Effects of the Fungal Elicitor on the Polysaccharide Content of Dendrobium candidum Protocorms
真菌诱导子对铁皮石斛原球茎多糖含量的影响

The effects of MF24 fungal elicitor on the polysaccharide content of Dendrobium candidum protocorms were studied in this work. MF24 fungal elicitor was prepared in 4 ways and added at 3 dosages. Distilled water was used as the control. The elicitor was added at different time points and then co-cultured with protocorms for different time. The polysaccharide content of protocorms rose to 5.63%, as the mycelium of MF24 was used as the elicitor (elicitor T4) and added at 250 mL·L-1 culture medium (high dosage), increasing by 78.2% compared with the control (3.16%). When elicitor T4 was added at a high dosage at the 14th week and then cultured for 2 more weeks, the polysaccharide content reached the highest value of 5.92%, increasing by 29.0% compared with the average value of 4.59%. The results showed that the polysaccharide content of protocorms may be improved when the mycelium of MF24 is used as the elicitor and added at the later stage of the culture.