猴面包树的离体快繁条件筛选

Screening for in vitro rapid propagation conditions of Adansonia digitata

关键词:  猴面包树, 种子萌发, 离体培养, 快速繁殖

Key words:  Adansonia digitata, seed germination, in vitro culture, rapid propagation

摘要:

该文以猴面包树(Adansonia digitata)种子为外植体,首先筛选合适的种子预处理及消毒方法,然后经过启动培养获得无菌外植体后在增殖培养基中进行丛生芽诱导,将丛生芽切成单株进行生根壮苗培养,最终建立猴面包树离体快繁技术体系。结果表明:75%酒精浸泡3 min+0.1%升汞消毒15 min消毒效果较佳,污染率为21.7%,发芽效果较好; 用95%的浓硫酸预处理12 h接种到WPM启动培养基上萌发率为46.0%; 猴面包树种子经过预处理和消毒后接种到WPM启动培养基上遮光处理48 h,发芽率可达74.0%; 将经过启动培养后的外植体切成2～3 cm带有一个节的幼嫩茎段接种在增殖培养基中进行丛生芽诱导,筛选出最佳增殖培养基为WPM+2.0 mg·L^-1 ZT+ 0.2 mg·L^-1 IBA,继代周期60 d,增殖系数最高为3.1/60 d; 将丛生芽切成单株,接种到生根诱导培养基中,筛选出最佳生根培养基为WPM+5.0 mg·L^-1 IBA,生根诱导60 d,生根率达61.3%,平均根数为1.9条,平均根长8.9 cm。将生根苗在荫棚炼苗后,移栽至混合基质(椰糠:菜园土:珍珠岩=1:1:1)中,成活率60.0%。初步建立了猴面包树离体快繁技术体系,为猴面包树的快速繁殖和种质资源保存提供理论和技术支持。

Abstract:

The purpose of this paper was to establish the tissue culture regeneration system by using the seeds of Adansonia digitata. After treated with a suitable pretreatment and seeds sterilizing method, the initial medium was inoculated to obtain a sterile material. After initiation culture, the multiple shoot were induced in the enrichment medium, and then cut into individual plants for rooting induction, and finally established a tissue culture and rapid propagation system. The results were as follows: The optimal disinfection treatment combination of explants was 75% alcohol treatment for 3 min + 0.1% HgCl₂ treatment for 15 min, the contamination rate of explants was 21.7%; The germination rate was 46.0% after pretreatment with 95% concentrated sulfuric acid for 12 h; The A. digitata seeds were pretreated and sterilized and inoculated onto WPM start-up medium for 48 h, and the germination rate was 74.0%; After the initial culture, axillary buds of the explants were cut into 2-3 cm with a section of young stems and inoculated into the enrichment medium and cultured for 60 d for multiple shoots induction, finally, the best value-added medium was selected as WPM+2.0 mg·L^-1 ZT+ 0.2 mg·L^-1 IBA, and the subculture cycle was 60 d with the increment coefficient as high as 3.1; The best rooting medium was WPM + 5.0 mg·L^-1 IBA, and rooting was induced for 60 d with a rooting rate of 61.3%, the average number of roots was 1.9 and the average root length was 8.9 cm. Adding the right amount of IBA can improve the foam root phenomenon and improve the transplant survival rate. After seedling adaptation, the tissue culture seedlings of A. digitata were transplanted to mixed matrix with coconut:vegetable garden soil:perlite(volume ratio 1:1:1), and the survival rate reached above 60.0%. This paper preliminarily established the in vitro rapid propagation technology system of A. digitata, and can provide theoretical and technical supports for the rapid propagation of A. digitata and the preservation of germplasm resources.