Effects of Regulated Deficit Irrigation on Leaf Nutrients, Enzyme Activities, and Root Zone Soil Nutrients during Fruit Expansion and Coloration-Sugar Accumulation Stages of Citrus in Western Hubei Province

• Published in: Shui tu bao chi xue bao Vol. 39; no. 2; pp. 238 - 249
• Main Authors: ZHONG Yun, HUANG Zhikun, ZHU Shijiang, HAO Kun, ZHU Zirong, ZHANG Wei, CHEN Hongde
• Format: Journal Article
• Language: Chinese
• Published: Editorial Department of Journal of Soil and Water Conservation 01.04.2025
• Subjects: citrus; leaf nutrients; leaf protective enzyme activities; regulated deficit irrigation; soil nutrients
• ISSN: 1009-2242
• DOI: 10.13870/j.cnki.stbcxb.2025.02.036

［Objective］ This study investigated the effects of regulated deficit irrigation on leaf nutrient levels (nitrogen, phosphorus, and potassium), enzyme activities (superoxide dismutase, peroxidase, and catalase), and root-zone soil nutrients (nitrate-nitrogen, available phosphorus, and available potassium) during the fruit expansion (Ⅲ) and coloration-sugar accumulation stages (Ⅳ) of citrus in western Hubei Province. ［Methods］ Six-year-old“Ehime 28” citrus trees in the western Hubei region were selected as the research subjects. Full irrigation served as the control (CK: daily irrigation volumes of 4.0 and 2.5 L during the fruit expansion stage (Stage Ⅲ) and coloration-sugar accumulation stage (Stage Ⅳ), respectively). Four deficit irrigation treatments were applied during both Stage Ⅲ and Stage Ⅳ, including mild deficit (LD: 70% of CK), moderate deficit 1 (MD1: 55% of CK), moderate deficit 2 (MD2: 40% of CK), and severe deficit (SD: 30% of CK). The aim was to explore the response patterns of soil nutrients, ci