Reuse Of Fungus Residue Rich In Camellia Oleifera Sawdust In The Container Seedling Substrate Of Camellia Oleifera

Camellia oleifera is an important woody oil tree species in China,which has made great contributions to national food and oil security.In recent years,China has attached great importance to the development of Camellia oleifera industry.Cultivating high-quality seedlings is the basis for the development of Camellia oleifera industry,and the seedling substrate has an important impact on the quality of seedlings.At present,there are some problems such as high cost,unstable physical and chemical properties in the traditional seedling substrate,peat with the highest proportion of substrate is also non-renewable.Finding new high-quality alternatives is a current hot spot.A large number of residues were produced during the transformation of low-yield Camellia oleifera forest.Edible mushroom residue contains rich fungal polysaccharides,amino acids,proteins,and minerals.The scientific and efficient utilization of edible mushroom residue is of great significance for protecting the environment,promoting the development of the edible mushroom industry,and promoting the transformation of circular economy.Research has shown that edible mushroom residue has excellent physical and chemical properties,rich nutrition,and contains a large amount of antibacterial substances,making it an ideal material to replace peat in preparing seedling substrates.Therefore,this paper uses Camellia oleifera sawdust residue as the seedling matrix,and uses the 3-year-old Camellia oleifera seedling of the improved variety of Camellia oleifera’Huashuo’ as the research material.The single-factor controlled pot experiment is adopted.A total of 4 Camellia oleifera sawdust residue application gradients of 0%,25%,50%,75%(CK,T1,T2,T3)are mixed with the conventional matrix respectively,the effects of different proportions of Camellia oleifera sawdust fungus residue on the physical and chemical properties,enzyme activity,microorganisms and the growth of Camellia oleifera were studied in order to provide theoretical basis for the reuse of Camellia oleifera sawdust fungus residue.The main results of this study are as follows:(1)The physical and chemical properties of Camellia oleifera seedling substrate under different application rates of fungus residue were determined.The results showed that there were significant differences in the physical and chemical properties of the substrate under different application rates of Camellia oleifera sawdust fungus residue,and the physical and chemical properties of treatment T2 were significantly better than other treatments.With the increase of the application amount of Camellia oleifera sawdust fungus residue,the pH value,conductivity,total porosity,aeration porosity and air-water ratio of the substrate were significantly increased,the water-holding porosity and bulk density were significantly decreased,the content of total nitrogen,total phosphorus,hydrolytic nitrogen,available phosphorus and available potassium in the nutrient elements increased,and the content of total potassium decreased.The addition of 50%Camllia oleifera sawdust fungus residue in the Camellia oleifera seedling substrate can effectively improve the physical and chemical properties of the substrate and improve the fertility of the substrate.(2)The enzyme activities of the Camellia oleifera seedling substrate were measured under different application rates of fungus residue.The results showed that the addition of Camellia oleifera sawdust fungus residue in the Camellia oleifera seedling substrate had a significant impact on the activities of catalase(CAT),sucrase(SC),urease(UE)and acid phosphatase(ACP)in the substrate,and the activities of the four enzymes above all increased with the increase of the application rate of Camellia oleifera sawdust fungus residue.(3)The number and diversity of microorganisms in the matrix of Camellia oleifera seedlings under different application rates of microbial residues were determined.The results showed that the microbial residues of Camellia oleifera sawdust can help to increase the biomass of bacteria and fungi in the matrix and reduce the diversity of bacteria and fungi.(4)The plant height,ground diameter,and crown diameter of Camellia oleifera.under different application rates of fungus residue were measured.The results showed that the addition of Camellia oleifera sawdust fungus residue to the Camellia oleifera seedling substrate had no significant impact on the ground diameter of Camellia oleifera;The plant height,eastern and western crown widths,biomass,and root indexes of Camellia oleifera were significantly increased compared to the control group when the application rate of Camellia oleifera sawdust fungus residue in the seedling substrate reached 50%(T2),while the growth of Camellia oleifera was inhibited when the application rate reached 75%(T3).