Studies On Tissue Culture And Regeneration Of Spiraea Cantoniensis Lour.

This paper mainly dealt with the study on stems and leaves as explants for regenerated plantlets of Spiraea cantoniensis.By means of orthogonal experimental design and statistical analysis method,the affected factors,existing problems of propagation and the relevant solutions were discussed;the technique system of tissue culture was established with best culture medium and procedure.The main results were as follows:1.May was the best season for explants taking on Spiraea cantoniensis.The initiation rate could be up to 82.50%.The contaminated rate was 32.50%.2.For disinfection 0.1%solution of HgCl₂ for 5 minute was the best to stems.The germination rate and contaminated rate separately were 73.33%and 13.33%.0.1%solution of HgCl₂ for 3 minute was the best to leaves.The germination rate and contaminated rate separately were 43.33%and 40.00%.3.Buds induction of stemsThe explants were stems in this year.The best initiation medium for stems was MS medium with 6-BA 2.0 mg/L and NAA 0.1 mg/L,the initiation rate was 84.71%,and the average height of shoots reached 2.10cm.4.Callus induction of leavesThe explants were new leaves in March.MS medium adding 6-BA 1.0 mg/L,NAA 0.50 mg/L and 2,4-D 0.05 mg/L was Callus induced from leaves,the induction rate was 58.18%,and the callus was yellow-green and close.5.Proliferating and differentiating cultivation of callusHighly proliferating callus was obtained from the leaves following cultivation on MS medium supplemented with 6-BA 2.0 mg/L,2,4-D 0.1 mg/L and NAA 0.05 mg/L.The proliferating rates could be up to 86.21%.The best culture medium for callus buds differentiating was MS with 6-BA 1.0 mg/L and NAA 1.0 mg/L.The regenerating rate was 65.00%.But the shoots were tenuous and weren't suitable for rooting.6.Sprout proliferating cultivationThe optional proliferating buds culture medium from stems and shoots was MS supplemented with 6-BA 1.0 mg/L,NAA 0.1 mg/L and IBA 0.5 mg/L,on which proliferation rate was 5.83 times after 30 d.7.Rooting cultureRegenerated shoots could produce roots in 1/2 MS medium containing IBA 0.1 mg/L and AC 0.1%,in which the rooting rate was 71.36%,the average number of roots was 5.13, the average length of root was 3.57 cm.8.TransplantingPlantlets were transferred to the medium with ratio of 1:1:1 of vermiculite and ruby mica and sands,the survival rate could reach 80.00%,and the seedlings grew very well.