| Aiming at the problems of lack of microbial treatment and restoration technology and unclear mechanism in saline-alkali land at the eastern foothills of Helan Mountain in Ningxia,the wine grape variety "Merlot",which is widely planted at the foothills of Helan Mountain Mountain,was used as the test material.Treatment of chemical fertilizers,bio-organic fertilizers,powder microbial inoculants,and liquid microbial improvers.Research and analyze the effects of microbial fertilizers on soil physicochemical and biological properties and fruit growth,and screen a series of functional microbial fertilizer products suitable for forest fruit planting in saline-alkali land,in order to provide a theoretical basis for demonstration and promotion on saline-alkali land in typical counties.The main conclusions are as follows:(1)The main ion composition of soil in the fertilization period belongs to the Na++K+-Cl-+SO42" type,and in the harvest period,it belongs to the Ca2++Mg2+-Cl-+SO42-type.There is a significant positive correlation,which can well reflect the change of soil salinity content.Bio-organic fertilizer can significantly reduce soil Na+content,pH value and total salt content,and has a significant effect on reducing soil salinization and improving soil physical and chemical properties(p<0.05).(2)Microbial fertilizers can effectively increase the content of soil available nutrients,among which bio-organic fertilizer treatment has the best effect on improving soil nutrient content.The contents of soil organic matter,alkali-hydrolyzed nitrogen,available potassium and available phosphorus increased significantly under the treatment of bio-organic fertilizer.And for the three microbial fertilizers,the soil nutrient content in the non-inactivation treatment was significantly higher than that in the inactivation treatment.Microbial fertilizer can effectively improve soil enzyme activity.In the 0～20cm soil layer during the harvest period,the soil invertase activity of bio-organic fertilizer treatment is the highest;the soil urease activity of bio-organic fertilizer and powder microbial inoculum treatment is higher.In the 20～40cm soil layer,the soil sucrase activity of powder microbial inoculum treatment was the highest,which was 15.4 mg/g·d;the soil urease activity of bio-organic fertilizer treatment was the highest,which was 11.6 mg/g·d.(3)The dominant phyla of soil bacteria in each fertilization treatment in different periods were Proteobacteria,Acidobacteria,Bacteroidetes,and Actinomycetes,and the dominant bacterial genera were Nitrospirulina,RB41,MND1,and Sphingomonas.The soil bacterial diversity index of the fertilization treatment was significantly higher than that of the control,and the community structure was significantly different.Through redundancy analysis and correlation analysis,it was found that soil organic matter,alkaline hydrolyzable nitrogen,pH value and total salt content were the main factors affecting the diversity of soil bacterial communities,of which organic matter was the most important driving factor.Microbial fertilizers can increase soil nutrient content to varying degrees,reduce soil pH,and total salt content,and bio-organic fertilizers have the most significant overall effect.(4)Microbial fertilizers have a good effect on the improvement of reducing sugar content in fruits,among which inactivation and inactivation of bio-organic fertilizers and liquid microbial modifiers are higher.The soluble solid content of grapes treated with bio-organic fertilizer was the highest,which was 23.0%.Inactivated and inactivated bio-organic fertilizer treatments had the highest sugar-acid ratio,which increased by 9.3%and 9.8%compared with the control.The single-grain weight of the fruit treated with powder microbial inoculum was the highest,which was 2.3 g.The 100-grain weight of the fruit treated with bio-organic fertilizer was the highest,which was 195.2g.The yield of conventional fertilizer treatment was the highest,reaching 438.3kg/667m2.The net photosynthetic rate of bio-organic fertilizer and powder microbial inoculum treatment was higher;the leaf transpiration rate of liquid microbial amendment treatment was the highest,which was 7.1mmol/m2·s;the treatment of bio-organic fertilizer with higher net photosynthetic rate also had higher transpiration rate,At the same time,its stomatal conductance is also the highest,which is 217.0mol/m 2·s.The relative content of chlorophyll in the biological organic fertilizer treatment was the highest,which was 42.4(SPAD value).Under the treatment of bio-organic fertilizer,soil pH value,total salt and sodium ion content were significantly reduced,and soil organic matter,available nutrient content and enzyme activity were significantly increased,which could effectively improve soil salinization and improve soil fertility.At the same time,soil under bio-organic fertilizer treatment The bacterial community diversity index was significantly higher and the number of species was also higher.The sugar content and 100-grain weight of wine grapes were the highest among all treatments,and the net photosynthesis and chlorophyll content were the highest,which could increase soil microbial community diversity,improve quality and Promote photosynthesis in plants.The three microbial fertilizers have good effects on improving soil salinity,improving soil fertility and microbial community diversity,and on agronomic traits of wine grapes.On the whole,bio-organic fertilizer has the best effect. |
