Source: KENTUCKY STATE UNIVERSITY submitted to
PAWPAW PATCH GENETIC DIVERSITY AND CLONALITY AND ITS IMPACT ON THE ESTABLISHMENT OF INVASIVE SPECIES IN THE FOREST UNDERSTORY
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0218531
Grant No.
(N/A)
Project No.
KYX-90-09-1MS
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jun 1, 2009
Project End Date
Sep 30, 2010
Grant Year
(N/A)
Project Director
Pomper, K. W.
Recipient Organization
KENTUCKY STATE UNIVERSITY
(N/A)
FRANKFORT,KY 40601
Performing Department
Agriculture & Environmental Science
Non Technical Summary
Change in knowledge. Pawpaw is in the early stages of domestication. Therefore, understanding the genetic and reproductive mechanisms of pawpaw and maintaining a high level of genetic diversity in future pawpaw cultivars and in breeding material in the KSU Repository would be helpful in continuing the development of a commercial pawpaw industry for farmers in the southeastern United States. Invasive non-native plant species can be devastating to woodland and agricultural ecosystems. Improving our understanding of whether native plants can be used to hold ecological niches or prevent the spread of invasive plant species, would be helpful in developing strategies for invasive plant management. Change in Action. Improving pawpaw germplasm in the repository collection will allow the improvement of culitvars for production by small farmers in the southeastern United States. Establishing native plants such as pawpaw in forest or agricultural areas could assist in preventing the spread of invasive plants and the destruction of current ecosystems. Change in condition. Improved pawpaw cultivars will offer small and limited resource farmers new niche crops to support the economic viability of farmers in the southeastern United States. Since these crops can be grown organically, the organic production of these crops will lead to greater biodiversity, increased beneficial insects, and a reduction in pesticide surface and ground water contamination, contributing positively to a whole system approach to sustainable agriculture. Pawpaw could serve as a local alternative to mango and papaya and therefore reduce energy use and dependence on imported produce. Developing a method to control the spread of invasive plants with native plants, such as pawpaw, will protect native ecosystems.
Animal Health Component
20%
Research Effort Categories
Basic
80%
Applied
20%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2021119108060%
1362300106040%
Goals / Objectives
The pawpaw [Asimina triloba (L.) Dunal] is a native tree-fruit in the early stages of commercial fruit production in Kentucky. Pawpaws also contain Annonaceous acetogenins in the twigs and fruit which have anticancer and antiviral properties with many new product applications. Wild pawpaw patches are usually found in the forest understory and produce many root suckers, presumably forming large clonal patches, thus contributing to poor fruit set within a patch due to flower self-incompatibility. As part of the Kentucky State University (KSU) mission as the USDA National Clonal Germplasm Repository (NCGR) for Pawpaw, assessing genetic diversity displayed in this species, determining the role clonality plays in patch adaption and survival, and collecting unique germplasm for our repository orchards are important research priorities. Native patches serve an important role in the ecosystems around streams and rivers in terms of fruit production for animals, soil erosion control, and enhancing insect biodiversity. The zebra swallowtail butterfly larvae feed exclusively on young pawpaw foliage. Unique native pawpaw germplasm could also serve as future cultivars for growers or be used in KSU breeding efforts. The understory niche occupied by pawpaw may also prevent the establishment of invasive plant species (such as honeysuckle bush). The long-term goals of this project are to understand the cycling and spread of native pawpaw patches as a part of pawpaw germplasm collection efforts of the USDA-NCGR for Pawpaw at KSU, and to identify methods to control the spread of invasive plant species by utilizing selected native plant species (pawpaw). The objectives of this study are to: 1) determine the genetic diversity and clonality displayed in 