Category Archives: Cluster 1

Dynamic greenhouse climate control to conserve energy and improve crop quality

Xiuming Hao, AAFC, Youbin Zheng, University of Guelph, Mike Dixon, University of Guelph

Conserving energy is a top priority for flower greenhouse operators. With this objective in mind, Dr. Xiuming Hao with Agriculture and Agri-Food Canada developed and assessed greenhouse heating and climate control strategies that would conserve energy without sacrificing timely production and maximum plant quality. The resulting Temperature Integration Strategy incorporates early morning and pre-morning temperature reductions producing a high quality, compact poinsettia plant that maintained leaf area, bract area and biomass while saving energy. The study also identified that higher root zone heating temperatures could be used with the new Temperature Integration Strategy for additional energy savings but irrigation management may need to be adjusted.

Further reading:
Response of poinsettias to dynamic temperature integration with pre-morning and early morning temperature drop and root zone heating.

Winter greenhouse heat consumption reduction

Damien de Halleux, Laval University; André Gosselin, Laval University; Xiuming Hao, AAFC Harrow

Damien de Halleux and his team at the Université Laval have developed a successful method of reducing energy costs in the production of potted plants such as poinsettia, hydrangea and petunia. Researchers have found that significant energy reductions of up to 20% can be achieved by a combination of reduced night time temperature, morning CO2 injections and ventilation control. The specific combination of these climatic adjustments enables average temperatures to be maintained at the optimal level and produces more vigorous plants that are ready for holiday delivery dates.

Optimization of management practices for biological control of thrips and other important pests of ornamental crops

Les Shipp, AAFC Harrow; Jacques Brodeur, University of Montreal; Cynthia Scott-Dupree, University of Guelph; Rose Buitenhuis, Vineland Research and Innovation Centre; Graeme Murphy, OMAFRA; Phyllis Weintraub, Agricultural Research Organization, Israel

Management of arthropod pests continue to be a serious challenge for greenhouse operators. Conventional controls are failing and few options remain to combat pest problems especially in the floriculture sector. Dr. Les Shipp with Agriculture and Agri-Food Canada has taken a targeted approach to assessing natural enemies by using pollen as a supplemental food source to boost the populations of predatory mites. Results have clearly demonstrated that cherry pollen, a readily available commercial product, is the most suitable supplementary food with predatory mites. Through this research, a set of cost-effective best management practices have been developed for the seasonal use of the predatory mites Neoseiulus cucumeris and Amblyseius swirskii for pest management of western flower thrips in greenhouse ornamental crops.

Biocontrol strategy for the control of aphids on greenhouse ornamentals

David Gillespie, AAFC Agassi; Jenny Cory, Simon Fraser University; Bernie Roitberg, Simon Fraser University

Dr. Dave Gillespie with Agriculture and AgriFood Canada has developed a strategy to use Botanigard in combination with natural enemies for control of aphids in greenhouse floriculture. This research has enhanced the general understanding of how parasitoids used for biological control of aphids in ornamental systems interact with Botanigard. It has also identified some critical knowledge gaps and opportunities for future technology development. A set of specific recommendations for growers to enhance aphid control in the greenhouse has been developed.

Biocontrol agents for turf pests

Michael Brownbridge, Vineland Research and Innovation Centre; Deborah Henderson, Kwantlen Polytechnic University; Pam Charbonneau, OMAFRA

To assess biocontrol agents for turf, Dr. Michael Brownbridge with Vineland Research and Innovation Centre, has led a study on five fungal entomopathogens, two nematode species, and neem seed cake applied alone and in combination to control European Chafer and Chinch Bug. Trials conducted in Ontario and British Columbia demonstrated neem seed cake as providing the best control of chafer larva although neem cake is not presently registered in Canada for insecticidal use. Soil studies of highly managed turf have indicated that there may be no natural fungal controls present that could suppress chafer infestations. A potential upside is that management of chafer in turf by adding beneficial strains of the fungus Metarhizium may be improved. Studies also demonstrated successful control of chinch bugs with nematodes and an experimental essential oil product.

Alternative weed control methods and bioherbicides in turf and nursery production

François Tardif, University of Guelph; Katerina Jordan, University of Guelph; Eric Lyons, University of Guelph; Rene Van Acker, University of Guelph; Michael Brownbridge, Vineland Research and Innovation Centre; Karen Bailey, AAFC, Saskatoon.

Landscapers know that weed control in turfgrass without the use of synthetic herbicides can be difficult. Dr. Francois Tardif with the University of Guelph has conducted field trials on a number of alternative weed control products and found that there is significant variation between the claims of manufacturers and actual product performance. While a few products provide control comparable to that of synthetic herbicides, most do not provide a level of control that would be acceptable for the majority of users. Over seeding with some grass species can lead to increased turf cover and is proving to be a favourable option in light of increasing restrictions on pesticide use. This research has delivered a set of clear recommendations for saving money and increasing the efficiency of controlling weeds in turf without conventional herbicides.

Water treatment technologies

Youbin Zheng, University of Guelph; Mike Dixon, University of Guelph; Xiuling Tian, University of Guelph; Mary Jane Clark, University of Guelph; Linping Wang, University of Guelph; Katherine Vinson, University of Guelph

A comprehensive list of water treatment technologies with specific and useful information is now available to industry. Dr. Youbin Zheng with Vineland Research and Innovation Centre and the University of Guelph completed a literature review and conducted interviews with growers and water treatment companies to assemble information on available technologies. An interactive website will provide growers with an on-line decision process for choosing appropriate technology for their own operation.

Further reading: Water Treatment Information System

Pathogen suppression in substrates

Youbin Zheng, University of Guelph; Mike Dixon, University of Guelph; Xiuling Tian, University of Guelph; Mary Jane Clark, University of Guelph; Linping Wang, University of Guelph

Katherine Vinson, University of Guelph Suppressing pathogens in the greenhouse setting was the focus of this study led by Dr. Youbin Zheng. Dr. Zheng selected composted and non-composted organic materials with potential pathogen suppression properties and mixed these materials with other components to form a variety of growing substrates. Pathogenprone ornamental plants such as begonia were then subjected to selected growing substrates. Substrates containing vermicasting or pine bark showed disease suppression, however results were not consistent.

Further reading: Guelph Green Roof Research

Reducing water applications

Youbin Zheng, University of Guelph; Mike Dixon, University of Guelph; Xiuling Tian, University of Guelph; Mary Jane Clark, University of Guelph; Linping Wang, University of Guelph; Katherine Vinson, University of Guelph

Managing water usage is a priority for ornamental growers. Dr. Youbin Zheng examined water application technologies and conducted a thorough literature review which identified some promising irrigation technologies for ornamental nursery plant production purposes. One technology in particular, a sensor-based automated irrigation system, was evaluated in a commercial nursery for pot-in-pot tree production and demonstrated that growers could cut their water usage by more than 50%.

Expand the adoption of precision plant based irrigation technologies to reduce water use in both greenhouse and nursery product

David Ehret, AAFC, Agassiz

Dr. David Ehret with Agriculture and Agri-Food Canada has evaluated a modified version of the CropAssist system developed for greenhouse tomatoes on other ornamental plants. Two greenhouse species and two nursery species, each of which differed in daily water requirements, were monitored for periods of up to 30 consecutive days. Results indicated that the CropAssist system effectively measured water uptake automatically and continuously. Automated monitoring of water use with load cells has been proven to be a simple and reliable technology for both greenhouse and nursery use and presents an opportunity for development into a commercially-available product.