Trends in sweet cherry breeding
This is the second in a series of articles compiled by Lynn Long of Oregon State University Extension from research presented at an International Society for Horticultural Science cherry symposium, which he attended in Turkey in 2005.
Several posters were presented during the symposium on 0900 Ziraat, the most important cherry variety grown in Turkey. The cherry is being sold in the United States as Zing.
Turkey is the second-largest cherry exporter in the world, with 35,000 tons exported annually, just behind the United States at 40,000 tons. Nearly all of Turkey’s export cherries are 0900 Ziraat, and the vast majority of these cherries are marketed in Europe. Ten years ago, little was known about this variety in the West, and even now, most of our knowledge is purely incidental, consisting of fruit purchased in stores in western Europe.
The fruit seems to be high quality and firm, with mahogany skin and somewhat lighter flesh. The flavor is excellent and has been readily accepted by consumers. According to Dr. Kenan Kaynas and other researchers at the University of Çanakkale, bud burst (presumably first bloom) occurs nine days after Van (see table). Fruit ripens about one week after Bing.
Although growers in Turkey have been growing this variety for decades, little scientific research has been conducted until recently. Many growers in Turkey use Starks Gold as a pollinizer, but productivity of 0900 Ziraat remains low, especially on Mazzard rootstock. In an attempt to determine the best pollinizer for 0900 Ziraat, Kaynas’s researchers hand pollinated 0900 Ziraat with the pollen from 14 varieties. Interestingly, although 0900 Ziraat blooms late, some of the best pollinizers for this cherry turned out to be midseason bloomers such as Lapins and Van.
The length of bloom for 0900 Ziraat was 12 to 15 days. The table lists only the best performers. Three other varieties—North Wonder, Canada Giant, and Sunburst—had comparable bud-burst timing, but none equaled the fruit set percentage of the four varieties listed in the table.
Other varieties tested were Prime Giant, Celeste, Merton Late, Bing, Bigarreau Gaucher, Sweetheart, and Early Burlat. It is obvious that other varieties grown in the Pacific Northwest should be tested to determine the best pollinizers available to U.S. growers.
Dr. Masum Burak and other scientists of the Atatürk Institute looked at rootstock interaction with 0900 Ziraat. Gisela 5 provided a high survival rate of 94 percent, but nearly 50 percent of trees budded to Weiroot 158 died. Maxma 14, a rootstock that produces a semidwarf tree in France, produces a tree of nearly equal size to Mazzard under conditions in Turkey.
0900 Ziraat (or zing) fruit set
Fruit set percentage of 0900 Ziraat sweet cherry as a result of hand pollination with pollen from various pollinizers.
|Fruit set % of 0900 Ziraat||Bud burst||Petal fall|
|Starks Gold||28.3||March 22||April 7|
|Lapins||29.4||March 15||April 7|
|Lambert||29.2||March 15||April 10|
|Van||28.1||March 21||April 7|
|0900 Ziraat||00.0||March 30||April 19|