|Grauke, Larry - L J|
Submitted to: Louisiana Pecan Growers Association Newsletter
Publication Type: Other
Publication Acceptance Date: 3/13/2000
Publication Date: N/A
Technical Abstract: The history of the rootstock research orchard at the LSU (Louisiana State University) Pecan Station is reviewed, and the recent observations made in that orchard are summarized for the pecan growers. Patterns of performance in orchards are influenced by the rootstock, with differences in patterns of budbreak being observed in young trees, which can influence patterns of damage in late spring freezes. Nutrient uptake was also influenced by rootstock, with trees on 'Moore' seedling rootstocks taking up more potassium than those on 'Elliott' and 'Riverside' seedling rootstocks. Trees having 'Apache' seedling rootstocks accumulated more boron than those on 'Elliott' and 'Riverside' seedling rootstocks. Canopy size varied as a function of rootstock, with trees grafted on 'Apache' seedling rootstocks having reduced canopy size as compared to those on 'Curtis' and 'Moore.' This research confirms that trees in the orchard can differ in performance on the basis of open-pollinated seedling rootstocks. For maximum uniformity in any orchard, the variable of rootstock should be controlled by specifying use of a single seedstock. The choice of that seedstock will vary by region. In Louisiana, the use of 'Moore' seedling rootstocks, as indicated by the research of Sitton and Dodge, is still recommended. The use of 'Apache' rootstocks, while common and possibly advisable in the western regions, is apparently a liability in northern Louisiana.