Articles
ESTABLISHMENT OF A TRANSFORMATION SYSTEM FOR PRECOCIOUS TRIFOLIATE ORANGE AND MOLECULAR BREEDING FOR POTENTIAL SEEDLESSNESS IN CITRUS
Article number
892_11
Pages
95 – 99
Language
English
Abstract
A transformation system for precocious trifoliate orange (Poncirus trifoliate) was established.
First, a GFP gene was introduced by using etiolated stem segments as explants.
One hundred three transgenic lines were obtained, and the transgene was integrated into plant genome with 1 to 3 copies.
Expression levels of the GFP gene in transgenic lines did not correlate with its copy number as revealed by Real-time RT-PCR analysis.
Twenty-five well-developed transgenic plants were regenerated and transferred to the soil.
After 18 months, 15 of these plants flowered and then 6 set fruits.
GFP expression was stable in flowers, fruits and seeds of transgenic lines as well as in the germinated seedlings.
Second, the function of Arabidopsis thaliana MAC12.2 (KNU) gene was tested by using the above established transformation system.
Among the 38 well-developed transgenic plants, 32 flowered 15 months after transfer to the soil and 11 set fruits.
Five transgenic lines set fruits with significantly fewer seeds than the controls.
The above results suggested precocious trifoliate orange could be a good model genotype for functional genomics studies in Citrus. Third, transgenic plants of seedy cultivars containing CG1-400-RNase gene with potential to induce seedless fruits were regenerated and characterized.
Transformations of epicotyl segments were performed in four genotypes, i.e. Murcott tangor, Jincheng, Hongjiang and Taoye sweet oranges.
Transformation efficiency for Murcott was 0.93% and 5 transgenic plants were identified, among which three PCR positive plants have two copies of the CG1-400-RNase gene.
For Jincheng orange, 11 transgenic plants were obtained, eight of which were confirmed as transformants by repetitive PCR analysis, and have a single copy of CG1-400-RNase gene by Southern blot analysis.
Three transgenic plants of Hongjiang and one transgenic plant of Taoye were obtained as revealed by PCR analysis.
First, a GFP gene was introduced by using etiolated stem segments as explants.
One hundred three transgenic lines were obtained, and the transgene was integrated into plant genome with 1 to 3 copies.
Expression levels of the GFP gene in transgenic lines did not correlate with its copy number as revealed by Real-time RT-PCR analysis.
Twenty-five well-developed transgenic plants were regenerated and transferred to the soil.
After 18 months, 15 of these plants flowered and then 6 set fruits.
GFP expression was stable in flowers, fruits and seeds of transgenic lines as well as in the germinated seedlings.
Second, the function of Arabidopsis thaliana MAC12.2 (KNU) gene was tested by using the above established transformation system.
Among the 38 well-developed transgenic plants, 32 flowered 15 months after transfer to the soil and 11 set fruits.
Five transgenic lines set fruits with significantly fewer seeds than the controls.
The above results suggested precocious trifoliate orange could be a good model genotype for functional genomics studies in Citrus. Third, transgenic plants of seedy cultivars containing CG1-400-RNase gene with potential to induce seedless fruits were regenerated and characterized.
Transformations of epicotyl segments were performed in four genotypes, i.e. Murcott tangor, Jincheng, Hongjiang and Taoye sweet oranges.
Transformation efficiency for Murcott was 0.93% and 5 transgenic plants were identified, among which three PCR positive plants have two copies of the CG1-400-RNase gene.
For Jincheng orange, 11 transgenic plants were obtained, eight of which were confirmed as transformants by repetitive PCR analysis, and have a single copy of CG1-400-RNase gene by Southern blot analysis.
Three transgenic plants of Hongjiang and one transgenic plant of Taoye were obtained as revealed by PCR analysis.
Authors
B. Tan, W.W. Guo
Keywords
citrus, seedless breeding, precocious trifoliate orange, ‘Murcott’ tangor, transformation efficiency
Online Articles (48)