Effects Of Brackish Water Irrigation Andtrichoderma On Soil Properties Andphotosynthetic Performance Of Lyciumbarbarum In Coastal Saline Iand

The problems in the Yellow River Delta coastal saline-alkali land are low soil nutrients,poor air permeability and seepage capacity,and shortage of fresh water resources.In this study,the saline-alkali soil in the Yellow River Delta was used as the research object.Field experiments were conducted to study the effects of brackish water irrigation and Trichoderma on its soil properties,photosynthetic performance and output of Lycium barbarum.Establishing a method of adapting local brackish water irrigation to provide a theoretical basis for the local rational use of brackish water resources,Trichoderma to improve the soil and promote the growth of Lycium barbarum.The main results are as follows:(1)With the increase of brackish water irrigation,the change trend of soil water content is to increase first and then decrease,in which the soil water content of T4treatment is the largest.Brackish water irrigation has different effects on the conductivity of different soil layers.In the 0-40 cm soil layer,the soil conductivity is negatively correlated with the amount of irrigation water.The treatment with larger irrigation volume can reduce the pH value of saline-alkali soil,but it has no significant effect.The relative water content of the leaves of Lycium barbarum treated with T4was the highest.Na~+as the main ion causing salt damage,when subjected to saline-alkali stress,the Na~+content of the aerial parts of the plant increased.The Na~+content of treatment T4 was lower than other treatments,but the difference was not obvious.Photosynthesis is the basis of the production of Lycium barbarum.Compared with the control,brackish water irrigation can improve the photosynthetic capacity of the plant,and the photosynthetic capacity of the Lycium barbarum treated with T4increased significantly.Compared with the control,the yield of Lycium barbarum summer fruit and autumn fruit in T4 treatment increased significantly.Therefore,in this experiment,the irrigation volume of 1200 m~3is the most suitable for the growth of Lycium barbarum,with the highest yield.(2)The application of Trichoderma can improve the physical and chemical properties such as soil porosity,improve the soil water retention capacity,and the water content of T6 is significantly higher than that of other treatments.The conductivity of treatment T6 decreased significantly,showing a trend of decreasing first and then increasing.The pH value of the soil treated with T6 decreased significantly and reached its lowest value in July.Compared with the control,the contents of total carbon,total nitrogen,total phosphorus,nitrate nitrogen,nitrate nitrogen,ammonium nitrogen,available phosphorus and available potassium in the soil were significantly increased after applying the Trichoderma agent,and the total potassium content was also higher than Control,but the difference is not obvious.Compared with the control,the activity of soil urease,invertase,alkaline phosphatase,and cellulase were significantly improved after applying the Trichoderma fungus.The relative water content of the leaves of Lycium barbarum with Trichoderma was increased,the Na~+content of the leaves was reduced,the photosynthetic capacity was significantly improved,and the yield was significantly increased.Compared with the control,the yield of Lycium barbarum summer fruit and autumn fruit treated with T6 increased significantly.Therefore,from the test results,it can be concluded that Trichoderma improved the photosynthetic capacity of Lycium barbarum by improving the saline-alkali land,thereby increasing the yield of Lycium barbarum.(3)The interaction of brackish water irrigation and Trichoderma can significantly increase soil water content and reduce soil electrical conductivity,and its compound effect is superior to single treatment.The interaction of brackish water irrigation and Trichoderma can effectively reduce the soil pH,and its compound effect is inferior to Trichoderma treatment.The available nutrients in the soil were all treated with Trichoderma>brackish water irrigation and Trichoderma interaction>brackish water irrigation.The soil urease,invertase,alkaline phosphatase and cellulase activities were all present during the growth period of Lycium barbarum Interaction between brackish water irrigation and Trichoderma?Trichoderma treatment>Brackish water irrigation treatment.The photosynthetic capacity of Lycium barbarum in T2 was higher than that in T4 and lower than that in T6.Compared with the treatment T4,the relative water content of the leaves of the treatment T2 was significantly increased,and the Na~+content of the leaves was significantly reduced.There was no significant difference from the treatment T6.Compared with the treatment T4,the output of Lycium barbarum summer fruit and autumn fruit increased significantly;compared with the treatment T6,the output of Lycium barbarum summer fruit increased significantly and the fall fruit output decreased.Therefore,the interaction effect of brackish water irrigation and Trichoderma is significantly better than brackish water irrigation,slightly higher than Trichoderma treatment.In summary,in this study,the irrigated amount of 1200 m~3 is the most suitable for the growth of Lycium barbarum,with the highest yield.Trichoderma improves the photosynthetic capacity of Lycium barbarum and improves the output of Lycium barbarum by improving saline land.The interaction effect of the two is significantly better than brackish water irrigation,slightly higher than Trichoderma treatment.