Objective  The application effects of intercropping green manure and water and fertilizer integration were studied in apple orchards.

  Method  The effects of green manure of Vicia villosa Roth and drip irrigation equipment on soil fertility and fruit quality in apple orchards were tested from 2018 to 2020. Five treatments, including conventional fertilization and natural grass (CF), drip irrigation and conventional fertilization and natural grass (SF), conventional fertilization and green manure (GF), drip irrigation and conventional fertilization and green manure (SGF), and drip irrigation and topdressing with nitrogen, phosphorus and potassium applying 20% less than conventional fertilization and green manure (80%SGF), were designed to carry out water and fertilizer experiment in apple orchard.

  Result  The 2-year results showed that among all the treatments, SGF treatment soil had the most microorganisms, the highest soil nutrient contents and the best apple fruit quality. Compared with CF treatment, the contents of soil alkali-hydrolyzed nitrogen and available potassium in SF treatment increased by 8.46% and 10.06%, the contents of soluble solid and VC in apple increased by 11.01% and 4.37%, the number of soil actinomyces, urease and phosphatase activities significantly increased in SF treatment, and the contents of soil alkali-hydrolyzed nitrogen in GF treatment increased by 8.09%. The contents of soluble solid and VC in apple increased by 14.86% and 9.25%, the number of soil microorganisms and the activities of soil urease and phosphatase increased significantly. Compared with SF treatment, soil organic matter, alkali-hydrolyzable nitrogen and available phosphorus contents in SGF treatment were significantly increased, soluble solid and VC contents in apple were increased by 7.74% and 8.80% on average, and titratable acid contents were decreased by 11.12%. Compared with GF treatment, the contents of alkali-hydrolyzable nitrogen, available phosphorus and available potassium in SGF treatment were significantly increased, while the contents of soluble solid and VC were significantly increased.

  Conclusion  The application of green manure intercropping and water and fertilizer integration technology in fruit production could significantly improve soil fertility index and apple fruit quality, and the treatment of drip irrigation and conventional fertilization and green manure intercropping had the best effect.