Effects Of Different Strains And Cultivation Patterns On CO₂ Release Of Lentinula Edodes

Lentinula edodes is a large fungus with the same origin in food and medicine.It is not only a delicious food for people’s daily life,but also has high nutritional,medicinal and health care value.The total output in 2018 has exceeded 10 million tons,ranking first among all edible fungi.With the increase of the cultivation amount,the study on the heredity,breeding,cultivation pattern and cultivation pattern of L.edodes has been further developed.However,the research on the physiology of L.edodes cultivation is relatively less.The study on the environmental factors of L.edodes culture has been focused on the regulation of the environment such as temperature and ventilation.The study of specific environmental parameters such as light and air is lacking in the culture process.L.edodes consume O₂to provide energy for mycelium growth and fruiting body development and produce CO₂.Monitoring the CO₂release during the growth and development of L.edodes can provide theoretical support for in-depth research on the physiological and metabolic mechanism of L.edodes,guide the factory cultivation of L.edodes to a certain extent,and provide theoretical basis and scientific significance for the energy conservation and emission reduction of L.edodes.In this study,different cultivation patterns were used to culture and measure the amount of CO₂released from L.edodes"qihe 7",and the peak value of the two punctures produced by the artificial logs was studied,and the gradient test of the puncturing time and the number of punctures was designed.The CO₂release of factory cultivar"qihe 7","huxiang F2",long-aged strain"shenxiang 215"and high-temperature strain"931"were tested in the breathable bag pattern.The mycelia growth rate and CO₂release of"huxiang F2"and"shenxiang 215"were determined by selecting sawdust from different tree species to conduct a large test-tube mycelia culture test.Moreover,by conducting GO enrichment analysis and pathway enrichment analysis on transcriptome data of the puncture location of the artificial logs,differential expression genes affecting CO₂release were selected,and the metabolic mechanism of aerobic respiration was preliminarily determined by combining with the measurement of CO₂release changes.The main test results are as follows:1 The establishment of a method for the determination of CO₂release of L.edodesThis study directly aimed at the mycelia in the culture material to explore a simple and easy method to measure the CO₂release of L.edodes.The closed space modified by the sealed bag and the PVC sheet is used to monitor the change of CO₂concentration with the testo535 CO₂analyzer at an interval of 10min.According to the slope value of CO₂concentration,the molecular weight and molar volume of CO₂gas under standard conditions,the corresponding respiration rate and CO₂release per unit weight（kg）of culture material were calculated.2 Effects of cultivation patterns on CO₂release from L.edodes myceliumThe quality of carbon dioxide released from the"qihe 7"L.edodes strain per unit mass（kg）in different cultivation modes varies greatly.During the 90-day culture period,the overall amount of CO₂released under the artificial logs pattern showed a trend of first increase and then decrease.There are two peaks in the middle,which are caused by two punctures,the peaks are 9.35±0.13g/kg/day and 5.69±0.10g/kg/day respectively.Two peaks of CO₂release will also occur during the culture of the air filter bags.The highest values were 4.24±0.23g/kg/day and 4.80±0.16g/k/kg/day respectively,when the mycelium culture was full and at the color transition stage.After the artificial logs were punctured,the CO₂release amount began to be significantly higher than that of the air filter bags.A total of 273.62±0.25g was produced by the puncture artificial logs,and a total of 228.98±0.91g was released by the air filter bags.During the 90-day period of L.edodes cultivation,the puncture artificial logs released 1762.92k J of heat per kilogram of culture material,and the air filter bags released a total of 1482.30k J of heat per kilogram of culture material.3 Effect of puncture on CO₂release of L.edodesThe daily measurement of CO₂release from the cultivation process of"qihe 7"L.edodes mycelium showed that the first puncture operation was carried out on the34th day of mycelium culture,and the CO₂release increased rapidly from 4.37±0.13g to 9.35±0.13g and then gradually decreased,and the second puncture operation was performed on the 57th day of culture,and the CO₂release amount increased from4.16±0.14 g to 5.69±0.10 g.The the puncture artificial logs released 1762.92k J of heat per kilogram of culture material,and the non-punctured artificial logs released1608.53k J of heat per kilogram of culture material.4 Effects of puncture time of L.edodes on CO₂release of L.edodes myceliaThe effect of puncturing time on CO₂release of L.edodes was studied.The results of the first puncture time showed that the largest increase of CO₂was generated by the puncture on 38 days after the mycelium culture（the mycelium growth was nearly full）,with an increase of 3.70±0.54g/kg/day.The results of the second puncture time gradient showed that with the delay of the puncture time,there was no significant difference in the amount of CO₂increased by the puncture.5 Effects of the number of punctures on the CO₂release of L.edodes myceliumThe experiment studied the effect of different numbers of puncture holes on the CO₂release of L.edodes.The results showed that the CO₂release was highest with the number of puncture holes was 2 rows and 8 holes in the first puncture.the results of the second puncture showed no significant difference.6 The Effect of strain type on CO₂release of L.edodes myceliumDifferent types of L.edodes mycelium were cultured in air filter bags,and the effect of different strain types on CO₂release was investigated.The results showed that the long-term strains represented by"shenxiang 215"in the process of culture,the CO₂release only showed a peak of 7.12±0.58g on the 17th day of culture,The short-age strains"huxiang F2"and"qihe 7"both showed two peaks,both lower than"shenxiang 215".The age of the strains with high CO₂release at the coloration stage and the postripening stage was short.7 The effect of sawdust species on L.edodes mycelium and CO₂releaseThe effects of different sawdust species on the growth rate and CO₂release of mushroom mycelia were studied in the experiment of cultivating mushroom mycelia in a large test tube.The growth rates of"huxiang F2"and"shenxiang 215"were significantly the fastest in elm and small leaf hackberry,and the slowest in corn cob.The growth rates of mycelia in oak,apple and seabuckthorn were not significantly different.The change trend of CO₂release of the two strains in different sawdust media was consistent.The CO₂release of mycelia was the highest in phyllostachys and oak,followed by apple,elm and seabuckthorn.The CO₂release of mycelia was the lowest in apricot and corn cob.8 Transcriptome analysis results of puncture operationsThe GO enrichment analysis and KEGG Pathway analysis were performed from three aspects of molecular function MF,biological process BP,and cell component CC.The analysis results showed that the internal glucose metabolism was completely down-regulated after 2 hours of puncturing,mitochondrial activity increased,and oxidative phosphorylation increased.The level of redox has increased significantly.Gene expression related to thermogenesis was up-regulated,which was consistent with the heat release from the puncture.