铁皮石斛组培苗生根条件优化研究

【目的】培养生根优良的铁皮石斛组培苗，提高移栽成活率。【方法】在生根培养基中添加不同激素配比（1.0~3.0 mg/L NAA、0.5 mg/L 6-BA）进行铁皮石斛组培苗生根培养，并采取正交试验考察光照强度、pH和琼脂用量对铁皮石斛组培苗生根效果的影响。【结果】随着MS培养基中NAA浓度的升高，试管苗的鲜重和生根率呈逐渐降低的趋势，以添加NAA 1. 0 mg/L（处理1）和NAA 2. 0 mg/L（处理3）的试管苗长势最好。极差分析和方差分析结果表明，在3个培养条件中，对试管苗生根的影响大小表现为光照强度>琼脂用量>pH值，生根培养基3因素最优水平组合为光照强度2000 lx，pH 5.5，琼脂用量8.0 g/L。【结论】铁皮石斛试管苗适宜的生根培养基为1/2MS + 10%香蕉泥 + NAA 1.0 mg/L + 2%蔗糖 + 0.05%活性炭，适宜的生根条件为光照强度2000 lx、琼脂用量8.0 g/L、pH 5.5。

Rooting condition optimization of Dendrobium officinale plantlets

【Objective】This research cultured excellent Dendrobium officinale plantlets in order to improve the survival rates of transplanting plantlets. 【Method】In the rooting culture medium of Dendrobium officinale with different hormone combinations（1.0-3.0 mg/L NAA， 0.5 mg/L 6-BA）， the orthogonal experiments of light intensity， pH， and agar amounts were adopted to test the Dendrobium officinale rooting effects. 【Result】As the NAA concentration in MS medium increased， the fresh weight of test-tube plantlet and its rooting rate gradually decreased， and adding NAA 1.0 mg/L （treatment 1） and NAA 2.0 mg/L （treatment 3） were optimal for test-tube plantlet growth. From the range and variance analysis results， under the 3 culturing conditions， the effects on Dendrobium officinale were ranked in the order of illumination>agar amount>pH values， and the optimal combination of the 3 factors for rooting medium was A3B2C3. 【Conclusion】The optimal Dendrobium officinale rooting plantlets medium was 1/2MS+10% mashed banana+NAA 1.0 mg/L+2% cane sugar+0.05% active carbon， and the suitable rooting conditions were light intensity 2000 lx， 8 g/L agar content， and pH level 5.5.