| Aiming at the problem of random fertilization in apple orchard,the soil nutrient status in apple tree root area,apple tree growth,yield and quality of the four common methods of fertilization were compared and evaluated by field experiments,laboratory analysis,statistical analysis and evaluation methods to explore the optimal fertilization methods that can promote the growth of apple trees and cultivate soil fertility.It is of practical significance to promote the application of scientific and reasonable fertilization methods for apple trees.In this experiment,8 year old Fuji apple tree was selected as the research object.Field experiments were carried out with 4 treatments:broadcast fertilization,cirled furrow fertilization,radiate furrow fertilization and hole fertilization.The growth status,yield and quality of apple trees and soil nutrient status in root zone were investigated and compared to explore the suitable fertilization method.The main results were showed as follows:（1）Compared with other fertilization methods,hole fertilization was different in apple tree growth,yield and quality indexes,but the value was relatively high.The amplification in annual increment of trunk girth,length and diameter of new tip,yield and single fruit weight of hole fertiliazation were highest,which reached 59.58%,17.38%,12.84%,25.44%and 17.05%compared with other fertilization methods.Also,the fruit quality such as fruit shape index,anthocyanin content,hardness,soluble solid content,solid acid ratio and vitamin C content of hole fertilization were most improved by 1.20%,35.34%,8.82%,3.93%,12.78%and 24.86%respectively,and the titratable acid content was maximum reduced by 7.85%,comparing with other fertilization methods.Hole fertilization is the most effective way to promote the growth,yield and quality of apple.（2）The differences of soil chemical environmental conditions,nutrient status,enzyme activity and fertilizer supply of apple tree root zone were different,but the index values of hole fertilization was better than those of other fertilization methods.In addition to soil pH,the soil chemical environment and nutrient content of apple tree root area decreased with the increase of soil depth,and there was significant difference between the treatments in the 0-20cm soil layer and no significant difference in other soil layers.Compared with other fertilization methods,the maximum decrease of the soil conductivity and the most increase of organic matter content and p H of hole fertilization were 10.21%,3.22%and 20.05%,respectively.Also,hole fertilization promoted the content of soil nutrients in the experimental fertilization methods,in which the content of total nitrogen,available phosphorus and available potassium raised highest by 21.15%,21.24%,14.09%,respectively.The maximum amplification of hole fertilization in soil urease activity,catalase activity,saccharase activity and phosphatase activity were 53.64%,22.03%,42.07%and 15.15%,respectively,comparing with other fertilization methods.And the soil cation exchange capacity of hole fertiliazation was the highest,reached 16.62cmol·kg-1.Hole fertilization was the optimal fertilization method for controlling soil fertility in apple tree root zone under test conditions.（3）The main components and cluster analysis were used to quantify the growth of apple,soil nutrient status and their comprehensive evaluation of the root zone by different fertilization methods.The scores of hole fertilization were the highest,reached 2.75,3.73 and 4.75respectively.In conclusion,hole fertilization is superior to other fertilization methods in regulating apple tree growth,soil nutrient status in root zone and apple yield and quality,which recommends popularization and application to apple tree fertilization. |
PDF Full Text Request