濒危药用植物竹节参种子形态特征与萌发特性研究

Seed Morphology and Germination Characteristics of Endangered Plant Panax japonicus

[目的]探索竹节参种子的休眠特性,研究能够促进其种子萌发的有效方法。[方法]通过测定竹节参种子的千粒重、含水量、生活力以及不同浓度激素处理下种子的萌发率、根长和茎长,为竹节参高效繁育提供理论和技术支撑。[结果]竹节参在鲜果成熟时,种胚处于球形胚阶段,发育不完全,种子具有休眠特性。种子形态休眠自然解除需180 d,湿沙储藏能够有效促进竹节参种子完成“胚后熟”过程,加快种子萌发。竹节参种子籽粒饱满,含水量为54.64%,生活力为85.12%,250 mg/L GA3可有效提高竹节参种子的萌发率,该处理下竹节参茎长的平均值达到54 mm,其次是150mg/L IAA和25 mg/L 6-BA处理,茎长度分别为23 mm和20 mm。[结论]在竹节参种子繁育过程中,湿沙储藏结合250mg/L GA3浸种处理可有效提高种子发芽率,使出苗更加整齐,可作为竹节参高效繁育的重要手段。

[Objective]The aim was to explore the dormancy characteristics of Panax japonicus seeds and put forward effective methods to promote the seed germination.[Method]An experiment was conducted to provide theoretical and technical supports for high-efficiency breeding of P.japonicus.The indexes like thousand-grain weight,moisture content,viability,and seed germination rates,as well as the length of stem and root were measured under different phytohormone treatments.[Result]The matured seeds with incompleted embryos(globular proembryo stage)have dormancy properties.It took 180 days for the dormant seeds to be released naturally.Stratification with wet sand could effectively promote the“embryo post-ripening”process and seed germination of P.japonicus.The seeds of P.japonicus were plump,with water content of 54.64% and viability of 85.12%.250 mg/L GA3 could effectively improve the seed germination of P.japonicus.The average stem length of P.japonicus under 250 mg/L treatment was 54 mm,while the average stem length under 150 mg/L IAA and 25 mg/L 6-BA treatments were 23 mm and 20 mm,respectively.[Conclusion]Wet sand stratification combined with application of 250 mg/L GA3 could effectively improve the seed germination rate and make the seedlings more neatly,which could be used as a pivotal means of high-efficiency breeding of P.japonicus.