Recipient Organization
MISSISSIPPI STATE UNIV
(N/A)
MISSISSIPPI STATE,MS 39762
Performing Department
Pontotoc Ridge-Flatwoods Branc
Non Technical Summary
Sweetpotato foundation seed programs began in the 1940s with the goal of managing incidence of mutations. CA began using virus-tested plants in the 1970s to control russet crack and LA and NC adopted virus-tested plants in the 1990s to reduce cultivar decline. Inclusion of sweetpotato in the NCPN in 2015 provided a capacity building opportunity by harmonizing collaborative research and extension efforts across the nation based on facilities & resources, disciplinary knowledge, and the demand/perception of CCFS programs by stakeholders in each state. As a result, clean plant centers in AR, CA, LA, MS, and NC have adopted common standards and protocols for virus testing and have strived to increase the number of clean foundation plants produced for CCFS programs. It is estimated that the number of clean plants increased about 94 million (18.6%) between 2015-2019 and clean plant centers continue to try and discover ways to expand production. However, the mission of NCPN is to "conduct diagnostic and pathogen elimination services and to establish foundation blocks of pathogen-tested plant materials to supply nurseries, growers, and state certification programs". There has been no funding available to support research and very little for extension or service activities throughout the rest of the CCFS system.Virus re-infection. Past research in LA and NC indicates that re- infection of CCFS with potyviruses can be very rapid in southeastern U.S., even in the initial stages of increase. As part of a prior SCRI-funded project (No. 2009-51181-06071), a lot was learned about the epidemiology of re-infection of CCFS with potyviruses in LA and MS by aphid vectors and involvement of morningglory alternative hosts. Sources of inoculum, efficiency and mechanisms of transmission, and peak transmission periods were identified. However, since that project there has not been funding to support needed research on how to use the epidemiological information to develop programs to manage virus re-infection.Recent Diseases. In addition to viruses that systemically infect sweetpotato planting material, two major disease problems have emerged on storage roots, in part because they can be transferred on seed roots: black rot and GRKN. Ongoing research on black rot in NC and LA focuses on finding resistance to the disease and fungicidal controls. One goal is to find resistance that reduces transmission from infected seed roots to sprouts, thereby increasing opportunities to harvest clean plants from beds. Ongoing research on GRKN also focuses on resistance, but another project at the USDA Vegetable Lab in Charleston, SC is aimed at finding methods to detect the presence of GRKN in storage roots which might be used by state crop improvement associations as part of the seed certification process.Epigenetic Effects. Each clean plant center may have different ways of maintaining clean plant materials between seasons either as "Mother Plants" in a greenhouse environment or as tissue culture in the lab. The question was raised as to whether these methods had any epigenetic effects that might alter the performance of the plants. A project was initiated in LA to investigate that possibility, using Murasaki and Covington varieties comparing greenhouse vs. tissue culture maintenance in optimal and stressful tissue culture conditions. These research efforts need to be expanded.Production Management. Most extension publications recommend use of 'high-quality planting materials', but seldom has that been defined for commercial sweetpotato production. Research in LA and Australia indicated that seed root size and spacing in plant beds will affect slip production. In addition, slip length and number of nodes, sucrose, and inorganic phosphorus availability can affect storage root yield in commercial production. However, recommendations for 'high-quality' plant production are still lacking. If a trend to horizontal slip transplanting persists, it will change requirements for slips to longer but potentially fewer slips per acre. Also, row covers have been used to maintain early-season warmth and exclude virus vectors, but only casual observations have been made on slip quality.Economics. An economic benefit study conducted in China determined the use of CCFS increased the rate of return by 202% based on changes in sweetpotato yield. Even though commercial production yield potential is higher with the use of CCFS, the overall net-profit can be affected by the nature of explicit costs associated with expense of clean plant material. The price of greenhouse-grown clean plant material sold from clean plant centers is different from state to state. This could be due to capital investment, operating expenses, production practices, number of plants produced, and how the plant material is packaged (cut-slips, large potted plants, small plants in flats, etc....). A production budget developed for a 30-by-96-foot greenhouse structure indicates that the approximate breakeven points for producing 40,000, 60,000 or 80,000 slips $0.65, 0.43, and 0.32/slip. This is a starting point to begin a more unified price structure between clean plant centers.These recent and on-going activities will be built upon to develop a future SCRI-SREP proposal using methods that have contributed to successful planning for natural resource and agricultural based organizations. The project team has conducted successful planning workshops for Mississippi Forestry Association, the Mississippi Women for Agriculture Organization, Community Forestry Associations, multiple municipalities, and to address regional issues with oil and gas policy. The methodology can be found in organizations using the methods in an article by Gordon et al., 2013 titled "Leadership and Engagement for Natural Resoource Organizations: A case study in Mississippi".
