Evaluation of plant pathogens and their removal from greenhouse irrigation water by cost effective bioremediation and filter technologies ABP 0031

A comprehensive survey of plant pathogen populations (measured by DNA Multiscans) in irrigation water leachate and/or runoff from the range of Ontario flower and vegetable greenhouses and container nurseries was conducted to help assess the level of risk involved in operations switching to recirculating systems. The ability of several bioremediation technologies to remove plant pathogens from recycled irrigation water (e.g. constructed wetlands, woodchip biofilters) was evaluated as well as the effectiveness of current plant pathogen disinfection systems.

Greenhouse Process Water Quality and Quantity Characterization Analysis

A biweekly sampling program to determine the water quality of greenhouse process water (feed, leach and collection pond water) was conducted at 7 vegetable and 8 flower greenhouse operations. As well, a water use and management paper survey across a wider range of operations was conducted to determine the quantity of water being used for irrigation and the degree to which unused irrigation water (leach) is being captured and reused, and issues surrounding water use/reuse management. A total of 9 vegetable growers completed surveys (3 tomato, 2 cucumber, 3 pepper, and 1 tomato and pepper operations), and 27 flower operators were surveyed, with approximately even representation from the five major production categories (cut recirculating, cut open, potted plant recirculating, potted plant open, and cut flowers grown in soil).

Best Management Practices for the Ontario Greenhouse and Container Nursery Industry to Protect Surface and Sub-surface Water Quality TOGA-OMAFRA Great Lakes Project 07-038)

The project objectives were to demonstrate the principles of collection, treatment, and reuse of irrigation runoff water in the greenhouse horticulture industry and develop and draft a. Existing treatment systems were monitored at three sites and new systems were installed and monitored at the seven sites. Irrigation water runoff and water at interim stages of each treatment system were monitored to determine their effectiveness. A Greenhouse and Container Nursery Water and Nutrient Management BMP document was drafted which formed the basis of the three individual OMAFRA BMP and self-assessment guides for greenhouse vegetable, container nursery, and greenhouse floriculture production.