Genomic tools will help facilitate the shift to greener crop protection

Langley, BC – A Genome BC research project will test the egg-laying capacity of predatory mites as a method of standardizing and improving biocontrol programs.

Two-spotted spider mites are a continuing plague to growers in BC and around the world, where they feed on and damage greenhouse vegetables and ornamental flowers and plants. But current biocontrol methods for controlling spider mites, though widely diverse, are not fully meeting the needs of growers.

Synthetic pesticides are losing popularity among ecologically conscious consumers and growers alike. Alternative methods rely on the use of predatory insects and mites – natural enemies of spider mites.

The predatory mite, P persimilis, (Pp) is the most frequently released natural enemy of spider mites used for the control of these pests on greenhouse and outdoor crops. Although they have been commercially produced for many years, the batch-to-batch quality of Pp populations, as defined by their egg-laying potential, remains inconsistent.

Brian Spencer is a Pp producer with Applied Bio-nomics, who has experienced this challenge first-hand. “Currently there is no rapid method of sorting out the reproductive potential of a given batch of Pp females, which measure less than a millimeter in size,” he says.

Spencer is part of an international group of Pp producers who, together with investment from Genome BC, have set out to develop a tool to enhance the quality of the mite populations and standardize their performance at the time of their release.

The research project, entitled Development of a Molecular-based Probe Test for Assessment of Fecundity of P persimilis Populations, is led by Dr Brian Ellis, professor and associate director of Michael Smith Labs at UBC, along with a team of multi-disciplinary co-investigators including Anna Luczynski (Qadra Consulting) and Dr Yves Thiberghien (UBC).

The goal of the research is to develop a simple molecular test to quickly measure the egg-laying potential of Pp populations.

The research uses proteomics and genomics tools to identify the biomarkers that can determine the reproductive quality of a given batch.

“We are looking for protein differences to help us distinguish between females that have exhausted their egg-laying capacity and ones that are still fully capable,” says Dr Ellis.

The first step of the research is to determine whether the protein differences actually exist and whether they can be identified.

“Ultimately, we would like to create a probe-test for mite fecundity (egg-laying capacity) that is similar to a human home pregnancy test,” he says.

This simple and rapid test has the potential to improve methods of mass production of P persimilis, increase the adoption of this biocontrol program around the world, as well as serve as an example for ways to improve efficiency of other biological control agents.

“We are very pleased to support this vital and innovative research,” says Dr Alan Winter, Genome BC’s president and CEO. “This project will contribute to moving current agricultural practices towards a greener model for the future.”