Source: UNIV OF HAWAII submitted to
TRANSGENIC AND CONVENTIONAL APPROACHES TO STRENGTHEN THE PAPAYA AND CITRUS INDUSTRIES IN HAWAII
 
PROJECT DIRECTOR: Ferreira, S. A.
 
PERFORMING ORGANIZATION
Plant & Environmental Protection Sciences
UNIV OF HAWAII
HONOLULU,HI 96822
 
NON TECHNICAL SUMMARY: This project uses molecular and conventional breeding methods to develop broader transgenic PRSV-resistance in papaya and to confirm the transgenic approach for CTV-resistance in citrus. Both of these viruses seriously constrain production in papaya and citrus. Broader resistance to PRSV removes the threat of foreign or new strains that would threaten survival. Broader PRSV resistance would also be useful in other papaya growing areas of the world, and the use of this technology could benefit growers beyond Hawaii. With citrus, CTV resistance would provide an opportunity for Hawaii to resurrect commercial citrus production in Hawaii. Further, because of the diverse nature of the CTV population in Hawaii (probably due to the long association of CTV and its aphid vector), CTAHR could become the world center for CTV screening for breeders around the world for both transgenic and conventional citrus lines. For this to happen, proof of concept is needed, and is one of the basic goals of this project. This project offers the opportunity to integrate the basic research with extension activities supporting the transfer and practical utilization of the research. In the case of papaya, completing the deregulation process for Rainbow and SunUp in Japan is critical to assuring Hawaii's most important market niche in Japan. In addition, given the heightened level of activism opposing GM technology, using the success of transgenic papaya as a spring board for discussions with targeted clients should be very useful in assisting with acceptance of GM. Finally, CTAHR has not released a new papaya variety since 1977. Part of the proposed research and extension efforts will center on evaluating and releasing a new solo papaya with a distinct taste and color profile from the two important export varieties, Kapoho and Sunrise.
 
OBJECTIVES: Research Goals are: 1. Broaden the level of Papaya Ringspot Virus (PRSV) transgenic resistance in papaya to decrease the threat of foreign or alien strains of PRSV. 2. Integrate other transgenic traits in papaya to improve fruit shelf life and to delay fruit softening for resistance to postharvest diseases. 3. Develop a field testing site and protocols for evaluating Citrus Tristeza Virus (CTV) transgenic resistance in citrus for Mexican lime lines developed in Spain and in Hawaii, and other transgenic citrus lines developed in California. Extension Goals are: 1. Work with the team of GONSALVES to complete the deregulation of SunUp and Rainbow transgenic papaya varieties in Japan. 2. Conduct a GMO educational program utilizing the transgenic papaya example to discuss various issues and aspects of issues raised by activists opposing acceptance of GMO technology, targeting important decision makers in the community and in different industry groups. 3. Conduct late stage field trials to evaluate a new papaya variety for Hawaii and potentially elsewhere, with a new and improved flavor profile, and attractive flesh color distinct from Sunrise and Kapoho. Outputs: 1. Activities will culminate in development and release of new transgenic papayas for use in Hawaii and around the world, 2. a more general understanding and acceptance of GMO technology in agricultural applications. 3. Resurrect the lime industry in Hawaii. 4. Share research and extension information at field days and at scientific meetings.
 
APPROACH: Research: 1. To develop broadly resistant transgenic papayas, Kapoho (Kp) and Sunrise (Sr) will be transformed with the CP gene segments of PRSV from Thailand, Taiwan, and Keaau, HI. Transgenic plants will be evaluated for resistance to the Hawaii strain of PRSV both in the greenhouse and field. Selections will be made for horticultural characteristics and for broad virus resistance. Note that all field work must be conducted with necessary biotech release permits from APHIS/BRS. 2. Papaya lines of Kp and Sr transformed with both PRSV CP gene and with 3 isozymes of beta-galactosidase genes originally obtained from papaya (this should result in resistant transgenic lines with down-regulated fruit softening gene expression) to develop new varieties with extended shelf-life. Deregulate these enhanced transgenic papaya lines. 3. In a field trial, evaluate transgenic citrus lines for resistance to CTV. Characterize selected lines molecularly to confirm presence of transgenes and to determine gene expression levels in selected lines. Mexican lime transformants from Spain and Hawaii, and sweet orange transformants from California will be evaluated for CTV resistance.
 
CRIS NUMBER: 0217250 SUBFILE: CRIS
PROJECT NUMBER: HAW00975-H SPONSOR AGENCY: NIFA
PROJECT TYPE: HATCH PROJECT STATUS: NEW MULTI-STATE PROJECT NUMBER: (N/A)
START DATE: Jan 15, 2008 TERMINATION DATE: Sep 30, 2011

GRANT PROGRAM: (N/A)
GRANT PROGRAM AREA: (N/A)

CLASSIFICATION
Knowledge Area (KA)Subject (S)Science (F)Objective (G)Percent
201099911012.210%
201103011012.240%
212099911014.210%
212103011014.240%

CLASSIFICATION HEADINGS
KA201 - Plant Genome, Genetics, and Genetic Mechanisms
KA212 - Pathogens and Nematodes Affecting Plants
S1030 - Papaya
S0999 - Citrus, general/other
F1101 - Virology
G2.2 - Increase Efficiency of Production and Marketing Systems
G4.2 - Reduce Number and Severity of Pest and Disease Outbreaks


RESEARCH EFFORT CATEGORIES
BASIC 30%
APPLIED 40%
DEVELOPMENTAL 30%

KEYWORDS: papaya~transgenic~prsv~resistance~virus-resistance~citrus~ctv~extension~education

PROGRESS: TO
(N/A)

IMPACT: TO (N/A)

PUBLICATION INFORMATION: TO


PROJECT CONTACT INFORMATION
NAME: Ferreira, S. A.
PHONE: 808-956-7854
FAX: 808-956-2832