杜仲良种选育研究现状及展望

杜仲是我国特有的传统中药材,也是极具潜力的温带胶源树种,在制药、制胶等产业化开发方面具有巨大的利用价值。该文综述了杜仲种质资源收集、保存及性状遗传变异评价,杜仲选择育种、杂交育种和多倍体育种技术与良种选育,以及杜仲无性系繁殖技术等研究现状,指出面向立地条件较差、劳力资源紧张的杜仲栽培地区,发展杜仲栽培以及制药、制胶产业,仍然以数量巨大、收集容易、成本低廉的叶片作为生产原料最为切实可行。在杜仲良种选育中,利用多倍体代谢产物增加等特性,通过诱导配子染色体加倍获得杂种三倍体,则是大幅度提高杜仲叶片含胶量、药效成分含量以及植株产叶量最具希望的途径。在未来杜仲多倍体育种中,应加强杜仲叶片含胶量、药效成分含量等目标性状配合力高的杂交亲本选配,在利用基因剂量效应带来的倍性优势同时,充分利用异源配子结合产生的杂种优势;创制简便易行、成本低廉的杜仲胶、药效成分等次生代谢产物检测技术方法,提高优良无性系选择效率和效果;研发技术环节简约、出圃快、苗木幼化、成本低廉的杜仲无性繁殖技术,加快良种规模生产。可以预见,随着杜仲三倍体的选育成功,通过一轮次多倍体育种过程实现杜仲多目标性状综合改良,必将更为有力地促进以制药、制胶为核心的杜仲绿色循环经济的高效发展。

Status and prospect of improved variety selection in Eucommia ulmoides

Eucommia ulmoides is not only an unique Chinese traditional medicine, but also a potential temperate rubber resource tree species, which has great value in industrialization exploitation of pharmaceutical and rubber production. In this paper, status of collection and conservation of germplasm resources, evaluation of genetic variation in traits, selection breeding, cross breeding, polyploidy breeding and vegetative propagation of varieties in E. ulmoides were reviewed. Leaves with many advantages, such as large quantity, low cost, easy to collect, are the best raw material for pharmaceutical and rubber production when Eucommia spp. plantations were developed in some regions with poor site conditions and labor resource shortage. Because polyploidy breeding could result in an increasing content of secondary metabolites, triploid hybrid production by gametic chromosome doubling may be the most promising way to greatly improve the rubber content and medicinal components of leaves and leaf yield. In future polyploid breeding of E. ulmoides, we should focus on selecting crossing parents with higher combining ability in rubber content and medicinal composition content of leaves. Not only ploidy advantages resulting from gene dosage effects but also heterosis derived from allogametes fusing can be fully utilized. To increase the efficiency of clonal selection, developing a detection techniques with simple and low cost characteristics for secondary metabolites, such as E. ulmoides rubber, active ingredients, is necessary and required. A simple and rapid vegetative propagation technique characterized with low cost is also required to shorten the period of seedling cultivation and speed up high quality seedling production of improved varieties. With the successful development of triploid E. ulmoides, it is predictable that multiple trait improvement via one round polyploidy breeding will promote the development of green circular economy with the core of pharmaceutical and rubber production in China.