12 native pawpaw patches (at least 30 trees in each patch) at the Kentucky State University Environmental Education Center (EEC), The Kentucky River, Cove Spring Park in Frankfort, KY, and the Pea Ridge Recreation area that is a part of the Salato Wildlife Education Center in Franklin County using simple sequence repeat DNA marker systems; and 2) determine if pawpaw patches reduce the incidence of invasive species by assessing the occurrence of invasive species (e.g., honeysuckle) within and outside pawpaw patches at the KSU-EEC. The above activities will contribute toward approaches eliminating or preventing the spread of invasive species, and preserving genetic resources of pawpaw and other species for future agricultural uses. Outreach efforts would include guided tours to these sites for the public to describe the importance of enhancing biodiversity in forest ecosystems, a website for the project, and a traveling display/EEC trailer about eliminating or preventing the spread of invasive species and preserving genetic resources of pawpaw and other species for future agricultural uses.
Project Methods
Objective 1. To determine the genetic diversity and clonality of pawpaw patches, leaf samples will be collected along transects through 12 native pawpaw patches (at least 30 trees in each patch) at the KSU Environmental Education Center, along the Kentucky River in Franklin County, Cove Spring Park in Frankfort, KY, and the Pea Ridge Recreation area that is a part of the Salato Wildlife Education Center in Franklin County. The length and width of the patches and the number of stems per patch will be determined. Patches will be photographed and the location of each patch documented by GPS coordinates. DNA will be extracted from the leaves using the DNAMITE Plant Kit in the Core Molecular Genetic Facility on the KSU campus. Four SSR primer sets B3, B103, B129, and G119 will be labeled with FAM and will be used to amplify SSR-PCR products. These products will be separated using a 3130 Applied Biosystems capillary electrophoresis system. Genetic relationships among the pawpaw trees and patches will be examined using the software program Tools For Population Genetic Analysis. Objective 2. To determine if pawpaw patches reduce the incidence of invasive species, the number of invasive species plants within pawpaw patches at the KSU-EEC will be counted and compared to a similar sized adjoining plot next to the pawpaw patch. String grids will be created and invasive plants counted in 5 meter squares in patches and adjoining plots. Invasive plants that will be evaluated will include: bush honeysuckles (Lonicera spp.), periwinkles (Vinca spp.), Royal Paulownia "Princess Tree" (Paulownia tomentosa), Burning Bush (Euonymus alatus), Wintercreeper (Euonymus fortunei), Golden Rain Tree (Koelreuteria paniculata), and other invasive species. The sites will be photographed and the location of each site will be documented by GPS coordinates. In an effort to deliver science-based knowledge to the public, outreach events and products resulting from this project will include research results disseminated by guided tours to collection sites for the public to describe the importance of enhancing biodiversity in forest ecosystems, a presentation at a pawpaw field day, and the creation of a website describing research project progress and results. In order to evaluate the success of the project, mechanisms for self-evaluation and monitoring as well as external evaluation will be implemented to track the project, including monthly progress reports to the KSU administration and weekly group meetings between the P.I., R.A., and student researchers. At these meetings experiments will be planned and results will be discussed, current progress will be assessed and changes made if necessary. Additionally, the defined level of minimum success to document the project's impact will be judged by: a) development of a presentation of research results by the Research Assistant /students involved, and b) the development of two manuscripts will be prepared and submitted to the Journal of the Kentucky Academy of Science, as well as the submission of reports to the Kentucky Nut Growers Association Newsletter: The Kentucky Colonels Kernel and the PawPaw Foundation Newsletter.

