山苍子植株再生体系的优化

Optimization of Plant Regeneration System of Litsea cubeba

【目的】研究优化山苍子茎段愈伤组织诱导和植株再生体系的方法,提高不定芽的分化率和生根率,为山苍子良种的工厂化繁育及遗传转化体系的建立提供技术支撑。【方法】本研究以山苍子茎段节间(不带芽)为外植体,通过比较不同植物生长调节剂对其愈伤组织的诱导、增殖以及不定芽的分化、生根的影响,确定山苍子愈伤组织诱导和植株再生的最适培养基。在此基础上,对获得的再生植株进行移栽试验,比较不同基质对移栽成活率的影响。【结果】山苍子茎段愈伤组织诱导的最适培养基为1/2 MS+0.2 mg·L^(-1)6-BA+0.3 mg·L^(-1)NAA+30 g·L^(-1)蔗糖+7 g·L^(-1)琼脂,其诱导率为100%;愈伤组织增殖的最适培养基为1/2 MS+0.5 mg·L^(-1)6-BA+1.0 mg·L^(-1)NAA+30 g·L^(-1)蔗糖+7 g·L^(-1)琼脂,愈伤组织增殖系数达3.43;诱导不定芽分化的最适培养基为1/2 MS+0.5 mg·L^(-1)6-BA+0.1 mg·L^(-1)IBA+30 g·L^(-1)蔗糖+7 g·L^(-1)琼脂,不定芽分化率为45.59%,平均不定芽数为8.14;生根阶段最适培养基为1/2 MS+0.5 mg·L^(-1)IBA+20 g·L^(-1)蔗糖+7 g·L^(-1)琼脂,不定芽生根率高达93.33%,平均根数为6.74;将生长良好的再生植株进行驯化后,移栽至营养土∶珍珠岩=3∶1(V/V)的混合基质中,其成活率达到83.33%。【结论】本研究优化了山苍子离体再生体系,显著提高了山苍子不定芽的分化率和生根率以及再生植株的移栽成活率,可为山苍子良种的工厂化繁育提供技术支撑。

【Objective】The tissue culture technology of Litsea cubeba is not perfect and cannot satisfy the needs of industrialized breeding.In view of this,this research intends to optimize the stem callus induction and plant regeneration systems of L.cubeba,so as to improve the differentiation and rooting rates of adventitious buds,and provide technical supports for the establishment of industrial breeding and genetic transformation system of L.cubeba elite varieties.【Method】In this study,the stem internodes(without bud)of L.cubeba were used as explants,and the optimum media for callus induction and plant regeneration of L.cubeba were determined through comparing the effects of different plant growth regulators on callus induction,proliferation,adventitious bud differentiation and rooting.On this basis,the transplanting tests of regenerated plants were performed to compare the effects of different substrates on the transplanting survival rates.【Result】The optimum medium for callus induction of stem segments was 1/2 MS containing 0.2 mg·L^(-1)6-BA,0.3 mg·L^(-1)NAA,30 g·L^(-1)sucrose and 7 g·L^(-1)agar,and the induction rate was 100%.The optimal medium for callus proliferation was 1/2 MS containing 0.5 mg·L^(-1)6-BA,1.0 mg·L^(-1)NAA,30 g·L^(-1)sucrose and 7 g·L^(-1)agar with a proliferation coefficient up to 3.43.The optimal medium for adventitious bud differentiation was 1/2 MS containing 0.5 mg·L^(-1)6-BA,0.1 mg·L^(-1)IBA,30 g·L^(-1)sucrose and 7 g·L^(-1)agar with a differentiation rate of 45.59%and an average number of 8.14 of adventitious buds.The optimum medium for rooting of adventitious buds was 1/2 MS containing 0.5 mg·L^(-1)IBA,20 g·L^(-1)sucrose and 7 g·L^(-1)agar,the rooting rate was 93.33%and the average number of roots was 6.74.After domestication,the regenerated plants were transplanted into the mixed substrate with nutrient soil and perlite(volume ratio 3∶1),and the survival rate reached to 83.33%.【Conclusion】This research optimizes the in vitro regeneration system of L.cubeba,significantly improves the differentiation and rooting rates of adventitious buds and the transplanting survival rate of regenerated plants,which can provide a technical support for the industrialized breeding of L.cubeba elite varieties.