Location: Fruit and Tree Nut Research
Project Number: 6042-21220-014-000-D
Project Type: In-House Appropriated
Start Date: Mar 4, 2020
End Date: Mar 3, 2025
Objective:
1. Improve pecan nut productivity by analyzing key horticultural issues that disrupt annual consistency, yield, and quality, and developing new or improved mitigation strategies. [NP305, C1, PS1B] (Previously reviewed and approved)
1.A. Determine if canopy exposure to nano-particles, in particular zinc and nickel nano-particles can improve health and longevity of pecan tree canopies.
1.B. Characterize horticultural traits of native pecan germplasm and identify genes of interest as a resource for development of new and improved cultivars.
1.C. Characterization of improved pecan rootstocks for uniformity of yield and enhanced productivity.
2. Reduce impacts of the most important pecan diseases on production, quality and uniformity of nutmeats. [NP305, C1, PS1B] (Previously reviewed and approved)
2.A. Characterize and identify novel ways to improve management of pecan scab in tree canopies based on inoculum sources, fungicide spray coverage, disease distribution and methods for disease management.
2.B. Determine dynamics of population genetic diversity of Venturia effusa in pecan orchards.
3. Develop new and improved pecan processing technologies, such as pasteurization and cracking/shelling, for improved storage, food safety, nutrition, and marketability. (NP305, C1 PS1B; NP 306, C1, PS1C) (New, for review)
3.A. Determine factors that influence the growth and/or survival of foodborne pathogens on the surface of whole and cracked pecans.
3.B. Evaluate the efficacy of novel technologies as mitigation strategies to reduce foodborne pathogens on pecans.
3.C. Identify, characterize, and model pecan and machine factors to improve halves yields in pecan cracking and shelling.
Approach:
This research aims to provide pecan farmers with improved, sustainable tree and disease management practices that stabilize yield in pecan (Carya illinoinensis) orchards and maximize postharvest nutmeat quantity and quality. The management tools and strategies will enable farmers to mitigate alternate bearing (AB) and yield loss caused by disease. AB is considered the most important biological problem facing pecan production: it is economically harmful, resulting in excessive year-to-year fluctuation in nut yield and kernel quality. Many biotic and abiotic factors can induce or increase the amplitude of AB. How factors associated with canopy health, particularly nutrition, rootstock, and disease affect AB represent some of the knowledge gaps that limit development of suitable tools for stabilizing nut production and reducing yield losses. Losses postharvest include physically damaged kernels due to postharvest processing, loss to biological contaminants and poor shelf life resulting in loss of quality and salability. The research addresses 1. Whether use of nano-fertilizers can provide a basis for more efficient nutrient management, stabilize and increase production of pecan, while ensuring better environmental security. 2. Phenotyping horticultural traits of native and improved pecan germplasm in conjunction with genome wide analyses. 3. Using genomics to identify markers for horticultural traits for use in the breeding program. 4. Characterizing the role of rootstocks in tree growth and productivity, to provide a basis for more uniform, consistent and thus sustainable production of pecan nutmeats. 5. Determining how inoculum sources of pecan scab (caused by Venturia effusa) contribute to the epidemic, and using this information to develop new disease management tools, thereby reducing the impact of scab in susceptible pecan cultivars. 6. Understanding the population genetics of the scab pathogen to underpin deployment of more durable host resistance in the future. 7. Using genomics to identify effector genes involved in scab pathogen virulence. 8. Developing novel nut shelling and associated processing techniques to minimize physical nutmeat damage, contamination, and loss of quality postharvest. and 9. Improving understanding of pre-harvest and postharvest environmental factors that impact pecan color, texture, oil quality, and phytochemical content to identify conditions that maximize duration of quality. To better understand food safety risks associated with pecans, the project will address factors that influence the survival and persistence of foodborne pathogens and identify effective mitigation strategies while maintaining nut quality. In order to maximize marketability, the project will explore means to cost-effectively increase intact pecan meat extraction by modifying parametrized process variables on existing processing equipment. A series of field and laboratory studies over the project duration will address the key knowledge gaps and provide greater knowledge and understanding to develop horticultural and food safety tools and strategies required for improved management and thus long-term sustainability of pecan.
