紫菀再生体系建立及玻璃化苗调控技术研究OA

To establish an efficient and stable in vitro regeneration system for Aster tataricus L.F.,leaf and flower bud explants were utilized to evaluate the effects of hormone combinations[6-BA(6-benzylaminopurine),NAA(1-naphthaleneacetic acid),2,4-D(2,4-dichlorophenoxyacetic acid),KT(kinetin)]and low-temperature(4℃)pretreatment on callus induction and adventitious bud differentiation.Furthermore,the regulatory effects of sucrose concentration and moderate dehydration treatment on vitrified plantlets were systematically analyzed.The results showed that the optimal disinfection protocol for Aster tataricus L.F.explants was immersion in 0.1％HgCl ₂ for 8 minutes.Leaf explants could induce callus formation but failed to differentiate into adventitious buds,while flower buds were identified as suitable explants for constructing an efficient regeneration system.Among these,4 mm flower buds at the mid-flowering stage were optimal for callus induction,and the optimal medium for both callus induction and adventitious bud differentiation was MS+6-BA 1.5 mg/L.The optimal medium for adventitious bud proliferation was MS+6-BA 1.0 mg/L.Compared with ambient temperature culture,low-temperature pretreatment at 4℃for 7 days significantly enhanced the callus induction rate.Agar,sucrose,PEG-6000,and dehydration treatments could all improve the status of vitrified plantlets to varying extents,with the best effect achieved by 50 g/L sucrose treatment,and the recovery rate of vitrified seedlings reaching 60.00％.In conclusion,this study clarified the suitable explant(4 mm flower buds at the mid-flowering stage),optimal explant disinfection protocol(0.1％HgCl ₂ treatment for 8 minutes),and medium formulations for regeneration system establishment(callus induction and adventitious bud differentiation:MS+6-BA 1.5 mg/L;adventitious bud proliferation:MS+6-BA 1.0 mg/L),as well as effective regulatory measures(4℃low-temperature pretreatment for 7 days to promote callus induction,and 50 g/L sucrose to mitigate vitrification).An efficient and stable in vitro regeneration system for Aster tataricus L.F.was successfully established.