Progress 06/01/09 to 09/30/10

Outputs
OUTPUTS: Activities. Leaves from 20 trees were sampled from five pawpaw populations including one population at the Salato Wildlife Center in Frankfort, Ky, three populations at the KSU Environmental Education Center in Henry County, Kentucky, and a Kentucky population of trees grown from seed from trees in Fayette Co., Ky. and DNA extracted using the DNAMITE Plant Kit. Primers B3, B103, and B129 were labeled with FAM and used to amplify PCR-SSR products which were then separated with a 3130 Applied Biosystems capillary electrophoresis system. Genetic relationships were determined using the software program Power Marker. Primers B3, B103, and B129 generated multiple polymorphic alleles at each locus, which ranged from approximately 100 to 350 base pairs in size. Additional pawpaw patches were sampled, from along the Kentucky River, and Cove Spring Park in Frankfort, KY. SSR-PCR analysis indicated that the Kentucky River patch was almost entirely clonal, while the Cove Spring patch had a range of genotypes. The SSR markers generated showed significant genetic variation in the pawpaw populations, indicating these unique populations should be sampled and incorporated into the KSU germplasm collection. Few honeysuckle bushes were found in or around the patches at the EEC, although many bushes were found within a Cove Spring patch. Honeysuckle bushes were only found outside and not within the pawpaw patch along the Kentucky River. Density of the pawpaw patches may impact the ability of honeysuckle to establish within the patches. Events. High school students toured the EEC pawpaw patches. Two high school students completed a project concerning pawpaw DNA finger printing. Services. We answered telephone calls and emails from people who volunteered to send fruit or leaves from wild patches. We mentored high school and undergraduate students in research projects. Products. Pawpaw patch density may impact the ability of honeysuckle bushes to establish within the patches. Pawpaw patch clonality was assessed and will allow the development of sampling approaches for genetic diversity studies in the future. A web site describing the use of DNA fingerprinting with the pawpaw patches at the EEC was developed. Trees containing large fruit were discovered in several wild patches and may serve as a useful source of germplasm for future cultivar development and release. Dissemination. Two KSU undergraduate students gave presentations concerning their research efforts on this project at the Posters-At-The-Capitol meeting in January, 2010. High school students toured the EEC pawpaw patches and learned about the importance of pawpaw in the forest ecosystem. Two undergraduate students presented their research findings the Kentucky Academy of Sciences annual meeting at Northern Kentucky University, in November, 2009. One undergraduate student presented her research on SSR makers in examining genetic diversity of pawpaw in Kentucky for her Senior KSU Biology Seminar. PARTICIPANTS: Individuals. Dr. Kirk Pomper, the project PD, designed experiments, collected samples, assisted in data collection, analyzed data, answered grower questions via email, letters, visits, mentored high school and undergraduate students, wrote and edited abstracts and manuscripts, as well as served as webmaster for a pawpaw website. Mr. Jeremiah Lowe, project Co-Investigator, assisted in designing experiments, collected samples, assisted in data collection, analyzed data, took digital photographs, edited abstracts, and mentored high school and undergraduate students. Partner Organizations: USDA Collaborations: We collaborated with Dr. Kim Hummer (USDA-NCGR, Corvallis, OR) concerning KSU USDA Pawpaw repository efforts in germplasm evaluation. Government Collaborations: Tim Sheehan and the Kentucky Division of Forestry entered into an agreement with KSU to obtain high-quality pawpaw seed and to sell seedlings to the public. We collaborated with the City of Frankfort, Kentucky, in sampling and evaluating the pawpaw patch at Cove Spring Park in Frankfort, Kentucky. Grower Collaborations: We have collaborative research relationships with pawpaw growers: Ken Waters (Shelby Co., KY), Larry Daulton (Nicholasville, KY), and Mark Hilderbrand (Fairbanks, IN). The growers have native pawpaw patches on their farms for DNA sampling. Collaborators and contacts: KSU Collaborators. We have research collaborations with Drs. Li Lu, James Tidwell, and Boris Gomelsky in molecular genetics in methodologies with germplasm. Training or professional development. Two high school and two undergraduate students completed research projects using DNA markers to determine if pawpaw patches were clonal. TARGET AUDIENCES: Target audiences. The needs of small family farms and limited resource farmers in Kentucky and the southeastern United States were addressed by this project by obtaining new genetic resources for pawpaw that will aid in developing this new niche crop for production in these regions. This project also impacts entrepreneurs, farmers markets, and other specialty fruit retailers. Kentucky and the southeast U.S. are continuing to make a transition from tobacco to new crops; therefore, pawpaw production could provide a high value crop for this region. This project could therefore significantly impact low-income minority farmers by providing new crop and market opportunities for these individuals. Efforts. High school students in the Research and Extension Apprenticeship Program toured the EEC pawpaw patches and learned about the importance of pawpaw in the forest ecosystem. A high school student conducted a research project and presented her work on DNA finger printing of patches and genetic diversity to about 75 students and their families. An article was written and published in the Kentucky Nut Growers Association Newsletter concerning the project and our interest in identifying future pawpaw patches for research on genetic diversity. A web site describing the use of DNA fingerprinting with the pawpaw patches at the EEC was developed and placed on the KSU Pawpaw Website at http://www.pawpaw.kysu.edu/Mcintire-StennisPawpawPatch.htm. PROJECT MODIFICATIONS: None.

