Study On The Technical System Of Stem Section And Embryo Culture In Ziziphus Jujuba Mill

The stems and embryos of Ziziphus Jujuba Mill were used for material to establish the technique system of tissue culture. The frequency of contamination in the culture of stem sections was very high. It was necessary to select the explants and the method of surface-sterilizing. The study of embryo in vitro culture included:effects of embryo developmental stages on the culture results with immature embryo culture,while with mature embryo culture,it covered germination,subculture and rooting. The results were as follows:(l)The stem sections with a bud from one-year-old root sprouts were optional explants. When sterilized with 75%alchol (20min)+0.1%HgCl2 (5min),the frequency of contamination and browning was very low,and only 66.7% of them survived.(2)The stems derived from the mature trees had higher infection frequency. The contamination was caused by a kind of fungi.(3)Best initiation medium for stem sections culture was MS+1.0mg/L6-BA+0.1mg/LNAA.Best subculture medium of stem sections culture was MS+1.0mg/L6-BA+0.05mg/LNAA.The theoretical rate of multiplication could reach 1.3 x 106 per year.(4)The embryo developmental stages had significant effect,in immature embryos culture. Younger embryos had lower rate of germination and higher rate of callus induction and embryogenesis than the more mature embryos(5)In mature embryo culture the explants would have the highest rate of germination,and the tube-plantlets grew the fast on the MS medium without any kind of phytohormone.The best medium for shoot-multiplication was MS+l.Omg/L 6-BA+O.lmg/L NAA.The rate of multiplication could reach 3.0with 30 days being its subculture period,and the theoretical rate of multiplication could reach 6.4x105per year. The suitable rooting medium was MS+IBA0.8mg/L.