Page 157 - 《广西植物》2025年第7期
P. 157
7 期 蒋琼海等: 秋石斛遗传转化筛选标记基因及筛选剂的筛选 1 3 4 9
Abstract: Phalaenopsis ̄type Dendrobium hybrids (Den ̄Phals) are important ornamental plants in tropical areasꎬ with
unique flower shapes and rich colorsꎬ and have extremely high industrial value in flower market. Molecular breeding is an
important means to break through the limitations of traditional breedingꎬ and screening marker genes assisted transformation
can accelerate transgenic process. In order to obtain suitable selection marker genes and agents for genetic transformation of
Den ̄Phalsꎬ the study took the embryogenic calluses ( ECs) and protocorms of Dendrobium ‘ Sonia Hiasakul’ and
Dendrobium ‘Nobile Lindl.’ as explantsꎬ and placed them on media containing different concentrations of kanamycinꎬ
geneticin (G418)ꎬ hygromycin and bialaphos to test the sensitivity of two varieties to different screening agentsꎬ observe
their growth statusꎬ and calculate survival rates. Furthermoreꎬ conducted genetic transformation test using the optimal
screening marker gene and screening agent. The results were as follows: (1) The explants of the two varieties had consistent
sensitivity to different screening agentsꎬ that isꎬ they were relatively sensitive to hygromycinꎬ G418ꎬ bialaphosꎬ but
 ̄1
insensitive to kanamycin and could still growth normally in the culture medium with a concentration of 700 mgL .
 ̄1
(2) The lethal concentrations of hygromycinꎬ G418 and bialaphos to explants were 30ꎬ 50ꎬ 7 mgL ꎬ respectively.
(3) Using hygromycin as the screening agent and hpt as the screening marker geneꎬ the initial screening concentration of 30
 ̄1
mgL was optimalꎬ with the screening cycle extendedꎬ increasing the concentration of the screening agent was beneficial
for obtaining transgenic lines. The study has determined the sensitivity and minimum lethal concentrations of two varieties of
Den ̄Phals to different screening agentsꎻ hptꎬ nptꎬ and bar can all be used as screening marker genes for establishment of
genetic transformation systems of Den ̄Phalsꎬ with corresponding screening agents are hygromycinꎬ G418ꎬ and bialaphosꎬ
respectively. In additionꎬ during genetic transformation screening processꎬ increasing the concentration gradient of the
screening agent is beneficial for obtaining transgenic explants.
Key words: Phalaenopsis ̄type Dendrobium hybridsꎬ selection marker geneꎬ screening agentꎬ genetic transformationꎬ
selection concentration
秋 石 斛 ( Phalaenopsis ̄type Dendrobium hybridsꎬ 体系之前ꎬ有必要对不同筛选剂进行敏感性测试ꎮ
Den ̄Phals ) 是 兰 科 第 二 大 属———石 斛 属 石斛兰遗传转化研究中常用的筛选标记基因有新
(Dendrobium)中观赏性极高的盆栽与切花兼用型花 霉素磷酸转移酶基因( npt)、潮霉素磷酸转移酶基
卉ꎮ 其商业化品种选育主要依赖于传统育种ꎬ受资 因(hpt)和草丁膦乙酰转移酶基因( bar) ( Knapp et
源遗传背景限制ꎬ难以获得较大突破ꎬ如花色、花 al.ꎬ 2000ꎻChai et al.ꎬ 2007)ꎮ npt 赋予转基因植物
香、花型、抗逆、抗寒定向改良(Kishi ̄Kaboshi et al.ꎬ 多种氨基糖苷类抗生素抗性ꎬ如卡那霉素、新霉素
2018)ꎮ 相比之下ꎬ利用分子育种技术不仅可以加 和 G418(Ovcharenko & Rudasꎬ 2023)ꎬ其中卡那霉
速新种质创制ꎬ 还可以实现精准育种 ( Xu et al.ꎬ 素是石斛兰遗传转化对应 npt 基因最常用的筛选
2019ꎻZhang et al.ꎬ 2022ꎻLi Y et al.ꎬ 2022)ꎮ 石斛兰 剂(da Silva et al.ꎬ 2016a)ꎮ 然而ꎬ兰科植物对卡
转基因研究虽然已经有几十年历史ꎬ但转化周期 那霉素具有天然的抗性ꎬ需要较高的剂量才能获
长、转化效率低、转基因植株嵌合率高仍是限制该 得转基因株系ꎮ 虽然卡那霉素相较于其他筛选剂
技术广泛应用的主要因素(da Silva et al.ꎬ 2016aꎻ 成本较低ꎬ但其筛选过程更容易获得嵌合体ꎬ不仅
Ovcharenko & Rudasꎬ 2023)ꎮ 目前ꎬ我国石斛兰分 耗时且费力( Chai et al.ꎬ 2007)ꎮ hpt 是石斛兰遗
子育种研究主要集中在药用铁皮石斛、流苏石斛 传转化研究中应用最多的筛选标记基因ꎬ因为石
和金钗石斛ꎬ尚未见到关于秋石斛分子育种的报 斛兰对潮霉素敏感ꎬ低浓度即可以完全抑制非转
道(Men et al.ꎬ 2003ꎻ崔波等ꎬ2015ꎻ黄超群等ꎬ2018)ꎮ 化株系的生长ꎬ所以该筛选剂除了贵并没有太大缺
在遗传转化研究中应用筛选标记基因或报告 点(da Silva et al.ꎬ 2016a)ꎮ bar 基因编码草丁膦乙
基因辅助筛选可以显著地提高转化效率和节约时 酰转移酶ꎬ对草铵膦和双丙氨膦均具有抗性ꎬ转化
间成本ꎮ 石斛兰已报道的品种超过 1 500 个ꎬ不同 该基因不仅可以实现转化植株的抗性筛选ꎬ还可以
基因型对 筛 选 剂 的 敏 感 性 存 在 差 异 ( da Silva et 赋予转基因植株除草剂抗性ꎬ因此在石斛兰中也有
al.ꎬ 2016aꎬ b)ꎮ 因此ꎬ在构建本地品种遗传转化 应用报道(Chai et al.ꎬ 2007ꎻDing et al.ꎬ 2013)ꎮ

