Research On Intelligent Drip Irrigation And Fertigation Technology For Precise Cultivation Of Malus 'Showtime' Seedlings

Ornamental crabapple?Malus spp.?is an important ornamental flower shrub and landscaping tree species in northern China.Fertilization and irrigation are the key to the cultivation of large crabapple seedlings.In order to improve the quality of large-scale seedlings,and to achieve the purpose of saving water and fertilizer,and improving the fertilizer fertilizer utilization efficiency,it is urgent to actively explore new ways to cultivate large-scale seedlings in gardens.In this experiment,2 to 3-year-old grafted seedlings Malus‘Showtime'was used as the test material,and an intelligent drip irrigation and fertilizer integrated test area was established at the Hezhuang Village Forest Farm Base in Shunyi District,Beijing.In this paper,drip irrigation and intelligent control system were used for studying irrigation and fertilization management process in plant's different growth periods,to improve water and nutrient use efficiency,saving water and fertilizer.The research results are as follows:1.The pattern of soil moisture movement along the rows of Malus‘Showtime'under drip irrigation were obtained.Using the drip irrigation pipe with the flow rate of 2 L/h,the distance between the drip heads of 50cm and continuous drip irrigation for 6 hours,the wet zone can be formed along the tree row within the range of 0-40cm of the main distribution soil layer of Malus ‘Showtime''s absorption root system.It can provide important parameters for the design of drip irrigation system and precise irrigation management.2.Annual variation law of soil water depletion of 2-year-old grafted seedlings Malus‘Showtime'during the growing season from April to October under the Intelligent drip irrigation has been studied and has provided a reference for guiding the precision irrigation in the future.3.The precision irrigation system of 3-year-old grafted seedlings Malus‘Showtime'under drip irrigation was proposed.The irrigation is conducted under the guidance of soil moisture content. Irrigation starts when the soil moisture content reaches 70%of the field water capacity.The single irrigation duration is 6h.The single irrigation capacity of 2500 plants of crabapple per hectare is 120m³/hm².The total annual irrigation capacity is 720m³/hm².The annual irrigation capacity is about 6times.4.The fine fertilization system of 3-year-old grafted seedlings Malus‘Showtime'under drip irrigation was proposed.Based on the absorption of nitrogen,phosphorus and potassium nutrients in the soil during the growing season,precise drip fertilization was carried out.The annual fertilization amount per stock was 118.76g N+P₂O₅+K₂O for crabapple.The average annual fertilization amount per stock through Intelligent drip irrigation system is 10 times in growing season.The results in this research will become the basis for the promotion and application of the drip irrigation and fertilization system by intelligent controlled in garden plant and maintenance of landscape in Beijing.The research results will have important reference significance for the construction of low-carbon and conservation-oriented garden cities in Beijing.