Analysis of Technical Problems in Polyporus umbellatus Cultivation

Polyporus umbellatus comes in three colors: black, gray, and white, respectively called black sclerotium, gray sclerotium, and white sclerotium. For Polyporus umbellatus sclerotia that have grown for more than one year, the surface is black and glossy, the texture is dense and highly tough, and the cross-section is white or pale yellow, with some parts able to germinate hyphae; gray sclerotium has a gray or grayish-yellow surface, dull luster, a certain degree of toughness and elasticity, and a white cross-section, germinates very quickly under suitable temperature conditions, and can be used as medicine or kept as seed for asexual propagation; white sclerotium (that is, young sclerotium) has a pure white skin, breaks easily when pinched by hand, has a tender white cross-section that can germinate hyphae, has a high moisture content, and appears rice-yellow after drying. These three colors of Polyporus umbellatus do not exist as separate individuals; they usually coexist as one body, merely representing different growth and development stages. The growth increments at each growth stage vary greatly between the same plant or different plants, which is to say that its growth time cannot be measured by the size of the individual.

1. About the problem of insect pests Various types of insect pests occur on the logs used for Polyporus umbellatus cultivation. According to analysis, most are caused by mites, millipedes, and other pests. The control method is very simple: use phoxim, mix it according to the lowest concentration stated in the instructions, and pour it into the cultivation pile, generally about a 1000-fold dilution. After that, pay attention to prevention, such as clearing the surrounding environment and cutting off insect sources. You can also spray insecticide around the area once every 3 to 7 days to prevent and cut off the channels of pest sources. 2. About the problem of miscellaneous fungi occurring on the logs Because logs have relatively low available nutrients, miscellaneous fungi generally do not easily infect them. However, when cultivation has lasted about half a year and the logs have long been in a dark, damp environment, they are also very susceptible to invasion by miscellaneous fungi, generally wood-rotting fungi, that is, true fungi. Preventive measures are to select high-quality spawn, master suitable moisture, temperature, and other conditions so that Armillaria mellea grows healthily, and have it come into close contact with Polyporus umbellatus as soon as possible to form a good symbiotic relationship. However, once miscellaneous fungi occur, you can brush the fungal material with about a 100-fold Xiaoduwang solution, and then manage it as usual. 3. About the problem of Polyporus umbellatus disappearing When the cultivation pile is opened and no large sclerotia of Polyporus umbellatus can be found, or even no small sclerotia, this is the so-called “Polyporus umbellatus disappearance.” There are three reasons: first, the Polyporus umbellatus (sclerotium) seed used for asexual cultivation has problems, either infected with viruses or pathogens or having lost activity, and has been “eaten” by Armillaria mellea; in some cases, the Polyporus umbellatus spawn used for sexual cultivation may have aged and degenerated, or lost activity due to unsuitable conditions such as heat during transport, resulting in its nutrients being completely absorbed by Armillaria mellea after cultivation; second, the Armillaria mellea fungal material belongs to multi-generation culture and itself has no ability to supply nutrients, so Polyporus umbellatus has no nutrient source and disappears, or the Armillaria mellea spawn used for sexual cultivation has aged and degenerated, causing low resistance and making it unable to supply nutrients to Polyporus umbellatus; third, if there are no problems with the Polyporus umbellatus seed and the Armillaria mellea spawn, the author believes that to a large extent it is improper management, such as the moisture problem. Armillaria mellea can grow normally in water, while Polyporus umbellatus requires a soil moisture content of 30% to 40%. If the moisture is slightly high, Polyporus umbellatus cannot absorb nutrients from the Armillaria mellea rhizomorphs due to insufficient aeration; if the moisture is too high, Polyporus umbellatus loses activity due to insufficient aeration. At this time, the Armillaria mellea rhizomorphs will very naturally absorb nutrients from the Polyporus umbellatus sclerotia, ultimately leading to the “disappearance” of Polyporus umbellatus. Generally, watering once about every half month is enough to meet the water needs of Polyporus umbellatus. 4. About the problem of slow growth Polyporus umbellatus is a long-cycle organism and generally takes about three years to grow to maturity. After half a year of cultivation, Polyporus umbellatus is about the size of a small piece of ginger, which is normal. Under general conditions, the Armillaria mellea rhizomorphs need about two months to come into close contact with Polyporus umbellatus, after which they still go through a stage of nutrition and counter-nutrition before entering the normal supply stage. Being able to grow to the size of a small piece of ginger in half a year is normal, and after that there are still more than two years, during which a single piece can generally reach a weight of more than 250 grams. 5. About the temperature problem The normal growth temperature of Polyporus umbellatus is between 14 and 28°C. After reaching 30°C, it will automatically enter a physiological dormancy period, so summer management should be even more careful. Covering the cultivation pile with leaves, weeds, straw mats, or similar materials as soon as possible to create a comfortable growing environment for Polyporus umbellatus is an effective measure for obtaining high yields.