Studies On Tissue Culture Of Eucalyptus Cloeziana

Eucalyptus cloeziana is one species of Eucalyptus which was introduced from Australia, it is suitable for cultivating as big-diameter timber. The rapid propagation of Eucalyptus cloeziana was studied by tissue culture and the results of preliminary experiments as follows:1.Taking stem segments as explant, modified MS₁ medium supplementedwith 0.2mg/L 6-BA and 0.2mg/L NAA was optimal for induction of axillary bud,there was significant difference between different individual plants ininducement frequency, the inducement frequencies of three individual plants(DH₁, DH₂, DH₃) were 28.6%, 32.4% and 5% respectively.2.There was not significant difference between different individual plants of Eucalyptus cloeziana on subculture. the modified MS₁ medium supplemented with 6-BA 0.2mg/L and NAA 0.2mg/L was optimal for subculture at earlier stage and the reproduction multiple was more than 3, the small bud was increasing after one year of subculture, then, modified MS₁+ 6-BA 0.2mg/L +NAA 0.25mg/L was used for subculture in turn.3.The effect of subculture was significant when cultured under different light conditions. It was optimal for subculture when cultured under the light intensity of 14001x (12h/d) after 7d without illumination; when the light intensity was up to 22001x, the leave callus had become seriously; while the light intensity was just 8001x, the vitrification of buds had become seriously.4. There was significant difference between different individual plants of Eucalyptus cloeziana on rooting. Taking modified MS₁ as basal medium, the rates of rooting of HD₁ was several times even more than ten times than those of DH₂ on every medium. The highest rooting rate of DH₁ was up to 93.8% when NAA was 1.5mg/L, but they are all abnormal roots(no lateral root and no fibril); the highest rate of normal root was 33.4%(but these roots have less lateral roots...