Seed Dormancy Characteristics And Rapid Propagation Of Seedlings Of Styrax Faberi

Styrax faberi Perk.is a good plant for ornamental flower,ecological restoration,medicinal and oil use.It has broad prospects for development.However,the seed of S.faberi has dormancy characteristics.Therefore,market development must solve the problem of rapid propagation.In this study,seed dormancy characteristics were studied from the aspects of seed biological characteristics,physical permeability,and biological characteristics of endogenous inhibitors and the rapid propagation of seeds and seedlings was studied from seed,in vitro culture and cutting propagation.The main findings are as follows:?1?The results of seed dormancy characteristics showed that the seed dormancy of S.faberi was mainly caused by seed-shell disorders,lack of endogenous hormones required for germination,and germination inhibitors in different parts of seed.The germination of Arabidopsis seeds treated with extracts from different parts of S.faberi seed showed that the inhibitors activity at different parts of the seed was seed-shell<embryo<endosperm.The seed germination of Arabidopsis seedlings treated with different solvent extracts and the related gene expressions of GA and ABA during the germination process showed that the germination inhibitory activity of different solvent extracts of endosperm was ethyl ether solubility<methanol solubility<water solubility,indicating that the water solubility germination inhibitors in the endosperm of S.faberi are the most.The expression of genes related to GA and ABA during germination of Arabidopsis seeds treated with different solvent extracts of S.faberi endosperm showed that these inhibitors influenced the germination of seeds by affecting the synthesis and metabolism of GA and ABA.?2?Research on rapid propagation of seedlings1)Research on seed reproduction showed that since the seed of S.faberi was comprehensive dormancy,the highest germination rate obtained by low temperature stratification,acid etching and GA₃ treatment alone was only 16%in this experiment.Low temperature stratification combined with acid etching and GA₃ combined with acid etching can obtain germination rates of 46.6%and 43.33%,respectively.While the germination rate obtained from GA₃ treatment combined with low temperature stratification only 35.67%.Low temperature stratification for 60 days combined with acid etching for 2 hours and GA₃1500 mg·L^-1 for 5 hours significantly increased the seed germination rate,which reaching54%.The changes of soluble sugar and soluble protein in the sand culture process after acid etching indicate that acid etching can accelerate the metabolic transformation of soluble sugar and soluble protein and promote seed germination.2)The results of the in vitro culture rapid propagation of S.faberi showed that the proliferation coefficient of the S.faberi stem segment in the medium of MS+0.5 mg·L^-16-BA+0.05 mg·L^-1 NAA was the highest,which reaching 5.7.Indirect rooting method can be used to obtain the tissue culture seedlings with high rooting efficiency and suitable for large-scale production.The treatment with 200 mg·L^-1IBA for 15 min and then transferred to 1/2 MS blank medium has the best effect.The rooting rate reached 93.3%.3)The results of cutting propagation of S.faberi showed that:the rooting type of S.faberi was surface rooting.Four kinds of growth regulators could significantly improve the cuttings rooting index,the most significant effect on hardwood cutting by the treatment of IBA,followed by IAA,NAA and GA₃ treatment.Orthogonal test results show that the best cutting rooting hormone treatment was 500 mg·L^-1 IBA treatments for 30 min.The rooting rate of different branch part from high to low was as follows:the upper part,middle part and the basal part.This study preliminarily explored the dormancy characteristics of S.faberi and obtained the best conditions for seed,in vitro culture and cutting propagation,providing a theoretical basis and practical techniques for the breeding,application for S.faberi.