Impacts
Change in knowledge. The North American pawpaw is a tree fruit native to eastern North America which is in the early stages of domestication Therefore, understanding the genetic and reproductive mechanisms of pawpaw and maintaining a high level of genetic diversity in future pawpaw cultivars and in breeding material in the KSU Repository would be helpful in continuing the development of a commercial pawpaw industry for farmers in the southeastern United States. Invasive non-native plant species can be devastating to woodland and agricultural ecosystems. A better understanding of whether native plants can be used to hold ecological niches or prevent the spread of invasive plant species would be helpful in developing strategies for invasive plant management. Change in Action. Enhancing pawpaw germplasm diversity in the repository collection will allow for the improvement of cultivars for production by small farmers in the southeastern United States. Establishing native plants such as pawpaw in forest or agricultural areas could assist in preventing the spread of invasive plants and the destruction of current ecosystems. Change in condition. Improved pawpaw varieties will offer small and limited resource farmers new niche crops to support the economic viability of farmers in Kentucky and the southeastern United States. Since these crops can be grown organically, the organic production of these crops will lead to greater biodiversity, increased beneficial insects, and a reduction in pesticide contamination of surface and ground water, contributing positively to a whole system approach to sustainable agriculture. Pawpaw could serve as a local alternative to mango and papaya and therefore reduce energy use and dependence on imported produce. Developing a method to control the spread of invasive plants with native plants, such as pawpaw, will protect native ecosystems.

Publications

  • Bowie, LaQuida, Li Lu, Kirk Pomper, Jeremiah Lowe, Sheri Crabtree, and William Stilwell. 2010. Evaluation of Genetic Variation Among Native Pawpaw Patches in Henry County, Kentucky. Ninth Annual Posters-At-The-Capitol Meeting Abstract Book. Page 21. http://campus.murraystate.edu/services/URSA.
  • Durham, Jessica, Li Lu, Kirk Pomper, Jeremiah Lowe, and Sheri Crabtree. 2010. Using DNA Markers to Evaluate Genetic Diversity Among Native Pawpaw Patches in Iowa and Kentucky. Ninth Annual Posters-At-The-Capitol Meeting Abstract Book. Page 34. http://campus.murraystate.edu/services/URSA.


