By: Forrest Scharf (PAg) Provincial Specialist, Fruit Crops
The 2015 Haskap Field day was held June 26 at the University of Saskatchewan’s (U of S) Horticulture Field Plots. Several interesting research findings were reported, attendees were able to sample the vast diversity of U of S haskap fruit genotypes, and opportunities to network with growers made for a fulfilling day. Along with numerous familiar faces from neighbouring provinces and states, there were three growers from Poland, accompanied by Dr. Stanislaw Pluta (a berry breeder from the Research Institute of Horticulture, Pomologiczna, Skierniewice Poland), as well as Bill Choi, who came to the event as representative of SK corporation of Seoul South Korea.
An introduction to haskap and the infrastructure at the Horticulture Field Lab kick-started the formal program for the day. A highlight of the introduction was seeing haskap grown inside a shade structure (the Horticulture Field Lab’s high tunnel covered with green netting) and comparing it to haskap grown outside in full sun. The shaded haskap appeared to be growing more vigorously.
Similar environmental response observations have been made with respect to haskap grown in open field areas, when compared to shaded and sheltered locations. Reduced exposure to full sunlight and drying winds seems to improve growth. This corresponds with research findings for the use of photo-selective netting used by fruit growers in Israel. More information about the properties of various photo-selective nets and how they are used is available here.
Following the tour of the lab buildings, attendees were invited to visit the seedling plots, where they were able to see phenotypic differences between haskap seedlings and sample the diversity of fruit tastes within the U of S’s collection. The Fruit Program’s Lonicera caerulea collection includes wild haskap from boreal regions across Canada, varieties sourced from Russia, Japan and the Kuril Islands, crosses obtained from emeritus Oregon State University researcher Dr. Maxine Thompson, and a vast number of crosses made at the U of S. The day’s participants were encouraged to taste the fruit and flag their favorite plants. For those that have not sampled the range of flavours within the university’s collection, it is worth paying a visit to munch on some of these little gems.
Some seedlings in the collection have a tendency to retain flower structures that normally fall off from the distal end of the fruit as the flowers dry out during early berry development. Each berry develops from an ovary connected to two flower structures. Usually a sheath of skin from the ovary completely covers the two internal berry structures, but in some genotypes the skin sheath does not always cover the fruit. Flavours in the collection vary significantly, and phenotypic differences (like leaf size, colour, plant height, width, etc.) can also be conspicuous. The flagged plants serve to help the U of S’s Fruit Research Program make selections for more advanced breeding.
In the afternoon, presentations summarizing recent U of S research findings were made. The first presenter was PhD candidate James Dawson, who highlighted some of the advances made in the haskap breeding program to date. Advancements include:
- Fruit selections with larger average mass;
- Better average sugar to acid ratios;
- Higher total anthocyanin levels;
- Higher total flavonoid content; and
- Greater phenolic content.
For those interested in haskap nutrient information, James’ presentations on Haskap nutrition, absorption, and nutrient fractions are available.
PhD candidate Bayartulga Lkhagvasuren was the second presenter; he provided information on the results of some of his greenhouse trials. Bayartulga compared the growth habit and production characteristics of Tundra versus Japanese cultivars grown in two greenhouses with different temperature settings (one in 15 C daytime and 10 C night, and the other under 23 C daytime and 18 C night). The Japanese cultivars took much longer to flower (24.6 days vs. 13.1 days for Tundra). Average yields were also higher in Tundra than the Japanese cultivars under both temperature settings. Individual fruit weights did not differ significantly, although Tundra fruit tended to be smaller in the warmer greenhouse and the Japanese cultivars tended to be larger under warmer conditions. Similarly, Tundra sugar content was higher under cooler growing conditions, whereas Japanese cultivars tended to have higher sugar content under warmer conditions. The Japanese cultivars had higher titratable acidity than Tundra in both greenhouses, and the Japanese cultivars had the highest titratable acidity under cooler greenhouse conditions. More greenhouse research is being conducted and Bayartulga is seeking to determine optimum spacing, light settings, cultivar compatibility and to develop some recommendations for organic greenhouse production.
The final presentation was made by Prairie Plant Systems Bio Products Manager Dr. Yeen Ting Hwang, who discussed large scale tissue culture propagation of fruit trees. Dr. Hwang defined what tissue culture propagation is, and described how the technique is utilized to regenerate large numbers of genetically identical plants from plant cells grown on agar media. Tissue culture media contains nutrients and hormones that promote specific types of growth. In some cases, volumes of identical plant cells are desired, so hormones that promote callus formation (masses of cells) would be used for that. In other cases, rooting may be desired and under those circumstances (in general) fewer nutrients are added to the media and a rooting hormone like, indole butyric acid (IBA), is added.
For more information about haskap research, please see ADF reports Haskap Breeding & Production Final Report, 2009; and Haskap Berry Breeding and Production March 2012.