Project Code: BPR12-070
Project Lead
Janice Elmhirst - Elmhirst Diagnostics and Research
Robert Doell - Ag-Quest, Incorporated
Michael Brownbridge - Vineland Research and Innovation Centre
Objective
To develop efficacy and crop tolerance data in support of a regulatory submission for SuffOil-X (mineral oil) for the management of thrips in greenhouse ornamentals
Summary of Results
Background
Thrips can cause major damage to many ornamental plants grown in greenhouses. Thrips species commonly found in Canada include Western flower thrips (WFT) (Frankliniella occidentalis), Eastern flower thrip (Frankliniella tritici), European flower thrips (F. intosa), greenhouse thrips (Heliothrips haemorrhoidalis), banded greenhouse thrips (Hercinothrips feoralis) and onion thrips (Thrips tabaci). Two new recent thrips identifications in British Columbia are Echinothrops americanus and Frankliniella intonsa. Thrips simplex are also a pest of gladiolus corms and damage their leaves. However, WFT are the most predominant species found across Canada and are known to be the most difficult of thrips to control. Thrips are currently managed through a variety of conventional insecticides, as well as biological controls in integrated pest management systems, and there is a need for additional tools. At the annual Biopesticides Priority Setting workshop in March 2011, SuffOil-X (mineral oil) was selected as the priority biopesticide solution for the management of thrips in ornamental plants grown in greenhouses.
Approaches
Three efficacy trials were conducted on chrysanthemums in British Columbia, Manitoba and Ontario during 2012. The trials were laid out in a randomized complete block (RCB) design, with 4 replicates of each treatment and 4 plants in each plot. Thrips were introduced to the chrysanthemums once or twice depending on the trial location. Three or four applications were carried out, with assessments made prior to each application, at 3 days after each application and at 7 and 14 days after the last application of SuffOil-X. Assessments were made by hand-tapping/brushing each plant 20 times onto a white paper sheet, and counting the number of adult and nymphs of each species. A commercial standard, Success 480 EC was also tested for comparison.
After thrips were counted, they were returned to their respective plant. Damage severity (thrips feeding scars) was assessed on 5 blooms and 5 leaves per plant at each assessment. Percent damage was assessed by two methods: (i) a direct estimate of area damaged on a scale of 0 to 100 percent (%) and (ii) on a scale of 0 to 5, where 0 equals 0 to 1%, 1 equals 2 to 5%, 2 equals 6 to 10%, 3 equals 11 to 20%, 4 equals 21 to 30%, 5 equals more than 30%. Crop tolerance was assessed on a scale of 0 to 100%.
Results
Results of this project showed that SuffOil-X applied at the rates of 10 and 20 millilitres of product per litre on chrysanthemums provided reduction of thrips populations (nymphs and adults of F. occidentalis and T. tabaci). Results varied across trial locations, with the level of control ranging from 13 to 70% compared to the water check. Results also showed that SuffOil-X performed as well as the commercial standard, Success 480 EC within these trials.
The data generated in this project conducted on chrysanthemum is sufficient to support the use of SuffOil-X in management of thrips in greenhouse raised chrysanthemum.
Pesticide Risk Reduction is working through its regulatory support team with the registrant toward the first time registration of this promising product in Canada.