DROUGHT-TOLERANT TRANSGENIC PERENNIAL RYEGRASS (LOLIUM PERENNE L.) OBTAINED VIA PARTICLE BOMBARDMENT GENE TRANSFORMATION OF CBF3/DREB1A GENE
Embryogenic calluses, initiated from mature embryos of three cultivars were transformed with pCAMBIA1301 containing -glucuronidase (GUS) gene, hygromycin phosphstransferase (HPT) gene, and the Arabidopsis CBF3/DREB1A gene by bombardment. To screen the putative transgenic plants, subsequent selection in the presence of a high concentration of hygromycin was applied at the tissue culture stage (100 mg L-1) and in the regeneration medium (50 mg L-1). In hygromycin-tolerant plants, genomic integration of CBF3 was confirmed by PCR amplification followed by Southern and Northern analyses. All the transgenic plants grew, and developed into sexual stage naturally under the greenhouse and field conditions. Transgenic and control plants of two cultivars were exposed to drought stress in greenhouse until they became brown and completely desiccated (16 d). Transgenic plants from two cultivars both exhibited lower electrolyte leakage (EL), malondialdehyde (MDA), and peroxidase (POD) activity than did control plants along with the decline of the soil moisture content (SMC). The chlorophyll content and superoxide dismutase (SOD) activities in transgenic plants were higher than that in control plants when the SMC declined. The adverse impact of the drought stress was more severe for control plants than for transgenic plants. CBF3/DREB1A transgenic ryegrass with enhanced drought tolerance suggested that the overexpression of the CBF3 gene serves as a novel strategy to produce drought-tolerant grasses.
Liebao, H., Xue Li, , Jun Liu, and Huiming Zeng, (2008). DROUGHT-TOLERANT TRANSGENIC PERENNIAL RYEGRASS (LOLIUM PERENNE L.) OBTAINED VIA PARTICLE BOMBARDMENT GENE TRANSFORMATION OF CBF3/DREB1A GENE. Acta Hortic. 783, 273-282
turfgrass, embryogenic callus, drought tolerance, bombardment, gene transfer