Performing Department
(N/A)
Non Technical Summary
Fruit rot diseases caused by several pathogens, namely Botrytis cinarea, Colletotrichum acutatum,and Neopestalotiopsis sp., are economically impactful in strawberry nurseries, fruiting fields, grocery stores, and homes worldwide, especially where warm and wet conditions provide the pathogen with the ideal environment to cause pre- and postharvest yield losses. Commercial strawberry varieties benefit from being resistant to multiple fruit rot diseases. Favorable alleles for disease resistances and bother traits may exist in wild relatives and are becoming more accessible through modern, data-driven breeding approaches informed by knowledge of genetic relationships and molecular diversity. The objectives of this proposal are aligned with the Farm Bill priority of plant health and production and plant products under the program area of Plant Breeding for Agricultural Production and specifically addresses breeding for "improved crop productivity, efficiency, quality, performance, and local adaptation to biotic and abiotic stress." Through the research outlined in this proposal we will expand our knowledge of genetic resistance to multiple fruit rot pathogens and develop tools to identify and select for QTL that underlie desirable variation. Specific objectives will address 1) the accessibility and availability of donors of genetic resistance that exist in public germplasm collections (USDA NCGR GRIN); 2) the relationship between fruit quality traits that affect consumer preference and the proclivity to be infected; 3) the development of breeding strategies that simultaneously improvement of fruit rot disease resistance that do not eliminate consumer-focused fruit quality; and 4) the need for the development of cost-effective,molecular marker tools for strawberry breeders.
Animal Health Component
75%
Research Effort Categories
Basic
25%
Applied
75%
Developmental
0%
Goals / Objectives
The proposal expands on the research themes the UC Davis Strawberry Breeding Program has focused on for the past eight years: improving disease resistance of strawberry cultivars to multiple pathogens. This proposal will facilitate research and initiate breeding for resistance to three relevant fruit-rotting pathogens, specifically Neopestalotiopsis sp., Colletotrichum acutatum, and Botrytis cinerea. This project comprises four main objectives:Objective #1: To significantly increase the knowledge of disease resistance donors, cultivars, and genetic solutions for multiple rot resistance (MRR) to Neopestalotiopsis sp., Colletotrichum acutatum, and Botrytis cinerea through in-field screening and genome-wide association. To achieve this goal we will (a) assess the frequency of resistance vs susceptibility to Neopestalotiopsis sp., Colletotrichum acutatum, and Botrytis cinerea in a large diversity panel and bi-parental breeding populations, (b) identifying quantitative trait loci (QTL) associated with favorable alleles, if present, and (c) developing cost-efficient, haplotype-specific molecular markers for marker-assisted selection (MAS) for the discovered QTL.Objective #2: To maintain superior productivity and improve quality during disease resistance improvement by accounting for genetic covariance between disease resistance and fruit quality to enhance the value of new cultivars. We will improve the productivity and profitability of strawberry cultivars by (a) measuring the genetic covariance between key fruit quality traits, including size, sugar:acid ratio, anthocyanins, vitamin C, firmness, and multiple disease resistance; (b) developing early, non-destructive phenomic tools for predicting fruit resistance and susceptibility using near-infrared spectroscopy (NIRs) and hyperspectral imaging; (c) developing and deploying phenomic breeding strategies that incorporate information on multiple trait covariances contributing to commercial value.Objective #3: To improve the ability of strawberry breeders to incorporate stacked disease resistance through genome and marker-informed breeding strategies. We will improve the rate of genetic gain for expensive-to-measure traits by (a) improving breeding practices through the implementation of multi-trait genomic selection (GS) with phenomics and correlated fruit traits and (b) conducting simulations with empirical validation to build internal and external confidence in data-driven decision making and predictive frameworks.Objective #4: To increase the accessibility to high-quality germplasm resources to public and private programs. We will disseminate information regarding beneficial alleles in available germplasm and improve the accessibility of high-value donors by (a) updating available data in the USDA GRIN and NCGR system and (b) extending knowledge of beneficial alleles to public and private partners.Our long-term goals are 1) to provide the genetic resources and breeding formulas to stakeholders, 2) to release cultivars with high yield, excellent shelf life, resistance to soil-borne diseases, resistance to fruit rot diseases, and preferred fruit quality, and 3) to release germplasm accessions with high concentrations of favorable alleles to deliver value to a diverse set of stakeholders in CA, the US, and around the world.One of our goals is to train the next-generation of problem solvers. Our trainees include undergraduate and graduate students and postdoctoral scholars in horticulture, plant breeding, genomics, bioinformatics, molecular biology, and plant pathology. Trainees will have the opportunity to extend knowledge and interact with diverse stakeholder communities through field days, workshops, on-farm research, cooperative extension and scientific meetings, and one-on-one and small group activities.We expect the proposed initiative to improve the lives of farmers and rural communities by preventing losses to diseases that adversely affect strawberry production. The solutions we deliver are expected to reduce production risk, improve disease diagnosis, prevention, and management, decrease pesticide usage, facilitate the transition from fumigant-dependent to alternative production systems, and enable the expansion of organic production. One of the goals of this research will be the development and deployment of cultivars with unmatched resistance to a broad spectrum of diseases.
Project Methods
The primary efforts associated with our initiative include the delivery of science-based knowledge through: (a) formal classroom and laboratory instruction; (b) informal laboratory and field research and development activities: (c) experiment design and planning, field experiment preparation, maintenance, and management; (d) greenhouse and laboratory experiment design and analysis; (e) workshops on genome-informed breeding and genome-editing; and (f) grower education, extension, and outreach programs.One of the primary methods for evaluating the impact of our work on growers (one of the intended audiences) will be the adoption of disease resistant cultivars, e.g., with over half of the acres in California planted to NPT and anthracnosesusceptible cultivars, we can directly estimate how our work increases the acreage planted toresistant cultivars from industry planting surveys. Similar metrics will be collected for the other diseases we are investigating.Our impact on the scientific community (one of the other intended audiences) will be evaluated by documenting: (a) the number and impact of peer-reviewed publications (measured by accesses and citations); (b) the quality and quantity of open-source data deposited in public databases and downloads from open-source data repositories; (c) direct feedback at scientific meetings and workshops; and (d) direct interactions with scientists in the broader scientific community.