Animal Health Component
35%
Research Effort Categories
Basic
35%
Applied
35%
Developmental
30%
Goals / Objectives
This planning project will build capacity through collaborative relationships between clean plant centers, industry representatives, and multi-state teams of leading biological, physical, and social scientists to deliver efficient and effective solutions to issues confronting foundation seed used for commercial sweetpotato production. The goal of this planning project is to develop a large SCRI-SREP proposal that will address critical needs of the U.S. sweetpotato industry using stakeholder input to identify and prioritize research and educational objectives that will ensure a sustainable supply of high quality certified clean foundation seed (CCFS) in the future. All CCFS programs, which begin with virus-tested clean plant material, have experienced accelerated growth across the U.S. since sweetpotato joined the National Clean Plant Network (NCPN) in 2015. CCFS is important because sweetpotato plants are reproduced by vegetative propagation techniques and systemic pathogens, especially viruses, can accumulate in the propagation material and contribute to "cultivar decline", affecting yield, skin color, root shape and storage quality. Foundation seed programs are the sole source of planting material for commercial growers that is demonstrably clean, but unfortunately any sweetpotato can be used for propagation including those that have become re- infected during seed increase in the field as well as excess commercial stock that was never intended for use as seed. Therefore, it is important for growers to begin with foundation seed that is certified as clean seed by state crop improvement agencies. Since CCFS is the cornerstone of U.S. sweetpotato production, it is critical that we address several major problems that challenge the production, utilization, and sustainability of high-quality clean seed in the future.• We do not know how different propagation schemes, crop production practices, locations, or years affect the rate of re-infection and hence the quality and economic value of the seed. Although virus-tested clean seed have been shown to reduce cultivar decline, it has become evident that re-infection happens routinely in commercial operations. Currently, there are no data-driven recommendations on how to reduce re-infection.• Can we reduce the risks associated with using roots for seed by increasing the production of clean, certified plant material? Traditional sweetpotato propagation has relied on sprouting seed roots in field-beds to produce plant slips for transplanting in commercial production fields. The use of seed roots dramatically increases the risk of introducing soil-borne pathogens that can infect slips and compromise quality. In 2013, sweetpotato black rot caused by Ceratocystis fimbriata began to appear in NC and within two years it spread to other sweetpotato producing states. The highly destructive GRKN, Meloidogyne enterolobii was reported in NC during 2011 and SC by 2017. Sweetpotato producers across the U.S. purchase some seed from across state lines, which has provided the means for rapid distribution of black rot and GRKN to new areas. There are currently no efficacious or cost-effective management options once GRKN has entered a production system.• What is the quality of clean plant material currently provided to commercial growers, can this be improved, and how can we provide assurance of its quality? The risk of mutations in sweetpotato varieties has been reduced with micro-propagated clean plant material. However, epigenetic regulatory mechanisms may change based on frequency and type of micro-propagation techniques utilized in the lab and greenhouse. Epigenetic variations or mutations in sweetpotato cultivars may not be expressed until they enter commercial field production and may reduce crop yield and quality. In addition to recognizing how production practices affect incidence of mutations and re-infection by viruses, there is a need to objectively assess seed lots to determine the actual incidence of these problems and provide support for growers to make decisions on the quality of their seed and likely outcomes from its use. This will require characterizing previously unrecognized mutation/epigenetic effects, viruses, and developing specific assays for them and other pathogens such as M. enterolobii and C. fimbriata. Even for well recognized viruses, we have no systematic information to know if there are strain variations in viruses that affect our ability to detect them. Are there markers (e.g. virus incidence or molecular indicators of epigenetic effects, etc.) that could be used as indicators of seed quality? Filling these knowledge gaps will contribute to the sustainability of U.S. sweetpotato seed programs.• Anecdotal reports suggest that growers in different states have very different perceptions and attitudes regarding clean plants. There is a need to understand how growers select what they will use for seed, to provide scientifically sound information on seed quality and its economic value, to develop a strategic plan for the industry that will direct future research and extension efforts, and provide an approach to improving both the quantity and quality of clean plants.The long-term goal of this CleanSEED planning project will be to address the critical needs of the sweetpotato industry by identifying opportunities to leverage progress made by U.S. Clean Plant Centers to increase certified clean plant material across the nation. The planning project will identify stakeholders' priorities, gaps in knowledge, educational needs, and research areas that are needed to address these priorities. The planning project will then organize research teams to lead these efforts and develop a future SREP proposal that will address the barriers to clean plant accessibility and use, meet stakeholder priority needs, and enhance the sustainability and profitability of the sweetpotato industry.
