刚果12号桉离体组织的多倍体诱导

以刚果12号桉（Eucalyptus 12ABL）下胚轴诱导出的愈伤组织及丛生芽为材料,采用浸渍法、点滴法、混培法等3种秋水仙碱处理法对其进行多倍体诱导.结果表明：在诱导愈伤组织时,浸渍法以处理时间为10 h与药液处理浓度为7 500mg/L、处理时间为22 h与药液处理浓度为2 500 mg/L的2个组合变异率最高,达到40%,点滴法以药液处理浓度为2 500mg/L变异率最高,达到42.9%;在诱导不定芽时,混培法以药液浓度为40 mg/L处理10 d的变异率最高,达到22.5%,点滴法以药液浓度为2 500mg/L的处理变异率最高,达到26.7%.多倍体植株形态特征表现为叶片肥厚宽大,叶色浓绿,茎较粗壮、气孔较大且数目较少,其染色体数目变为2n=4X=44.

Polyploid Induction of in vitro Tissues of Eucalyptus 12ABL

The calli and clustered buds obtained from the hypocotyls of Eucalyptus 12ABL were treated by colchicines through soaking, dripping or adding into the medium to induce polypoids. The results showed that in the soaking method the calli immersed with 7 500 mg/L colchicines for 10 h and 2 500 mg/L for 22 h produced best results with the polyploid inducing rates being up to 40 %; that in the dripping method the calli and clustered buds dripped with 2 500 mg/L colchicines had the best results with the polyploid inducing rate reaching 42.9 % and 26.7 % respectively, and; that in the last method the clustered buds treated for 10 days by adding 40 mg/L colchicines into the medium gave the best results with the polyploid inducing rate being upto 22.5 %. Comparison of the polyploid plants with normal diploid ones in morphology showed that the leaves of the polyploid plants were thicker, larger, dark greener in color, larger but fewer in stomata. The stems were thicker and more vigorous. The chromosome number of polyploid plants was 2n=4x=44, while that of diploid was 2n=2x=22.