湿地松的组织培养及植株再生

Tissue Culture and Plant Regeneration of Pinus elliottii

在以湿地松实生无菌苗带子叶顶芽为外植体诱导丛生芽的过程中,激素的种类及浓度、处理时间等对丛生芽的诱导影响较大,表现为:单独使用6 BA即可诱导丛生芽分化,但NAA与6 BA协同作用效果更佳;外植体在改良GD+5mg/L6 BA+0.1mg/LNAA的培养基上培养4～5周,其丛生芽诱导率最高达95%。将丛生芽单个切下继代培养在改良GD+3.5mg/L6 BA+0.05mg/LNAA的培养基上时增殖较快。改良GD培养基中添加0.05～0.1mg/L生长素(NAA)或0.5g/L活性炭(AC)能明显促进丛生芽伸长;培养基中的大量元素减半则不利于湿地松丛生芽的伸长生长。将伸长的丛生芽单个切下置于生根培养基中,4周后生根率达53.3%,移栽成活率达85%。

Axillary buds were induced when the explant sources were the aseptic seedlings without roots of P.elliottii.6-benzylaminopurine(6-BA) and kinetin(KT) were both effective at inducing buds formation,but 6-BA was more potent than KT.6-BA in combination with NAA in modified Gresshoff and Doy(GD) medium increased bud production compared with the medium with cytokinin only.The concentration of 6-BA and NAA and the length of exposure to the cytokinin significantly influenced bud induction.The highest inducing rate of axillary buds was up to 95% on the modified GD medium supplemented with 5.0 mg/L6-BA and 0.1 mg/L NAA for 4～5 weeks.The buds were propagated most rapidly when subcultured on the medium of modified GD containing 3.5 mg/L 6-BA and 0.05 mg/L NAA.The addition of NAA(0.05～0.1 mg/L) or activated charcoal(0.5 g/L) to basal medium could greatly promote slash pine shoots elongation and growth.Reduced concentration of minerals failed to enhance shoot elongation.Roots were formed when excised shoots were planted on modified GD 1/2 medium supplemented with 0.05 mg/L NAA for 4 weeks.The rooting rate was 53.3%.The surviving rate was 85% when the rooting shoots were moved to the greenhouse.