Effects Of Microbacterium Testaceum On The Growth And Soil Properties Of Camellia Oleifera,Pinus Elliottii And Ailanthus Altissima

With the continuous development of agriculture and forestry,as well as the improvement of human production and living standard,a large number of chemical fertilizers and pesticides have been used in agricultural and forestry production.The excessive application of chemical fertilizers and pesticides has caused serious threat to the ecological environment.At the same time,the soil is seriously degraded,which affect the trees growth.Therefore,it has become a research hot spot to development fertilizer-efficient and polluting-free microbial fertilizers.The substrate and microbial inoculants of microbial fertilizers come from natural environment,do not pollute to the environment,and can improve soil properties and promote plant growth.In this research,the effects of bacterial fertilizer on tree growth status,physiological,and biochemical indexes and soil properties of Camellia oleifera,Pinus elliottii and Ailanthus altissima was studied to reveal the mechanism of bacterial fertilizer on forest growth and soil improvement,which provided scientific basis for the large-scale application of bacterial fertilizer on Camellia oleifera,Pinus elliottii and Ailanthus ailanthus.The main results are as follows:(1)Bacterial fertilizer had certain effects on the growth and soil properties of annual,triennial Camellia oleifera.Bacterial fertilizer significantly increased the height and ground diameter of Camellia oleifera.The content of K,P,Ca,Mg,Cu and Fe in the leaves of Camellia oleifera was significantly increased,among them,the content of Ca,Mg and Cu in the leaves of triennial Camellia oleifera with bacteria fertilizer treatment was 1.57,1.90 and1.88 times as that in the blank control,and the contents of chlorophyll a,chlorophyll b and total chlorophyll were also increased significantly,which was 2.19,1.89 and 2.11 times that of the blank control respectively.The contents of soluble sugar,soluble protein,the activity of superoxide dismutase and peroxidase were also increased significantly.Bacterial fertilizers also distinctly promoted the physical and chemical properties of Camellia oleifera.Bacterial fertilizer obviously increased the soil capillary porosity,non-capillary porosity and maximumwater holding capacity of the annual,and the triennial Camellia oleifera,decreased the soil density,and significantly accelerated the content of the soil organic matter,hydrolytic nitrogen,available phosphorus and available potassium,and the contents of hydrolytic nitrogen and available phosphorus in triennial Camellia oleifera increased by 63.69% and 66.36%respectively.The activity of soil catalase,urease,invertase and phosphatase were also significantly accelerated.At the same time,the metabolic activity and diversity index,richness index,evenness index and dominance index of soil microbial community were improved,and the utilization of carbohydrates,carboxylic acids,amino acids,phenolic acids,polymers and amines was improved significantly as well.(2)Bacterial fertilizer significantly increased the relative growth of plant height and ground diameter of Pinus elliottii,which were 1.53 and 1.26 times of the control respectively.Bacterial fertilizers also distinctly improved the physical and chemical properties of Pinus elliottii.Bacterial fertilizer significantly increased the soil capillary porosity,non-capillary porosity and maximum water holding capacity of Pinus elliottii,while reduced the soil density,but the difference was not significant.At the same time,bacterial fertilizer significantly increased the content of the soil organic matter,available phosphorus and available potassium,which were 1.40,1.35 and 1.60 times of control respectively.Meanwhile,the activity of soil catalase,urease,invertase and phosphatase,and the content of hydrolytic nitrogen was also increased,but the difference was not significant.Bacterial fertilizers also significantly promoted the metabolic activity of soil microbial communities,diversity index and the utilization ability of six types of carbon sources.(3)Bacterial fertilizer significantly improved the contents of K,P,Ca,Mg,chlorophyll a,chlorophyll b,total chlorophyll and the activity of antioxidant enzyme SOD and POD in the leaves of Ailanthus altissima,and significantly reduced the content of Na+,Na+/K+,proline and malondialdehyde,and also increased the resistance of Ailanthus Ailanthus to saline alkali stress,thus the height and ground diameter of the plant were promoted.Bacterial fertilizer significantly reduced soil density and increased capillary porosity,non-capillary porosity and maximum water holding capacity in saline alkali land.Bacterial fertilizer also significantlypromoted soil organic matter,hydrolytic nitrogen,available phosphorus and available potassium conten,which were increased by 58.47%,61.84%,33.43% and 33.39% respectively.The activity of soil catalase,urease,invertase and phosphatase were also significantly promoted by bacterial fertilizer.Meanwhile,the microbial community diversity and metabolic activity of bacterial fertilizer treatment increased.