Grant Information
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|---|---|---|
| 202 - Plant Genetic Resources | 1050 - Date | 1080 - Genetics (excludes breeding) | 20% |
| 202 - Plant Genetic Resources | 910 - Grapefruit | 1080 - Genetics (excludes breeding) | 20% |
| 202 - Plant Genetic Resources | 920 - Orange | 1080 - Genetics (excludes breeding) | 20% |
| 202 - Plant Genetic Resources | 930 - Lemon | 1080 - Genetics (excludes breeding) | 20% |
| 202 - Plant Genetic Resources | 999 - Citrus, general/other | 1080 - Genetics (excludes breeding) | 20% |
ARS scientists have developed the protocol for cryopreserve citrus (ms submitted) and had preliminary evidence that the methodology may be applied to several varieties of citrus. Scientists will develop the protocols used for cryotherapy. The citrus breeding team at USHRL, Ft. Pierce, will maintain plants under protected conditions in Florida and assist with biological indexing and extraction of nucleic acids for use for laboratory detections. ARS scientists will perform laboratory diagnostics establish biological indexing trials at the USHRL, Ft. Pierce using young indicator seedlings. Milestones distributed over the two years will be: 1) Develop cryotherapy protocols for mandarins, sweet oranges. Apply cryotherapy protocols to citrus germplasm collected as part of the germplasm recovery project and held in under protected conditions at USHRL, Ft. Pierce. Conduct biological and lab diagnostic assays to accessions before and after cryotherapy to determine effectiveness of pathogen removal. 2) Develop cryotherapy protocols for grapefruit and pummelos. Apply to germplasm held at Ft. Pierce as well as from collections made from trees in the field. Conduct biological and lab diagnostic assays to accessions before and after cryotherapy to determine effectiveness of pathogen removal. 3) Develop cryotherapy protocols for lemons, limes, papeda and citrus relatives. Apply to germplasm held at Ft. Pierce as well as from collections made from trees in the field. Conduct biological and lab diagnostic assays to accessions before and after cryotherapy to determine effectiveness of pathogen removal.
This project is related to objective 1, Develop and apply new methods for conserving and propagating citrus and date genetic resources which improve genebank operating efficiency and effectiveness and which enable pathogen-tested materials and associated information to be distributed worldwide", of the parent project. The purpose of this project is to determine methods to effectively eliminate �Candidatus Liberibacter asiaticus� (Las), the bacterium associated with huanglongbing (HLB) in Florida from citrus which are used as budwood sources. Emphasis is being placed on cryotherapy as well as other treatments which may be successful at elimation of Las, such as antibiotic treatments and heat treatments. Accessions of tangelo, grapefruit, mandarin and pummelo have been forwarded to the Plant Germplasm Preservation Research Unit, Ft. Collins, Colarado, for treatment using cryotherapy. The recovered plants are being tested for presence of Las at intervals following treatment.