Effects Of Interplanted Rapes Planting In Mountain Dryland Orchards On Soil Moisture And Nutrients And Fruit Tree Growth And Yield

The loess Plateau region is suitable for the growth of apple due to its high altitude,sufficient sunlight and large temperature difference between day and night.However,the lack of water and nutrients has always affected the growth,yield and quality of apple in mountain areas.Therefore,it is very important to select appropriate orchard management measures to improve the water and nutrient supply capacity of dry orchard.Therefore,this research choose hilly-gully loess plateau dry farming orchards,Trials began in 2018,it adopt dual cover(fruit trees root + rapes of fruit trees to cover cloth cover)of the orchard management mode,choose three different varieties of rape(napus rape Shaanyou 2013,spring cabbage type rape Haoyou 21 and strong winter cabbage type rape Yanyou 2)compared with traditional clear farming system.To explore the effects of different modes of mulching and returning green fertilizer on soil moisture and nutrients,fruit yield and quality and tree growth and development in upland orchard,and to provide theoretical support for the establishment of suitable rape variety mulching mode in upland orchard.The main results are as follows:(1)Cabbage type rape had the largest stem and leaf dry weight,the strong winter cabbage type rape had the smallest stem and leaf dry weight,the strong winter cabbage rapeseed had the largest root/stem,taproot thickness and taproot length,while the spring cabbage type rape had the smallest root/stem,taproot thickness and taproot length.It can be seen from the soil moisture content of three years that the soil moisture content under the cover of strong winter cabbage type rape is better than that of other treatments and CK at a distance of 100 cm,150 cm and 200 cm from the trunk,while the cabbage type rape showed lower soil moisture content than CK in the previous test.(2)Under the dual mulching mode,the contents of soil organic matter,total nitrogen,total phosphorus,available phosphorus,alkali-hydrolyzable nitrogen and available potassium of inter-row rapeseed planting were increased to a certain extent compared with CK,indicating that inter-row rapeseed planting could effectively improve the soil nutrient content of orchard.The effects of different rape mulching patterns on soil nutrients were compared,and the strong winter cabbage rape and spring cabbage rape mulching patterns were the best.(3)Rape mulching could increase the louver thickness,chlorophyll content and leaf area of apple tree leaves.Among them,planting strong winter brassica napus had the best effect on improving leaf thickness and leaf area of apple trees.The chlorophyll content of apple tree leaves increased the most when planting spring cabbage rape.Rape mulching could also increase the radius of crown,height and ground diameter of apple tree,and the effect of spring cabbage rape was the best.Compared with CK,the yield and quality of rapeseed could be improved to a certain extent.In conclusion,according to the measurement of soil moisture content,soil nutrient content and the effect on the growth and development of apple trees,it was found that the inter-row covering of strong winter cabbage rape was the best in upland orchard,followed by spring cabbage rape.Therefore,inter-row planting of strong winter cabbage type rape could be promoted and applied as a dual mulching mode in upland apple orchard to effectively improve soil fertility and apple quality in apple orchard.