Some research results on the growth and development of Black Ganoderma at Vietnam National University of Agriculture

Ganoderma lucidum was discovered very early and is famous for its functions. In the book "The Classic of Herbal Medicine" published more than 2000 years ago, Ganoderma, ranked first among the top grade medicine and even ranked higher than ginseng, is a miraculous herb and has a lot of good functions. If used for a long time, Ganoderma is not only unharmful but it also helps increase our lifespan.

Today, when science and technology has developed, Ganoderma lucidum has been proven by scientists in the world to be helpful in the treatment of diseases: cancer, high blood pressure, diabetes, cardiovascular disease, mental depression, hepatitis. With such miraculous functions, Ganoderma lucidum has been researched and cultivated in many parts of the world such as Japan, Korea, China,... Overall, Vietnam has suitable conditions for the development of the mushroom industry.

In recent years, VNUA as well as the staff of the Faculty of Biotechnology has been interested in conducting many studies on the growth and development of some species of fungi in general and Ganoderma in particular. This article would like to introduce some research results on the growth ability of Ganoderma lucidum at the Vietnam National University of Agriculture.

Evaluation of growth and development of some species of black gaoderma on sawdust substrate supplemented with buckwheat bran in the nursery stage:

In Vietnam, there is a great prospect for the cultivation of Ganoderma lucidum due to the abundance in raw materials and human resources. There are quite a few resources for mushroom farming from the agriculture and forestry sectors of our country. Sawdust is a versatile material with a very high carbon content, but it is very poor in nutrients. Therefore, in order to improve the mushroom cultivation efficiency as well as shortening the time for cultivation, it is necessary to mix more supplements. The main supplements are usually buckwheat bran, corn bran, sugar, etc. These ingredients will provide the necessary substances for the fast growth of mycelium.

The ingredients are adjusted and carefully mixed and packed into bags. After autoclaving, the inoculation is carried out. When the inoculation is completed, the bags will be transferred to the mycelium growing room to monitor the growth and development of the mycelium. We have evaluated and investigated the growth of mycelium of Ganoderma lucidum species on different supplementation ratio of buckwheat bran. The results are described in the following tables:

Table 1. Effect of sawdust substrate supplemented with buckwheat bran on the growth of Ganoderma lucidum Ga17 

Table 2. Effect of sawdust substrate supplemented with buckwheat bran on the growth of Ganoderma lucidum Ga20

Table 3. Effect of sawdust substrate supplemented with buckwheat bran on the growth of Ganoderma lucidum Ga21

- CT 1: 97% sawdust + 3% barley bran

- CT 2: 95% sawdust +5% barley bran

- CT 3: 93% sawdust + 7% barley bran

- CT 4: 91% sawdust + 9% barley bran

After 7-8 days of inoculation, white filaments from the ganoderma starts to grow on the surface of the bag. The filaments attached to the material growing outside the bag are very weak and develop relatively slowly. About 14 days after inoculation, the growing fibrous system begins to be stronger and gradually thickened. According to the above tables, CT1 (97% sawdust + 3% buckwheat bran) has the lowest average fiber growth rate (Ga17: 3.49 mm/day; Ga20: 3.61 mm/day; Ga21: 3.60 mm/day). CT2 (95% sawdust +5% bran), CT3 (93% sawdust + 7% barley bran), CT4 (91% sawdust + 9% barley bran) has no statistical difference.

When the mycelium has grown up to 1/2 bag, loosen the cotton button and move them to the nursery house to create favorable conditions for the fungus to form its bodies

Figure 1. Mycelium after 7 days of inoculation (Ga17)

Figure 2. Mycelium after 16 days of inoculation (Ga17)

Figure 3. Mycelium after 7 days of inoculation (Ga20)

Figure 4. Mycelium after 16 days of inoculation (Ga20)

Figure 5. Mycelium after 7 days of inoculation (Ga21)

Figure 6. Mycelium after 16 days of inoculation (Ga21)

Evaluation of growth and development of some species of Ganoderma on sawdust substrate supplemented with buckwheat bran in fruiting stage

The ability to form its bodies, the productivity and quality of mushrooms are important criteria that have a decisive meaning to the yield of Ganoderma lucidum. Continuing to monitor the experiment, we obtained the following results:

Table 4. Effect of sawdust substrate supplemented with buckwheat bran on the time of sprouting and maturation of fruit bodies

Table 5. Fruiting body morphology of Ganoderma lucidum species

Figure 7. Fruiting body morphology of Ganoderma

Table 6. Effect of sawdust substrate supplemented with buckwheat bran on biological performance of Ganoderma lucidum

Based on the table above, it is clear that the Ganoderma lucidum grown on tbe sawdust supplemented with barley bran has the highest biological performance in CT3 and CT4 (8.57%); The Ganoderma Ga20 has the highest biological performance in CT2 (15.29%) and the Ganoderma Ga21 has the highest biological performance in CT3 (15.20%).

Some pictures of rotten ganoderma fruiting bodies:

Figure 8. Image of moldy fruiting bodies of Ganoderma lucidum

Figure 9. Images of fruiting bodies damaged by destructive pests

Figure 10. Image of the fruit body damaged by stem borer

Conclusion

Through the study, based on our initial assessment of the growth and development ability of Black Ganoderma on sawdust substrate supplemented with buckwheat bran, the species Ga20 with CT 2 (95% sawdust + 5% bran) has the highest cover rate in the shortest time (29 days) and the fastest average growth rate (4.14mm/day); the highest biological efficiency (15.29%). In the fruiting stage, the species Ga17 with CT 2 takes the shortest amount of time to form its body and mature (26 days and 86 days respectively).

In conclusion, with the available raw materials such as sawdust, the use of sawdust in black ganoderma farming is economically viable and contributes to the environmental protection.