Disease of Ganoderma lucidum: Aspergillus

Aspergillus (Aspergillus) belongs to semi-knowing subphylum, Trichoderma, Trichoderma, Cladosporaceae, Aspergillus. There are many kinds of Aspergillus, the most common ones are Aspergillus flavus (A.flavusLink) and Aspergillus Niger (A.nigerVanTieghem).

1. The morphological characteristics of hyphae are colorless, septate and branched, and the hyphae are shorter and thicker than Mucor. The conidiophores are borne on the thick-walled dilated podocytes specialized by hyphae, unbranched, and the tip expands into an apical sac. The surface of the parietal sac produces radiating monolayer or double urination. The conidia are born at the top of the peduncle and finally become an unbranched chain. The apical sac, peduncle and conidium chain constitute the conidium head. Conidia are born at the top of peduncles and have different colors and shapes, which is one of the bases for classification. On PDA medium, the colony of Aspergillus flavus was yellow at first, then yellowish green, and finally brownish green, and the conidia were spherical and yellowish green. The colony of Aspergillus Niger is white at first, then black, and the conidia are spherical and carbon black.

two。 Morbidity regularity

The main results are as follows: (1) Aspergillus widely exists in soil, air and decaying organic matter, and conidia are transmitted by airflow.

(2) Aspergillus mainly uses starch and has the ability to decompose cellulose. Bamboo culture bed frame is easy to be produced under the condition of high humidity and poor ventilation. The pH suitable for Aspergillus growth is nearly neutral. The optimum growth temperature of Aspergillus Niger and Aspergillus flavus was 20-30 ℃ and 25-30 ℃, respectively. It could survive for 30 minutes in 45 ℃.

3. After the damage symptom matrix was contaminated by Aspergillus flavus, the colony was yellow to yellowish green, Aspergillus Niger was black, grew and spread quickly, absorbing nutrients and water. Aflatoxin secreted by Aspergillus flavus is a strong carcinogen. Aspergillus Niger and Aspergillus fumigatus produce high concentrations of spores that invade the lungs and are prone to aspergillosis or "mushroom worker lung disease".

4. Prevention and cure method

(1) do a good job in the sanitary work of cultivation rooms and cultivation grounds, so as to put an end to pollution sources.

(2) the culture medium is strictly sterilized, and sawdust and straw should be stacked or sterilized after exposure to the sun.

(3) the addition of 1 × 10-6 or 5 × 10-6 carbendazim could inhibit the growth of Aspergillus flavus and black mold.