all larvae treated with B.t.t. grew up to adults like untreated larvae, neem-treated larvae died in the prepupal stage.

Harvard Citation style: Schrod, J., Basedow, T. and Langenbruch, G. (1996) Studies on bionomy and biological control of the Colorado Potato Beetle (Leptinotarsa decemlineata Say, Col, Chrysomelidae) in Hesse (FRG)., Journal of Applied Entomology, 120(10), pp. 619-626. https://doi.org/10.1111/j.1439-0418.1996.tb01661.x

APA Citation style: Schrod, J., Basedow, T., & Langenbruch, G. (1996). Studies on bionomy and biological control of the Colorado Potato Beetle (Leptinotarsa decemlineata Say, Col, Chrysomelidae) in Hesse (FRG).. Journal of Applied Entomology. 120(10), 619-626. https://doi.org/10.1111/j.1439-0418.1996.tb01661.x