Study On Physico-chemical Properties Of Substrate To The Industrial Cultivation Of Pleurotus Eryngii

Pleurotus eryngii is a well-known medical fungus, Pleurotus eryngii of perfect market prospects and the industrial cultivation techniques involving this rare edible mushroom have been the object of much research in recent years. The cultivation of it has been widely studied. Researches focused on mushroom culture substrates in the ratio of raw materials, species selection, etc., but rarely in the culture substrates of the physical and chemical properties.Changes in culture substrates physical and chemical properties impact on mushroom production is urgently needed in-depth study. Finding out the impact of laws which can be applied to actual industrial production, save culture substrates and increase mushroom production play important guiding roles.In my experiment, raw materials used in industrial cultivation mushroom sawdust, corn cob, cottonseed hull, wheat bran, rice bran, corn flour, soybean physical and chemical properties were studied to explore suitable culture substrates for industrial cultivation and form the theoretical basis for the design formula.The main results are as follows:1. In all the carbon source suitable for industrial cultivation, corn cob had the strongest holding water capacity with the value 2.95, sawdust second and cottonseed hull minium with the value 2.19. There were wheat bran, rice bran, corn flour and soybean four kinds of nitrogen sources, the water holding capacity of wheat bran was stronger than the other three nitrogen sources with the value 3.03; the water holding capacity of corn flour is minium, only 0.97. Therefore, increasing the amount of corn cob and wheat bran should be a great method to improve the water holding capacity of the substrate. The water holding capacity of different corn cob particle sizes were also mentioned. X2 had the strongest water holding capacity with the value 3.01. As the most used carbon source, sawdust was not swelled. Compressed and uncompressed corn cob had different maximum swelling capacity with the value 1.62and 1.35, respectively. The swelling capacity of cottonseed hull was only 1.14. Rice bran and corn flour were also not swelled. The swelling capacity of wheat bran was only 1.03. All testing of raw materials, soybean had the maximum swelling capacity with value 1.75.2. In single corn cob particle size formulae, the mycelial growth rate and the mushroom yield reduced as the corn cob particle size decreased, while the lower particles will extend the cultivation time. In mixed corn cob particle sizes formulae, the mycelial growth rate and the mushroom yield increased as the corn cob particle size raising, there was no difference in the cultivation time. In uniform design corn cob particle size formulae, formula 5 had the highest yield and biological efficiency in all the 11 formulae. In a certain amount of corn cob, the formulae 2, 5, 7, 8, 10 had relatively few of small particle size of corn cob, the yield were also relatively high.3. The first formulae for single were screening the best nitrogen content suitable for mushroom growth, and further optimization of a single nitrogen source recipe testing to optimize the best nitrogen content. Finally, the mixed nitrogen formula were tested to screen the best formula when in the best nitrogen content. The results show that in the single nitrogen source substrate formulae experiment, when 30% of the amount of wheat bran added to the formula with nitrogen content 0.7933%, 40% of the amount of rice bran added to the formula with nitrogen content 0.8146%, 50% of the amount of corn flour added to the formula with nitrogen content 0.8036%, reach the maximum yield, respectively. Nitrogen source optimization formulation verified the above conclusions. Mixed nitrogen source substrate formulae were designed for the nitrogen content 0.80% to 0.81%. The formula 6 which was 29% sawdust, 29% corn cob, 16% wheat bran, 25% corn flour, 1% lime could reach the maximum yield and show a better commodity character.4. The acid value of rice bran increased as the storage time extended. There were no effect on mushroom growth and yield when the storage time was within 30 days. While much longer storage time with the acid value increasing, the mushroom yield decreased significantly and the cultivation time extended. When the rice bran acid value reached 118.11mgKOH/g oil, mushroom cultivation time extended 2 days, yield decreased by 35%. When the rice bran acid value reached 152.39mgKOH/g oil, the cultivation time of formula CK extended 2days, yield dereased by 26%; the cultivation time of formula rice bran extended the 4-day growth period, yield fell 68%.In this paper, physico-chemical properties of substrates to the industrial cultivation of Pleurotus eryngii were studied. Water holding capacity and imbibition rate of different raw materials were determined to provide the theoretical basis for designing formulae. Different corncob particle sizes of the substrate formulae were evaluated for the industrial scale cultivation of Pleurotus eryngii. The best nitrogen content suitable for mushroom growth was screened and the mixed nitrogen formula were tested to screen the best formula when in the best nitrogen content. The acid value of rice bran was also studied with the growth and yield of Pleurotus eryngii. All the reaches provided theoretical guidance for industrial cultivation.