Project Methods
The project will entail a logical process that brings together a multi-disciplinary team that will develop a research proposal to improve the viability and sustainability of the sweetpotato industry. The project steps and expected outcomes are below. Process evaluation will track completion of the project's steps through a comparison of actual to planned effort. Evidence of completion will consist of the existence and compilation of documents and databases. Outcome evaluation will also be conducted to demonstrate the results and benefits of the project's activities. Evaluation methods accompany each project step and expected outcome.Project StepsStep 1. Identify the gaps in knowledge, education and research needs through a needs assessment survey of industry stakeholders.• Evaluation: Existence of the sweetpotato stakeholder survey and database of completed needs assessment survey(s) that include demographic data.Step 2. Formalize the CleanSEED Planning and Organization Committee aka CPOC with scientists from multiple sweetpotato producing states. • Evaluation: Existence of CPOC distribution list. Step 3. Conduct monthly conference calls to organize the 2-day planning work session. • Evaluation: Existence of attendance logs from monthly conference calls.Step 4. Each state's representative with CPOC will select and invite stakeholders from their state to participate in the planning process.• Evaluation: Existence of an invitation to the 2-days work session, compilation of invited individuals from each state, and database of confirmed RSVPs (including stakeholder or scientist sector and state being represented).Step 5. Hold a 2-day work session and conduct a planning process to develop the foundation of an SCRI- SREP proposal. The process will identify priority issues, resources, and steps to address the critical research and extension needs regarding the adoption of clean plant technology.• Evaluation: Existence of attendance logs from 2-day work session (including state and affiliation) and writing plan for an SCRI-SREP proposal (e.g., rationale, goals, organizational structure, and individuals responsible for proposal activities). Step 6. Project team finalizes research and extension plan and submits proposal. • Evaluation: Existence of an SCRI-SREP proposal Step 7. Research proposal is funded, and research, outreach, and education action steps are implemented.• Evaluation: Appropriate evaluation designs and methods for process evaluation of research, outreach, and education action steps in the SCRI-SREP proposal will be determined during the writing process to ensure a fit among strategies, desired benefits, target audiences, and timeline. Step 8. Document progress and outcomes through evaluation. • Evaluation: Compilation of all data/evidence/outputs described.Project Outcomes1. Collaboration and engagement occur across the sweetpotato industry, research and extension scientists, and clean plant centers to address critical needs of the sweetpotato industry. 2. Awareness of existing resources on sweetpotato clean seed is increased.3. Understanding of stakeholder priorities, gaps in knowledge, educational needs, and research needs related to sweetpotato clean seed is enhanced.• Evaluation: To evaluate short-term outcomes 1-3, document analysis of conference call minutes and work session notes will show the extent of collaboration and engagement across stakeholder and scientist according to topic; awareness of existing resources on CCFS; and understanding of stakeholder priorities, knowledge gaps, educational needs, and research needs related to CCFS. The nature of the conversations among participants will show the extent to which the needs and interests of all participants are considered.4. SCRI-SREP proposal to address the sustainability of U.S. sweetpotato CCFS programs is submitted.• Evaluation: To evaluate medium-term outcome 1, official confirmation of formal submission of an SCRI-SREP proposal will show that scientists and stakeholders on the original planning project team were actively engaged in a plan to improve the sweetpotato industry, as well as demonstrate they understood industry priorities, needs, assets, and resources.5. Collaboration and engagement are expanded beyond the initial CPOC through more diverse representation of sweetpotato industry stakeholders (e.g., growers and regulatory personnel from additional states, new and experienced certified seed producers).• Evaluation: To evaluate medium-term outcome 2, document analysis of continued conference call attendance logs and meeting minutes will show the addition of new participants to the group and their contributions to continued work. As stakeholder surveys are repeated, analysis of demographic data will also show representation of stakeholders and scientists.6. SCRI-SREP proposal is funded and activities are completed, thus financial and educational resources lead to improvements in the sweetpotato industry.7. Sweetpotato industry produces highest quality planting material that reduces problems with dissemination of soil-borne pathogens, re-infection with viruses, minimize mutation and epigenetic issues, and meets the needs of the industry as it expands and becomes more geographically diverse.• Evaluation: The length of this planning project is conducive to evaluating only short- and medium-term outcomes. If the desired short- and medium-term outcomes are achieved, theory of change models suggest that the desired long-term outcomes of quality sweetpotato planting and production should occur. Appropriate evaluation designs and methods for assessing outcomes related to the research, outreach, and education action steps in the SCRI-SREP proposal will be determined during the writing process to ensure a fit among strategies, desired benefits, target audiences, and timeline.