Translator Disclaimer
1 August 2006 Importance of Direct Spray and Spray Residue Contact for Infection of Trichoplusia ni Larvae by Field Applications of Beauveria bassiana
Author Affiliations +
Abstract

Commercial formulations and unformulated conidia of Beauveria bassiana strain GHA were applied to field-grown plants and artificially infested with Trichoplusia ni (Hübner) larvae to compare the relative insecticidal activity resulting from direct spray contact with insecticidal activity due to contact with dry spray residue. In general, applications to cabbage, Brassica oleracea L., resulted in nearly equal mortalities when comparing insects exposed to direct spray contact with those exposed by spray residue, suggesting a potential benefit by improving formulations to extend residual activity. For applications to beans, Phaseolus vulgaris L., direct spray contact provided significant insect mortality, but mortality due to residual contact was generally not different than the untreated control. In contrast to the differences observed for larvae exposed in the field, larvae exposed in laboratory bioassays to leaf disks collected from the same treated cabbage and bean plants (residual contact exposure) resulted in nearly identical mortalities. Field applications of Beauveria showed rapid loss of activity, expressed as a loss of conidia viability and loss of insecticidal activity during the first 8 h after application. Evidence of significant mortality by residual contact and the rapid loss of insecticidal activity with field exposure support additional research to improve formulations to extend the residual activity of fungal biopesticides.

Robert W. Behle "Importance of Direct Spray and Spray Residue Contact for Infection of Trichoplusia ni Larvae by Field Applications of Beauveria bassiana," Journal of Economic Entomology 99(4), 1120-1128, (1 August 2006). https://doi.org/10.1603/0022-0493-99.4.1120
Received: 21 December 2005; Accepted: 1 April 2006; Published: 1 August 2006
JOURNAL ARTICLE
9 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top