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ARS Home » Northeast Area » Kearneysville, West Virginia » Appalachian Fruit Research Laboratory » Innovative Fruit Production, Improvement and Protection » Research » Publications at this Location » Publication #163768


item Krewer, G.
item Jacobs, J.
item Takeda, Fumiomi - Fumi
item Mullinex, Ben

Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: 4/25/2004
Publication Date: 6/15/2004
Citation: Krewer, G., Jacobs, J., Takeda, F., Mullinex, B. 2004. Dormex increases blackberry yield. Hortscience. 39:662; 2004

Interpretive Summary:

Technical Abstract: Blackberry industry that ships fruit for long distances is rapidly developing in South Georgia as a compliment to the 6000 acre (2429 ha) blueberry industry. Thornless blackberries from the Univ. of Arkansas are the preferred type in this area because of their excellent fruit quality. However, they have yielded poorly following mild winters. In 2002, Dormex (50% hydrogen cyanamide) at 0, 2, 3, and 4%, and thidiazuron (200 ppm a.i., with 2% dormant oil) were tested on 'Arapaho', 'Navaho' and 'Apache' cultivars in a winter with 584 hours of temperatures below 7 ºC. Dormex at 3 and 4%, but not thidiazuron, accelerated foliar development and slightly advanced bloom and harvest periods. In 2003, a year with 906 hours of winter chill, Dormex was tested on 'Apache' and 'Navaho'. Dormex at 3% again promoted early spring growth and increased yield in weeks 1, 2, and 3 for 'Apache' and weeks 1 through 5 for 'Navaho'. Yield at week 5 for 'Apache' and week 6 for 'Navaho' was greater in the control than in plants treated with 3% Dormex. Dormex at 3% increased yield during the commercial market window by 89% in 'Apache' and 57% in 'Navaho'. Dormex appeared to increase budbreak in the mid and lower part of the canopy. The results indicate that Dormex applications can be used as a tool to improve early season and overall plant yield in blackberries.