| Establishment of highly-efficient in vitro regeneration svstem of Chinese Narcissus was a premise condition for cultivar improvement of Chinese Narcissus with biological and in vitro mutation technology.Using anther,ovary,pedicel and scape of Chinese Narcissus as explants,the influencing factors on the two means of direct and indirect organogenesis were systematically studied in the work in order to obtain the high frequency regeneration system that was suitable for the study of gene transfer and in vitro mutation.In addition,the preliminary study on in vitro mutation with EMS on bulb of Chinese Narcissus to screen mutant was performed in the work to explore the conditions and methods of mutation,which provided the basis for breeding new narcissus cultivar.The main results were as follows:1.The induction,subculture and differenciation of callus of floral organsThe callus inducded by ovary,pedicel and scape of Chinese Narcissus had some similarities, and which had regenerative capacity was the compact callus with a fold or strumae surface,which induction frequencys of three floral organs were respectively 85.0%,73.3%and 66.1%,and which differenciation frequencys were respectively 49.1%,50.0%and 73.1%.Compared several periods of drawing material,the helpful periods for callus induction for three floral organs were all when the flower bud in the bulb without hydroponic culture finished differentiation and had a relatively large degree of maturity.For the induction of callus of ovary,pedicel and scape, different hermone combinations induce different types of callus,but the compact callus with regenerative capacity could be induced only when the 2,4-D and BA were co-used.It is found that the application of 1 mg·L-1BA and 0.1 mg·L-1NAA is helpful to the differenciation of callus of ovary,pedicel and scape.Compared three explants,it's better to use scape as the explant of callus induction,and,though its callus induction rate was lower than ovary and pedicel,it had a faster induced speed and differentiation speed,and had a higher differentiation rate.Anther was also a kind of suitable explant for callus induction.In the work,after the influences of sucrose,agar and other component of medium on callus induction were studied,the results showed that it's helpful for the callus induction and proliferation to decrease sucrose and agar concentration of medium.The anther induced two types of compact and pulp vesicle callus, and only the latter had rgenerative capacity,induction frequency of which was 66.0%,and the differenciation frequency of which was 46.7%in the medium added with 1 mg·L-1BA and 0.1 mg·L-12,4-D.In the study of callus subculture,it was found In the medium added with 1 mg·L-1 BA and 0.1 mg·L-12,4-D,the differenciation frequency was 46.7%.In the study of callus subculture,it was found that only the pulp vesicle callus was able to be subcultured,but it's liable to browning and almost completely browning after 3～4 times' subculture.Through subculturing, imcompact-type callus of vigorous vitality,could be screened.2.Adventitious bud induction of several floral organsWith the ovary,pedicel and scape of Chinese Narcissus as explants to induce adventitious bud induction,it showed that they had different differenciation ability,which of the scape was strongest.In the medium added 5 mg·L-1BA and 0.5 mg·L-1NAA,the differenciation frequency of scape is 56.7%,and its differentiation coefficient reached 8.0.Bulb buds induced was able to developed into intact bulblets through strong sesdling,and the rooting rate of bulblets was 100%on the medium of 1/2 MS(MS)+0.5 mg·L-1NAA.3.In vitro mutation with EMS on bulbThree EMS treatment methods,which were soaking,drop-adding and adding-to-medium, were studied in this experiment.The result showed that the method of soaking had little influence on the lethality rate of in vitro bulb,while the method of adding-to-medium made all the materials to death,and the method of drop-adding' influence lay between the soaking and adding-to-medium.Through comparing three methods,the method of soaking was better.Both of Soaking drop-adding were all had remarkable influences on the differenciation frequency.With 50% differenciation frequency asselection criteria,it was better with 0.3%EMS soaking for 2～6 h or 0.7%EMS soaking for 2h and for the drop-adding method it's better when the EMS concentration ranged 0.1%～0.3%and the treatment duration was 1d.
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