Location: Crop Germplasm Research
Project Number: 3091-21000-046-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: May 1, 2024
End Date: Apr 30, 2025
Objective:
The goal of this project is to establish a highly efficient regeneration system for pecan by working closely with the Cooperator. A successful project will provide the pecan industry with a rapid clonal propagation method that can be used for the production of disease-free plants. The success of this project will lay the foundation for the development of pecan plants possessing desirable traits through conventional breeding methods as well as gene editing techniques.
This research will aim to:
Objective 1: Obtain aseptic pecan plant materials. Aseptic plant materials are necessary and essential for downstream tissue cultivation. Preliminary efforts by the Cooperator utilized two techniques: surface sterilization with different disinfectants, and using isolated apical meristem tissues. They successfully obtained aseptic tissues using meristem tissues. The Cooperator will continue experimenting with different disinfectants and different plant tissue types.
Objective 2: Identify optimal conditions for in vitro tissue growth. Finding the right combination of growth media, plant hormones, and environmental conditions to stimulate the growth of healthy plantlets from explants can be challenging. Under certain experimental conditions, the isolated apical meristem tissues can grow and differentiate, forming adventitious leaf-like structures. The Cooperator will determine the right culture conditions to encourage tissue to form axillary buds and promote shoot proliferation.
Objective 3: Induce regenerated plantlet rooting and acclimatization. Once the Cooperator has successfully regenerated shoots, they will carry out a comprehensive investigation to optimize plant growth regulator combinations to induce the rooting of regenerated plantlets. Successful efforts will be followed by experiments to identify the conditions necessary to acclimatize rooted plantlets into conditioned soils.
Approach:
During the growing season, new shoots of 'Pawnee', 'Lakota', and/or 'Elliott' will be collected from the repository orchards and delivered to the Cooperator. Sampling will be conducted by ARS every two or three weeks, depending on the Cooperator's needs. If late-season tissue is needed after full leaf expansion, ARS will harvest young tissue from stump sprouts for breeding lines from abandoned basic breeding program (BBP) orchards. Data analysis will be done in conjunction with the Cooperator.
