식물조직배양 및 형질전환기술을 이용한 신품종 잔디의 개발

Abstract

GSDL1, an AT-hook DNA binding family protein gene from Arabidopsis, is known to play a role in abiotic stress such as drought. In this study, transgenic zoysiagrass plants containing GSDL1 gene were produced by Agrobacterium-mediated transformation to develop stress-tolerant variety of turfgrass. After transformation, putative transgenic plants were screened using Trait LL Test Strips which detects PAT protein. Integration of the GSDL1 gene into the transgenic plants was confirmed by genomic PCR and Southern blot analysis and the expression of GSDL1 gene was confirmed by RT-PCR. The transgenic zoysiagrass plants overexpressing GSDL1 gene showed significantly enhanced drought tolerance and also showed delaying post-harvest senescence compared to wild type zoysiagrass. Kentucky bluegrass is a typical cool-season perennial grass with apomictic reproduction and is mainly used in playing fields. Due to the apomictic mode of reproduction, development of new varieties of this species by conventional breeding is very difficult. Therefore, genetic transformation can be a good alternative method for introducing desirable traits and new genes into kentucky bluegrass. The purpose of this study was to establish an efficient plant regeneration system from seed-derived callus cultures of kentucky bluegrass for genetic transformation. Plant regeneration from seed-derived callus cultures of five kentucky bluegrass cultivars was tested on MS basal medium supplemented with different growth regulators. MS medium containing 1mg/L 2,4-D, 1mg/L BA was optimal for shoot-forming callus (type 1) induction. The highest frequency of type 1 callus induction (22.7%) and plant regeneration (98.8%) was obtained from 'Midnight'. In this study, we established a highly efficient regeneration system for kentucky bluegrass. The established protocol could be a powerful tool for molecular breeding of kentucky bluegrass through genetic transformation.