铁皮石斛F_1代多糖和醇溶性浸出物变异规律研究

Quantitive variation of polysaccharides and alcohol-soluble extracts in F_1 generation of Dendrobium officinale

采用苯酚-浓硫酸法和醇溶性浸出物热浸法测定11个铁皮石斛F1代家系多糖和浸出物的含量,结果表明5月与2月采集的样品多糖质量分数分别为32.89%~43.07%,25.77%~35.25%,醇溶性浸出物质量分数分别为2.81%~4.85%,7.90%~17.40%,家系间存在显著差异;多糖含量低的亲本通过与多糖含量高的亲本杂交,能显著提高子代多糖含量,杂交优势明显,杂交育种是提高铁皮石斛多糖含量而进行品种选育的有效途径。采收时间显著影响铁皮石斛多糖和浸出物含量,所有家系5月采样多糖含量均高于2月,浸出物含量则相反,但不同家系变化幅度差别很大,各个家系有其自身规律,研究铁皮石斛优良家系（品种）多糖和浸出物积累规律,确定其最佳采收时间,对充分发挥优良品种作用、提高药效具有重要意义。

Using phenol-sulfuric acid method and hot-dip method of alcohol-soluble extracts, the contents of polysaccharides and alcohol-soluble extracts in 11 F1 generations of Dendrobium officinale were determined. The results showed that the polysaccharides contents in samples collected in May and February were 32.89%-43.07% and 25.77%-35.25%, respectively, while the extracts contents were 2.81%-4.85% and 7.90%-17.40%, respectively. They were significantly different among families. The content of polysaccharides in offspring could be significantly improved by hybridization between parents with low and high polysaccharides contents, and the hybrid vigor was obvious. Cross breeding was an effective way for breeding new varieties with higher polysaccharides contents. Harvest time would significantly affect the contents of polysaccharides and alcohol-soluble extracts. The contents of polysaccharides in families collected in May were higher than those of polysaccharides in families collected in February, but the extracts content had the opposite variation. The extents of quantitative variation of polysaccharides and alcohol-soluble extracts were different among families, and each family had its own rules. It would be significant in giving full play to their role as the excellent varieties and increasing effectiveness by studying on the quantitative accumulation regularity of polysaccharides and alcohol-soluble extracts in superior families （varieties） of D. officinale to determine the best harvesting time.keywords：Dendrobium officinale