Evaluation of Kiwifruit
We have been evaluating potential kiwifruit varieties at the NWREC for commercial production since 1990.
A summary of what we have learned to date:
- Iodine staining of starch in 'Ananasnaya' hardy kiwifruit is not useful as an indicator of harvest maturity.
- Harvest Brix of 'Ananasnaya' significantly affected fruit quality – consumers did not prefer fruit harvested at low Brix (6 Brix). Aroma and flavor were rated higher on fruit that were refrigerated after harvest than on those that were not.
- 'Ananasnaya' flowers were thinned [0% (control), 15%, 30%, and 50% flower bud removal (2-5 June)]. The average yield of vines thinned 50% was significantly less than that of control vines. However, marketable yield from vines thinned 15%, 30% and 50% was not significantly different from control vines. Thinning, regardless of severity, increased average fruit volume and king fruit volume by 18% and 27%, respectively, compared to control vines. King fruit were more affected by thinning than the two adjacent lateral fruit in the cluster. Thinning before bloom had no effect on percent soluble solids, seed number or total seed weight per fruit. At the present time thinning does not seem practical.
- Pruning studies have shown that pruning hardy kiwifruit vines, relatively severely, increases fruit size and uniformity of ripening.
- Edible coatings may be used to reduce desiccation of harvested 'Ananasnaya'
- Overhead shading (~ 50%) of 'Ananasnaya' vines for 2 months prior to fruit harvest, led to the greatest reduction in flower number the following season confirming that the period before fruit harvest is an important time for flower bud development (for next year's crop) in this species.
- In 'Ananasnaya', the origination of one-year-old fruiting wood had no effect on percent fruitful shoots. One-year-old canes produced fruitful shoots along their entire length, but were most productive from nodes 6 to 26. There was no relationship between yield per vine and return bloom the following year. Fruit set was 74%.
Other faculty involved in this project are: Gil Buller (Senior Research Assistant, NWREC) and Chad Finn and Kim Hummer (USDA-ARS); Marieles Pescie, Chantalak Tiyayon, and Connie Landis Fisk (former M.S. graduate students, Dept. Hort.)
Bernadine C. Strik, Professor
Department of Horticulture & Berry Crops Research Leader
North Willamette Research & Extension Center
Strik, B. 2005. Growing kiwifruit (revision). OSU Extension pub. PNW 507. 23 pp.
Strik, B. and K. Hummer. 2006. 'Ananasnaya' hardy kiwifruit. J. Amer. Pom. Soc. 60:106-112
Fisk, C.L. , A.M. Silver*, B.C. Strik, and Y. Zhao. 2008. Postharvest quality of hardy kiwifruit (Actinidia arguta 'Ananasnaya') associated with packaging and storage conditions. Postharv. Biol. and Tech. 47 (Feb):338-345.
Landis-Fisk, C. , B.C. Strik, and Y. Zhao. 2006. Iodine staining of starch in 'Ananasnaya' hardy kiwifruit is not useful as an indicator of harvest maturity. HortTech. 16:655-658.
Fisk, C.L. , M. McDaniel, B. Strik, and Y. Zhao. 2006. Physicochemical, Sensory, and Nutritive Qualities of Hardy Kiwifruit (Actinidia arguta 'Ananasnaya') as Affected by Harvest Maturity and Storage. J. Food Sci. 71:204-210
Pescie, M. and B. Strik. 2004. Thinning before bloom affects fruit size and yield of hardy kiwifruit. HortScience 39:1243-1245.
Tiyayon, C. and B. Strik. 2004. The influence of time of overhead shading on yield, fruit quality, and subsequent flowering of hardy kiwifruit, Actinidia arguta. NZ J. Crop and Hort. Sci., 32:235-241.
Tiyayon, C. and B. Strik. 2003. Effect of fruiting cane origin on fruitfulness of hardy kiwifruit, Actinidia arguta. NZ J. Crop and Hort. Sci., 31:179-186
Tiyayon, C. and B. Strik. 2003. Flowering and fruiting morphology of hardy kiwifruit, Actinidia arguta. Acta Hort. 610:171-176.