继代周期对霍山石斛试管苗生长及培养基成分的影响

Influence of subculture cycle on tube plantlet growth of Dendrobium huoshanense and medium composition

目的研究继代周期对霍山石斛试管苗长势及培养基成分的影响,确定最佳的继代周期时间。方法测定不同继代周期试管苗的株高、分蘖数、鲜质量、叶绿素量及培养基pH、含水量、含糖量的变化,并计算石斛试管苗生长所需的培养基和其他的成本。结果继代周期为40d,试管苗的株高比继代前增加了282.86%,分蘖数比继代前增加了3.5倍,试管苗的鲜质量最大,叶绿素的量趋于最大值;培养基的含水量、可溶性糖的量最低;pH<4.75,已不适合石斛试管苗的生长,石斛苗生长所需成本较低。结论40d为霍山石斛试管苗生长的最佳继代周期。

Objective To optimize the best subculture cycle through studying the influence of subculture time on tube plantlet growth of Dendrobium huoshanense and the change of medium composition. Methods Height, tiller, fresh weight, and chlorophyll content of the tube plantlet and pH value, water content, and sugar content of the medium were measured after different cycles of the subculture, the cost of culture medium for subculture was calculated as well. Results The height of the tube plantlet increase 282. 86%, the tiller increase by 3. 5 times, fresh weight reaches its maximum, chlorophyll content of the tube plantlet almost reaches its maximum after 40 d subculture; while water content and sugar content of the medium are decreased to the lowest point, pH value of medium （〈4.75） could not be suitable to the growth of plantlet. Cost for culturing D. huoshanense plantlets is very low. Conclusion 40 d is the best subculture cycle time for the tube Mantlet culture of D. huoshanense.