Summerland Research and Development Centre

Transmission electron microscope images of four bacteriophages capable of reducing Salmonella densities in vitro. Phage SI1 reduced Salmonella populations on sprouting alfalfa seeds by ~2.5 log CFU/g. Alfalfa sprouts have been linked to numerous North American outbreaks of Salmonella in recent years. Conventionally, treatments involving chlorine, heat, and irradiation are used for alfalfa seed sanitation. However, such treatments may be highly variable in their efficacy for p...athogen control and/or detrimental to sprout quality, therefore negatively perceived by consumers advocating for natural alternatives. The usage of bacteriophages for pathogen control in sprouts has been previously explored, although with conflicting and inconsistent results. Lytic phages, viral predators of bacteria, represent an attractive approach as they provide several advantages compared to conventional treatments, such as their high specificity for bacterial targets and their ubiquity in nature. In this study, four Salmonella phages were isolated from British Columbia, Canada and characterized to assess their potential to control Salmonella. In particular, a significant (p < 0.05) reduction of 38.3 3.0% of viable Salmonella cells was observed following two h of phage treatment with phage SI1. On days two to six of the sprouting process, reductions of Salmonella were also observed, but were not significant compared to the control (p > 0.05). It was further demonstrated that the sprout yield was not significantly (p > 0.05) affected by phage treatment. These results highlight the potential of phages recovered from the British Columbia environment for use as biocontrol agents against Salmonella. Fong K, LaBossiere B, Switt AIM, Delaquis P, Goodridge L, Levesque RC, Danyluk MD, Wang S. 2017. Characterization of four novel bacteriophages isolated from British Columbia for control of non-typhoidal Salmonella in vitro and on sprouting alfalfa seeds. Front. Microbiol. 8:2193. https://doi.org/10.3389/fmicb.2017.02193 #surdc #foodsafety #agriculture #canada #pathogens #phages #bacteria #salmonella

Image: Effect of row cover on incidence of flesh browning (soggy breakdown) in 'Ambrosia' apples after 5 months of air storage at 0.5 C. Note: the apples from the silvered Mylar row cover treatment are the only apples with flesh browning symptoms. Two approaches for enhancing red blush color in Ambrosia apple were evaluated; 1) reflective row covers, or 2) application of foliar phosphorus-rich sprays, both applied several weeks before anticipated harvest. Two experiments ...were conducted, the first to evaluate a white reflective row cover versus foliar phosphorus spray and the second to evaluate two types of reflective row cover, one being made of a woven white polyethylene and the other a solid silvered Mylar. The comparative effect these pre-harvest treatments on at-harvest fruit quality and quality after storage were assessed. It was determined that foliar phosphorus sprays or either of the two types of reflective row covers resulted in similar enhancement of red blush colour with no negative effects on at-harvest quality. However, it was found that after 8 months controlled atmosphere storage (1 % O2 + 1 % CO2 at 0.5 C), apples from the phosphorus foliar spray treatment developed significant greasiness and sooty mold (blotch) on the skin surface, but neither were found on apples from the reflective row cover treatment. In the second experiment, after 5 months of air storage at 0.5 C, the apples from the silvered Mylar reflective row cover treatment developed severe storage-related disorders (soft scald and soggy breakdown) whereas apples from the white reflective row cover treatments very slight soft scald and no soggy breakdown. These results indicate that when pre-harvest treatments are applied to apples, that post-storage quality effects should be evaluated. Toivonen P, Lu C, Stoochnoff J. 2019. Postharvest quality implications of pre-harvest treatments applied to enhance Ambrosia apple red blush color at harvest. Canadian Journal of Plant Science 99: 4049 dx.doi.org/10.1139/cjps-2018-0193 2020 Her Majesty the Queen, as represented by Agriculture and Agri-Food Canada (AAFC) #apples #horticulture #agriculture #britishcolumbia #okanagan