Progress 06/01/09 to 09/30/09

Outputs
OUTPUTS: Activities. Leaves were sampled from pawpaw patches at the KSU Environmental Education Center (EEC) in Henry County, Kentucky. DNA was extracted using the DNAMITE Plant Kit from leaf samples collected from 20 trees per patch on a transect line in three native patches at the EEC. Patch 1 was located on a hill, while patches 2 (downstream) and 3 (upstream) were located on a stream about 100 feet apart. GPS coordinates and digital photos were recorded for each patch. Primers B3, B103, B129, C104, and G119 were used to amplify SSR products and products were separated with a 3130 Applied Biosystems capillary electrophoresis system. All three patches were genetically distinct, with patches 2 and 3 being more similar. Patch 3 was clonal with only one genotype. The high genetic variation in patch 2 supports involvement of water transport of seed from patch 3 in the establishment of the patch; however, animal transport of seed could also have led to patch establishment. Additional pawpaw patches were sampled, from along the Kentucky River, and Cove Spring Park in Frankfort, KY. SSR-PCR analysis indicated that the Kentucky River patch was almost entirely clonal, while the Cove Spring patch had a range of genotypes. No honeysuckle bushes were found in or around the patches at the EEC. Honeysuckle bushes were present within and outside of the Cove Spring pawpaw patch; however, honeysuckle bushes were only found outside and not within the pawpaw patch along the Kentucky River. Density of the pawpaw patches may impact the ability of honeysuckle to establish within the patches. Events. High school students in the Research and Extension Apprenticeship Program toured the EEC pawpaw patches. A high school student completed a project concerning DNA finger printing of patches and made a presentation at the KSU Research and Extension Apprenticeship Program Final Program. Services. We answered telephone calls and emails from people who volunteered to send fruit or leaves from wild patches. We mentored a high school and an undergraduate student in research projects. Products. Pawpaw patch density may impact the ability of honeysuckle to establish within the patches. Pawpaw patch clonality was assessed and will allow the development of sampling approaches for genetic diversity studies. A web site describing the use of DNA fingerprinting with the pawpaw patches at the EEC was developed and placed on the KSU Pawpaw Website at http://www.pawpaw.kysu.edu/Mcintire-StennisPawpawPatch.htm. Trees containing large fruit were discovered in a patch at Cove Spring Park and may serve as a useful source of germplasm for future cultivar development and release. Dissemination. High school students in the Research and Extension Apprenticeship Program toured the EEC pawpaw patches and learned about the importance of pawpaw in the forest ecosystem. A high school student presented her work on DNA finger printing of patches and genetic diversity to about 75 students and their families. An article was written and published in the Kentucky Nut Growers Association Newsletter concerning the project and our interest in identifying future pawpaw patches for research on genetic diversity. PARTICIPANTS: Individuals. Dr. Kirk Pomper, the project PD, designed experiments, collected samples, assisted in data collection, analyzed data, answered grower questions via email, letters, visits, mentored high school and undergraduate students, wrote and edited abstracts and manuscripts, as well as served as webmaster for a pawpaw website. Mr. Jeremiah Lowe, project Co-Investigator, assisted in designing experiments, collected samples, assisted in data collection, analyzed data, took digital photographs, edited abstracts, and mentored high school and undergraduate students. Partner Organizations: USDA Collaborations: We collaborated with Dr. Kim Hummer (USDA-NCGR, Corvallis, OR) concerning KSU USDA Pawpaw repository efforts in germplasm evaluation. Government Collaborations: We collaborated with the City of Frankfort, Kentucky, in sampling and evaluating the pawpaw patch at Cove Spring Park in Frankfort, Kentucky. Grower Collaborations: We have collaborative research relationships with pawpaw growers: Ken Waters (Shelby Co., KY), Larry Daulton (Nicholasville, KY), and Mark Hilderbrand (Fairbanks, IN). The growers have native pawpaw patches on their farms for DNA sampling. Collaborators and contacts: KSU Collaborators. We have research collaborations with Drs. Li Lu, James Tidwell, and Boris Gomelsky in molecular genetics in methodologies with germplasm. Training or professional development. One high school and one undergraduate student completed research projects using DNA markers to determine if pawpaw patches were clonal. TARGET AUDIENCES: Target audiences. The needs of small family farms and limited resource farmers in Kentucky and the southeastern United States were addressed by this project by obtaining new genetic resources for pawpaw that will aid in developing this new niche crop for production in these regions. This project also impacts entrepreneurs, farmers markets, and other specialty fruit retailers. Kentucky and the southeast U.S. are continuing to make a transition from tobacco to new crops; therefore, pawpaw production could provide a high value crop for this region. This project could therefore significantly impact low-income minority farmers by providing new crop and market opportunities for these individuals. Efforts. High school students in the Research and Extension Apprenticeship Program toured the EEC pawpaw patches and learned about the importance of pawpaw in the forest ecosystem. A high school student conducted a research project and presented her work on DNA finger printing of patches and genetic diversity to about 75 students and their families. An article was written and published in the Kentucky Nut Growers Association Newsletter concerning the project and our interest in identifying future pawpaw patches for research on genetic diversity. A web site describing the use of DNA fingerprinting with the pawpaw patches at the EEC was developed and placed on the KSU Pawpaw Website at http://www.pawpaw.kysu.edu/Mcintire-StennisPawpawPatch.htm. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Change in knowledge. Pawpaw is in the early stages of domestication. Therefore, understanding the genetic and reproductive mechanisms of pawpaw and maintaining a high level of genetic diversity in future pawpaw cultivars and in breeding material in the KSU Repository would be helpful in continuing the development of a commercial pawpaw industry for farmers in the southeastern United States. Invasive non-native plant species can be devastating to woodland and agricultural ecosystems. Improving our understanding of whether native plants can be used to hold ecological niches or prevent the spread of invasive plant species would be helpful in developing strategies for invasive plant management. Change in Action. Improving pawpaw germplasm in the repository collection will allow for the improvement of cultivars for production by small farmers in the southeastern United States. Establishing native plants such as pawpaw in forest or agricultural areas could assist in preventing the spread of invasive plants and the destruction of current ecosystems. Change in condition. Improved pawpaw cultivars will offer small and limited resource farmers new niche crops to support the economic viability of farmers in the southeastern United States. Since these crops can be grown organically, the organic production of these crops will lead to greater biodiversity, increased beneficial insects, and a reduction in pesticide contamination of surface and ground water, contributing positively to a whole system approach to sustainable agriculture. Pawpaw could serve as a local alternative to mango and papaya and therefore reduce energy use and dependence on imported produce. Developing a method to control the spread of invasive plants with native plants, such as pawpaw, will protect native ecosystems.

Publications

  • Pomper, K. W. 2009. Pawpaw Patch Research at Kentucky State University-We Need Your Help! The Kentucky Colonels Kernel 2-39 (3):4.