Scientific Reports (Jul 2025)

Influence of reduced nitrogen fertilizer combined with sheep manure on root-soil interaction in Korla fragrant pear orchards in xinjiang, China

  • Wei Li,
  • Xuemei Wang,
  • Linseng Yan,
  • Xiuxiu Liu,
  • Zhanyi He,
  • Kailong Wang,
  • Xing Shen,
  • Zhongping Chai

DOI
https://doi.org/10.1038/s41598-025-05509-9
Journal volume & issue
Vol. 15, no. 1
pp. 1 – 16

Abstract

Read online

Abstract The experiment aimed to address the issue of excessive nitrogen fertilizer application, explore an optimal model for combining reduced nitrogen fertilizer with organic fertilizer (sheep manure), and investigate their relationships with soil properties and pear tree physiology while assessing impacts on Korla fragrant pear yield. During the period from 2021 to 2023, 10-12-year-old pear trees at Awati Farm in Korla were selected for the study. Six treatments were established: no fertilization (CK), no nitrogen fertilizer application (N0), conventional fertilization (N), nitrogen fertilizer reduction treatment (N2 with a 20% reduction in nitrogen compared to conventional fertilization), and two combined treatments of reduced nitrogen fertilizer with two application gradients of organic fertilizer (F1 and F2, applying 22500 kg·hm− 2 and 33750 kg·hm− 2 of sheep manure, respectively), denoted as N2F1 and N2F2. Results showed that reducing nitrogen fertilizer application effect on soil physical and chemical properties and nutrient content, inhibited enzyme and root activities, increased root cortex thickness, and reduced the proportion of cellulose cell wall cells in phloem and xylem, as well as the total area of pear root vessels and slice area in the 20–40 cm soil layer. However, combining sheep manure improved these effects. Compared to full nitrogen application, N2F1 treatment significantly increased alkali-hydrolyzable nitrogen content in the 0–60 cm soil layer, soil organic matter in the 0–20 cm layer, total nitrogen in the 20–40 cm layer, protease activity in the 20–40 cm layer, and the number and proportion of phloem cellulose cell wall cells, while maintaining catalase and urease activities at levels similar to full nitrogen application. The N2F2 treatment significantly increased total nitrogen in the 0–20 cm soil layer, organic matter in the 40–60 cm layer, protease activity, root cortex thickness, and conduit and slice areas, with no significant change in root activity and total yield compared to full nitrogen application.

Keywords