Image: Rod shaped particles ofWasabi mottle virusimaged with a Transmission Electron Microscope after being extracted from leaf sap. Agriculture and Agri-Food Canada and Simon Fraser University researchers successfully isolated and described a new virus to wasabi in North America wasabi mottle virus. By characterizing the symptoms caused by this viral infection leaf mottling and vein-clearing, in extreme cases with necrotic lesions growers will be able to identify inf...ected plants and take appropriate management measures to reduce the spread among their crops. Using electron microscopy and genetic detection techniques, they were able to identify what species of virus was present in the plants. Further genetic investigations linked it to closely related strains of the virus in Taiwan and in Japan, where it was previously known. After identification and description of the virus, an isolate was contributed to the Canadian Plant Virus Collection, to be maintained so that future researchers have access to this strain. MacDonald JL, Punja ZK, Xiang Y, Bouthillier MJ, Reade R, DeYoung RM, Bhagwat B, Betz EC, Li YQ, Chen X. 2020. First report of Wasabi mottle virus causing ringspot and vein-clearing symptoms on wasabi (Wasabia japonica) in North America. Canadian Journal of Plant Pathology. http://doi.org/10.1080/07060661.2020.1805642 (C) Her Majesty the Queen, as represented by Agriculture and Agri-Food Canada (AAFC) #science #horticulture #wasabi #virus #microscopy #agriculture #canada #britishcolumbia #summerland #research #disease #phytopathology

A recent publication authoured by #SuRDC scientists was featured on the cover of the American Journal of Enology and Viticulture. Congratulations to them all! For the article, please see: Bowen P,Bogdanoff C,Poojari S,Usher K,Lowery T,Úrbez-Torres JR. 2020. Effects of Grapevine Red Blotch Disease on Cabernet franc Vine Physiology, Bud Hardiness, and Fruit and Wine Quality. Am J Enol Vitic.ajev.2020.20011... https://www.ajevonline.org//ear/2020/07/09/ajev.2020.20011 #enology #phytopathology #virus #grapes #wine #winegrapes #agriculture #horticulture #okanagan #science #viticulture #summerland #britishcolumbia #canada #farm #farming #winemaking

Image: 'Royal Gala' apples at a very early (image 1/2) and at an optimal harvest date (image 2/2). The early harvested apples do not display the 'striped' red blush that those harvested a the optimal date. The unique 'striped' red blush is an important market attribute for this popular cultivar. The research reported in this paper demonstrates that summer temperature patterns in two years (2016 and 2017) in the Okanagan Valley of British Columbia were associated with differ...ences in the time of ripening and internal quality of ‘Royal Gala’ apples. In the summer that the night temperatures are cooler (2016), the fruit accumulated 30% more percent dry matter (i.e. the relative content of all components in the fruit that were not water). In 2016, when the ‘Royal Gala’ apples were 30% higher in percent dry matter, the apples were found to ripen 20 days later and the fruit were 24% firmer as compared with apples harvested in 2017. The soluble sugars and acidity contents (associated with flavor to a consumer) were also higher at harvest in 2016 as compared with 2017. The firmness, soluble sugar and acidity contents remained higher after three and six months of storage in controlled atmosphere conditions (0.7 % oxygen and 1 % carbon dioxide) at 0.5 C for apples harvested in 2016 as compared with those harvested in 2017. These results show that yearly climate patterns can have significant influence on ripening dates and internal quality of ‘Royal Gala’ apples at harvest and after six months of storage. Toivonen PMA, Lannard B. 2020. Dry matter content association with time of on-tree maturation, quality at harvest and changes in quality after controlled atmosphere storage for ‘Royal Gala’ apples. Canadian Journal of Plant Science, Published on the web 30 September 2020. https://doi.org/10.1139/CJPS-2020-0124 (C) 2020 Her Majesty the Queen, as represented by Agriculture and Agri-Food Canada (AAFC) #science #okanagan #apples #research #horticulture #agriculture #farming #orchards #orcharding #treefruits #britishcolumbia