Tissue Culture And Rapid Propagation Of Camellia Oleifera 'Yangxin Micha'

Camellia oleifera 'Yangxin Micha' is recognized as a good local variety in Yangxin county,Hubei province.Traditional seedling propagation and conventional vegetative propagation can not meet the needs for further genetic breeding and extension of elite varieties of Camellia oleifera.Therefore,it is necessary to conduct the researches on tissue culture and rapid propagation of this variety.In this paper,researches on medium formuli and culture condition of rapid propagation and plant regeneration via tissue culture were carried out,and based on which,technology system of rapid propagation and plant regeneration was established.Main results were as follows:(1)Explants sampling and sterilization.It was suitable to collect stem segments with axillary buds as explants from April to June and sterilized these explants with 0.1%HgCl2 for 8min,the contamination rate was 7.33%,the browning rate was 5.87%,and the germination rate reached 83.11%.For Leaf explants,it was suitable to sterilized them with 2.5%NaClO for 20 min,the contamination rate was 5.00%,the browning rate was 28.34%.If the leaf explants were cultured in dark for 7 days,browning could be inhibited effectively.(2)Rapid propagation system.The best initiation culture medium for stem segments with axillary buds was MS + 6-BA 1.0 mg/L+NAA 0.5 mg/L,the germination rate was 55.06%;the best medium for shoots proliferation was MS+ 6-BA 2.0mg/L +NAA 0.1mg/L,the proliferation multiples and the effective shoots rate reached 5.10 and 80.35%respectively;the best shoots strength medium was MS;the best rooting medium was 1/2MS+NAA2.0mg/L+ sucrose 20 g/L,rooting rate reached 68.72%and the average root length was 2.98cm;by dipping the low ends of shoots in 1000 mg/L NAA for 20s and then culturing the shoots in 1/2MS,73.02%of the shoots rooted and the average length reached 3.64cm;the survival rate of plantlet transplanted reached 80%.(3)Regeneration system.The best medium for callus induction from leaf explants was MS + 6-BA 0.5 mg/L + NAA0.7mg/L,the callus induction rate was 98.07%.But no adventitious shoots occurred from calli.The best medium for adventitious shoots regeneration from stem callus was MS + 6-BA 3.Omg/L + 2,4-D 2.0 mg/L,the shoot induction rate was 32.96%,and the average adventitious shoots number was 2.88.