Evaluation of Problad Plus for the management of grey mold in greenhouse peppers

Project Code: BPR14-050

Project Lead

Janice Elmhirst Elmhirst Diagnostics and Research, British Columbia, Canada
Diane Logeot Ag-Quest, Incorporated, Manitoba, Canada

Objective

To develop efficacy and crop tolerance data in support of a regulatory submission for the biopesticide Problad PlusTM for the management of grey mould (Botrytis cinerea) in greenhouse peppers

Summary of Results

Background

Grey mould (Botrytis cinerea) is a serious problem in most places where greenhouse peppers are grown in Canada. During the annual Biopesticide Priority Setting Workshop in March 2013, Botrytis grey mould in greenhouse peppers was identified as a priority issue by Canadian growers, with Problad PlusTM selected as a potential solution for the management of this disease. Problad PlusTM is a broad spectrum, preventive biopesticide containing 20% of Banda de Lupinus albus doce (BLAD), a naturally occurring seed storage protein in sweet lupines. Problad PlusTM is registered by CEV, S.A. (Consumo em Verde, Portugal) in the United States under the trade name of FractureTM on grapes, almonds, strawberries, tomatoes, and stone fruits for the control of diseases including Botrytis grey mould.

Pesticide Risk Reduction is working with industry to facilitate the submission of an User Requested Minor Use Label Expansion (URMULE) to include this use in the Canadian registration of the product. The efficacy trials were conducted in British Colombia (B.C.) and Manitoba in 2014 to develop efficacy and tolerance data.

Approaches

Problad PlusTM was evaluated in comparison to the commercial standards Fontelis (penthiopyrad) and Cease Biofungicide for the control of Botrytis grey mould in greenhouse pepper in B.C. and Manitoba under low to moderate disease pressures derived by inoculation. There were 4 treatments including untreated check (water only), Problad PlusTM at 1.86 litres per hectare (L/ha) and 3.72 L/ha, and Fontelis at 1.75 L/ha or Cease Biofungicide at 9.4 L/ha as the commercial standard. Each treatment had 4 replicates and was applied 6 times at an approximately weekly interval in the greenhouse. The diseased leaf incidence, diseased leaf severity, bloom grey mould, petiole lesions, stem cankers, and fruit rot were assessed for evaluation of efficacy.

Results

During the trial in B.C., the higher rate of Problad PlusTM significantly reduced the mean percentage of diseased leaves by 40% and the mean number of botrytis leaf spots per plant by 64% compared to the untreated check. The lower rate of Problad PlusTM was not statistically different from the untreated check for the control of leaf disease on most treatment dates, but was more effective on petiole and stem lesions with 82% reduction in petiole lesions and 100% reduction in stem cankers. The performance of the lower rate was similar to effectiveness provided by the commercial standard Fontelis for the control of petiole lesions and stem cankers. The higher rate of Problad PlusTM was less effective on petiole and stem cankers and none of the treatments reduced botrytis grey mould on blooms, botrytis fruit rot, or botrytis ghost spot on fruit. There was no significant difference in marketable or total yield among all treatments.

During the trial in Manitoba, the two rates of Problad PlusTM did not provide significant efficacy compared with the untreated control, but numerically reduced disease severity by up to 30% and disease incidence of Botrytis grey mould by up to 50%. The performance of the two rates was similar to the commercial standard Cease Biofungicide.

No phytotoxicity was observed within either of the two trials.

The data from this project will be used to support a submission to Pest Management Regulatory Agency to add management of Botrytis grey mould in greenhouse peppers to the Canadian label for Problad PlusTM.