Evaluation of XenTari for the management of diamondback moth in canola

Project Code BPR12-030

Project Leads

Gary Coukell  Integrated Crop Management Service (ICMS)

Objective

To develop efficacy and crop tolerance data in support of a regulatory submission for XenTari (Bacillus thuringiensis ssp. aizawai) for the management of diamondback moth in canola

Summary of Results

Background

Canola is grown primarily in the prairie provinces of Canada, with some acreage in British Columbia, Ontario and Quebec. Saskatchewan accounts for 44% of the Canadian production, Alberta 30% and Manitoba 25%. Crop acreage has increased due to the success of international marketing. Diamondback moth (DBM) is a potentially very destructive pest to canola and an outbreak may result in significant yield losses of up to 80%. During the 2011 Biopesticides Priority Setting workshop XenTari WG Biological Insecticide was selected for the management of DBM in canola.

XenTari WG Biological Insecticide is a selective insecticide for use against larvae of lepidopterous insects. XenTari Biological Insecticide has efficacy against armyworm and diamondback moth larvae. The active ingredient in XenTari is composed of protein crystals and viable endospores from a pure, potent strain of Bacillus thuringiensis ssp. aizawai.

Approaches

Two field trials were conducted in Abbotsford and Okanagan Falls, British Columbia, in 2012. Trials were set up as a complete randomized block design with four replicates. XenTari Biological Insecticide was applied at the rates of 500 or 1000 grams of product per hectare in a water volume of 100 Litres per hectare when canola plants were at the early flowering stage. One application was made. The commercial standard, Decis (deltamethrin), was tested for comparison. Efficacy against DBM was evaluated at 7 day intervals after the application of insecticides by counting the number of larvae and pupae present and assessing feeding damage on the leaves of 10 or 20 canola plants per plot.

Crop tolerance to XenTari Biological Insecticide was assessed 4-8 times by visually rating the treated plants in the plots at 6-7 day intervals after the product application using the following scale: 0 equals no injury, 100 equals dead. Data were subjected to statistical analysis.

Results

Results of field trials showed that when applied at the rates of 500 and 1000 grams per hectare under medium to high pest pressure, XenTari WG Biological Insecticide provided control of DBM on canola. No significant differences were observed between the two application rates. The application of XenTari Biological Insecticide resulted in 57- 63% reduction of larval and pupal counts. Generally, the commercial standard, Decis, performed better than XenTari WG Biological Insecticide. There were no phytotoxicity effects from any of the treatments. 

Date modified: