In vitro propagation of Cyrtopodium saintlegerianum rchb. f. (orchidaceae), a native orchid of the Brazilian savannah

In order to enable production of large quantities of plantlets for reintroduction programs, as well as economic exploration, Cyrtopodium saintlegerianum seeds were sown on Knudson culture medium. After seed germination, the protocorms were inoculated on Knudson culture medium supplemented with 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA). The obtained shoots were individually inoculated in Knudson supplemented with gibberellic acid (GA3) in order to promote elongation. Seedlings were evaluated and then transplanted into trays containing commercial substrate Plantmax(r)-HT, or crushed Acuri leaf sheath. Auxin/cytokinin ratio influenced in vitro propagation of C. saintlegerianum, resulting in increased shoot number when 2.0 mg L-1 BA was added to the culture medium in the absence or presence of 0.5 mg L-1 NAA. This species proved to be promising for massal in vitro multiplication. Despite having incremented in vitro shoots elongation, the use of GA3 is unnecessary since it contributed negatively in the acclimatization of plants.

为满足回归引种计划的大规模组培苗生产需求，同时兼顾经济开发价值，研究人员将圣莱热兰（Cyrtopodium saintlegerianum）的种子播种于Knudson培养基（Knudson culture medium）中。种子萌发后，将原球茎接种于添加了6-苄基腺嘌呤（6-benzyladenine，BA）与α-萘乙酸（α-naphthaleneacetic acid，NAA）的Knudson培养基上。将获得的不定芽单独接种于添加赤霉素（gibberellic acid，GA3）的Knudson培养基中，以促进芽体伸长。对组培幼苗进行性状评估后，将其移栽至含有Plantmax®-HT商品基质或粉碎Acuri叶鞘的育苗盘中。生长素与细胞分裂素的配比显著影响圣莱热兰的离体繁殖效率：当培养基中添加2.0 mg·L⁻¹ BA，且添加或不添加0.5 mg·L⁻¹ NAA时，不定芽数量可显著提升。该物种具备大规模离体扩繁的应用潜力。尽管赤霉素可促进离体芽体伸长，但会对植株的驯化移栽产生负面影响，因此无需使用赤霉素。