Study On The Application Of Spent Mushroom Substrate In Matrix

China is the largest producer of edible fungi in the world,accounting for 70%of the world’s output.The edible fungi industry has become the fifth largest agricultural industry in China.As the main waste of edible mushroom industry,the output of spent mushroom substrate(SMS)is five times of that of edible mushroom,and the total output exceeds 100 million tons every year.The improper disposal of SMS will cause great pressure on the environment,and the rational utilization of SMS will bring new benefits to the industry.Because of its excellent substrate properties,the substrate utilization of SMS has become one of the main utilization technologies.However,due to the differences in physical and chemical properties of different SMS,it is difficult to systematically study the application effect of SMS in the field of substrate.Therefore,according to the characteristics of SMS and crop needs,developing special substrates,and studying the application rules,establishing the relationship between the characteristics of SMS and crop growth status are the main direction of research on the utilization of waste matrix.In this study,Yunyan 87 tobacco and Dendrobium huoshanense,two cash crops planted on a large scale in southern China,were used as research objects,SMS of Pleurotus vulgaris as test materials,peat,vermiculite,perlite,earthworm dung and bark as ingredients,and hole tray experiments were used to study the suitable formulation of tobacco seedling and Dendrobium cultivation substrate respectively.Physicochemical properties such as pH,organic carbon,nitrogen and phosphorus were studied to study the effects of formulation treatment on substrate characteristics.By measuring plant height,plant weight,root morphological characteristics,soluble sugar,soluble protein,root activity and other growth physiological indicators,the response of each crop to substrate indicators was analyzed,the principle of different formulations affecting crop growth was clari fied,and the adjustment of SMS matrix was put forward.Control key factors.The main results are as follows:(1)In tobacco seedling cultivation,the plant height,root activity and seedling index of tobacco treated of tobacco with T5(wormcast:SMS:vermiculite:perlite=1:1:1:1)were 50.1%,23.9%and 41.6%higher than those of CK(peat:vermiculite:earthworm dung=2:1:1),and the growth properties were significantly better than those of other groups,which was the suitable tobacco cultivation substrate.Through correlation analysis and redundancy analysis,it was concluded that the electrical conductivity,organic carbon and available iron content of matrix were negatively correlated with the physiological indexes of tobacco growth,and the bulk density,total phosphorus and total potassium of matrix were positively correlated with the physiolocgical indexes of tobacco growth.Among them,the electrical conductivity and total phosphorus of matrix were the most important factors affecting the growth of tobacco seedlings.Compared with the other groups,T5 treatment had the advantages of lower level conductivity(568.20 μS·cm-1)and higher total phosphorus content(6.09 mg·g-1),so it had the best seedling-raising effect.SMS generally has high conductivity(0.4 mS·cm-1～3.4 mS·cm-1),but it has suitable pore structure(more than 70%)and total phosphorus content(about 10 mg·g-1).If the conductivity can be regulated and its advantages can be brought into play,it is also feasible using for tobacco seedling cultivation.(2)In the cultivation of Dendrobium huoshanensis,the results showed that 25%decomposed SMS mixed in bark or 25%undeco,posed SMS mixed in bark were the most suitable substrate for Dendrobium huoshanensis cultivation.Compared with pure bark matrix,the growth indexes of Dendrobium huoshanensis had no significant difference in statistics.Redundancy analysis showed that the matrix pH,conductivity,water-holding porosity were negatively correlated with Dendrobium plant weight,root number,root length and other growth indicators,while the matrix permeability porosity was positively correlated.The SMS of Xiuzhen mushroom has the characteristics of high pH,high conductivity,high water holding porosity and slightly low air permeability.Although it has no advantages in Dendrobium cultivation,this experiment shows that proper addition of SMS in bark has no obvious effect on the growth of Dendrobium,and the treatment is simple,which may reduce the production cost,and can be added in a proper amount in production.In addition,the undecomposed SMS has higher conductivity and lower permeability than the decomposed SMS,but it has the advantages of simplified process and higher economic benefits.The experiment proves that it is also feasible to cultivate Dendrobium.In summary,spent mushroom substrate(SMS)has good application effect in seedling-raising and cultivation substrates.Its high conductivity decides that it is not suitable for overuse of substrates,but its unique role in controlling water and gas retention capacity of substrates and regulating nutrient structure of substrates,low cost,has great potential for utilization in the direction of substrates.In practical application,electrical conductivity should be regulated by adding other materials according to crop tolerance.This study provides an example and theoretical basis for the utilization of mushroom residue in tobacco seedling matrix and Dendrobium cultivation matrix,and has important significance for the application of solid waste residue in the field of substrate.