Sponsoring Institution
Agricultural Research Service/USDA
Status
ACTIVE
Funding Source
USDA INHOUSE
Reporting Frequency
Annual
Project Director
MCCOLLUM T G
Accession Number
427843
Project Number
6034-21000-016-05R
Dates
2014-07-01 - 2016-08-31
Recipient Organization
AGRICULTURAL RESEARCH SERVICE
219 SOUTH ROCK ROAD
FT PIERCE,FL 34945
Keywords
antibiotic
asiaticus
biological
candidatus
indexing
liberibacter
pathogen-free
therapy
Research Effort
Applied (30%)
Basic (70%)
Developmental (0%)
Classification Parameters
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|
| 203 - Plant Biological Efficiency and Abiotic Stresses Affecting Plants |
920 - Orange |
1000 - Biochemistry and biophysics |
50% |
| 204 - Plant Product Quality and Utility (Preharvest) |
999 - Citrus, general/other |
1080 - Genetics (excludes breeding) |
50% |
Goals / Objectives
The purpose of this project is to apply the new technologies of cryotherapy and the use of "mini-plant-indexing" to accelerate the cleaning of germplasm accessions for use in citrus breeding in Florida. Transformation trials from field evaluation trials would also benefit. From ongoing projects, we have been able to demonstrate the effectiveness of cryotherapy to eliminate HLB, also citrus viroids and Citrus tatterleaf virus (pathogens which are the most difficult to eliminate using traditional shoot tip grafting). We have also demonstrated the effectiveness of using very young seedling indicators to obtain biological index information within 5 months of sowing the seed ("mini-plant-indexing"), obtaining the same results as using traditional biological indexing requiring 12-14 months after seed sowing. This is a request for funds for technical support to clean priority materials in the Florida breeding program, and to clean prioritized germplasm for Florida that are present in California.
Methods (unparsed)
Year 1: At each location, Florida, California, and Colorado, 30 accessions will be cleaned with cryotherapy. Following recovery from the cryotherapy, plants are grown in vitro on seedling rootstocks for 15 weeks before testing using laboratory based diagnostics for HLB and other graft transmissible pathogens. In vitro clones testing negative will be established in quarantine in Florida and California; in Colorado they will be forwarded under permit to California for establishment. Once the recovered plant has grown to sufficient size, testing will be done as required for release from quarantine in Florida or in California. Young indicator plants will be utilized for biological indexing. We anticipate at least 45 accessions being therapied, indexed and released from quarantine by the end of year 1, with additional accessions in the stream for release early in yr 2. Year 2: At each of the three locations, an additional 45 accessions will be cleaned with cryotherapy, and subsequently indexed by laboratory and biological indexing methods for release.