Location: Crop Germplasm Research2012 Annual Report
1a. Objectives (from AD-416):
Produce improved pecan scion cultivars and rootstocks by making controlled crosses, collecting tree performance data, and integrating this data into a large central database used to make selection decisions and determine heritability of important genetic characteristics.
1b. Approach (from AD-416):
Crosses between pecan clones are made, seed are planted, and seedling trees are initially grown in the greenhouse. Scions are collected from these small trees and grafted or budded to large pollarded trees in the orchard. As these scions produce nuts, they are evaluated for tree growth habit, leaf health, and nut samples are collected. The very best clones from this initial selection phase are selected to test in the advanced testing program. After 15 years in this phase, the best clones are released to growers as improved cultivars with Native American names. Data are also used to determine heritability of important genetic characteristics. Some superior clones may also be released as improved rootstock parental material, based upon superior growth, mineral uptake ability, and general tree health.
3. Progress Report:
The goal of this project is to evaluate large numbers of pecan accessions for desirable traits, including nut production, nut quality, and insect and disease resistance (primarily scab disease). Work during FY 2012 focused on the Basic Breeding Program (BBP) of the National Pecan Genetics and Breeding Program, with over 8,000 seedlings in various stages of evaluation. Over 600 seedlings (clones) from control crosses made in FY 2010, and 129 clones produced in FY 2011 were screened for scab resistance. Scab-resistant clones were grafted to large pecan trees that had been severely cut back or pollarded. This technique hastens fruiting and evaluation, mainly for precocity (early bearing) and nut quality. Older superior selections identified in the BBP during FY 2012 were entered into the National Pecan Advanced Clone Testing System (NPACTS) at several national sites to determine adaptability to specific environments. Data and performance information from several NPACTS tests from across the U.S. were analyzed and added to master NPACTS databases in FY 2012. Work by this project, as it continues, will facilitate development of new pecan varieties for U.S. growers that will enhance profitability, provide a higher quality product for the consumer, and be more environmentally sustainable because of reduced requirements for pesticide application in pest and disease control.