元宝枫古树组织培养快速繁殖体系研究

Research on Tissue Culture and Rapid Propagation System of Acer truncatum Ancient Tree

【目的】元宝枫籽油中含有丰富的神经酸,被国家林业和草原局确定为珍贵的木本油料树种;同时因其叶片独特而被作为绿化行道树而广泛种植,因此开展元宝枫观赏和药食同源研究意义重大。而元宝枫优良的种质资源大多是古树,其数量稀少且生长状态不佳,亟需将其繁殖保存以便保护利用。【方法】为了更好的研究元宝枫及对优质元宝枫种苗进行保存,以内蒙古元宝枫古树茎段为试验材料进行组培快繁的研究。春季取元宝枫古树枝条通过水培诱导新芽作为外植体,可以减少代谢产物的分泌进而避免无菌苗褐化。用不同次氯酸钠消毒时间、不同的培养基和不同的激素浓度及组合,以增殖率、生根率和生长状态作为评价指标,筛选出最适合的初始培养基、增殖培养基和生根培养基。【结果】采用75%酒精和1%次氯酸钠依次浸泡消毒1 min和10 min为最适宜的灭菌方案,外植体污染率仅为30%且有新芽萌出或伸长。1/2 MS+20 g·L^(-1)蔗糖+7 g·L^(-1)琼脂粉为元宝枫古树最适初始培养基,外植体无愈伤化现象;MS+30 g·L^(-1)蔗糖+TDZ 0.01 mg·L^(-1)+ZT 0.2 mg·L^(-1)+7 g·L^(-1)琼脂粉为最适增殖培养基,外植体分化旺盛且生长状态良好;1/2 MS+15 g·L^(-1)蔗糖+7 g·L^(-1)琼脂粉+浸泡100 mg·L^(-1)的IBA 5 min为最适生根培养基,生根率可达84.6%。【结论】本研究以内蒙古元宝枫古树水培新枝为外植体的组织培养快繁体系的构建,为进一步保护古树和利用元宝枫这一优良种质资源奠定了基础。

【Objective】Seed oil of Acer truncatum contains plentiful nervonic acid,so it was identified as a precious woody oil tree species by National Forestry and Grassland Administration;meanwhile,it is widely planted as a green street tree because of its unique leaves.Therefore,it is of great significance to carry out research on the ornamental and medicinal food homology of A.truncatum.Most of the excellent germplasm resources of A.truncatum are ancient trees,which are scarce in number and in poor growth condition,and urgently need to be reproduced and preserved for conservation use.【Method】In order to better study A.truncatum and to preserve the high-quality A.truncatum seedlings,the stems of the A.truncatum ancient tree in Inner Mongolia were used for tissue culture and rapid propagation.In spring,the branches of A.truncatum ancient tree were used to induce new shoots through hydroponics as explants,which could reduce the secretion of metabolites and avoid the browning of sterile seedlings.Using different sodium hypochlorite disinfection times,different media and different hormone concentrations and combinations,the most suitable initial media,proliferation media and rooting media were screened out with proliferation rate,rooting rate and growth status as evaluation indicators.【Method】The results showed that it was the most suitable sterilization using 75%alcohol soaking for 1 minute and 1%sodium hypochlorite soaking for 10 minutes,while the explant contamination rate was 30%and new shoots were emerged or elongated.While 1/2 MS+20 g·L^(-1) sucrose+7 g·L^(-1) agar was the most suitable initial medium for A.truncatum ancient tree,and the explants had no callus phenomenon.And MS+30 g·L^(-1) sucrose+TDZ 0.01 mg·L^(-1)+ZT 0.2 mg·L^(-1)+7·L^(-1) agar was the most suitable medium for proliferation,then the explants were well differentiated and grow well.While 1/2 MS+15 g·L^(-1) sucrose+7 g·L^(-1) agar+100 mg·L^(-1) IBA for 5 min was the most suitable rooting medium,the rooting rate could reach 84.6%.【Conclusion】In this study,the establishment of a tissue culture rapid propagation system with hydroponic new branches of A.truncatum ancient trees in Inner Mongolia as explants laid the foundation for further conservation of ancient trees and utilization of A.truncatum as an excellent germplasm resource.