Vol. 65 No. 2 (2026)
Articles

Integrated management of citrus gummosis (Phytophthora spp.) in semi-arid Iran: combined effects of chemical, cultural, and nutritional strategies

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  • Seyed Ali Akbar BAGHERIAN,
  • Behzad HAJIEGHRARI
Seyed Ali Akbar BAGHERIAN
Department of Horticultural Science, College of Agriculture, Jahrom University, Jahrom, Iran
Behzad HAJIEGHRARI
Department of Agricultural Biotechnology, College of Agriculture, Jahrom University, Jahrom, Iran
DOI: https://doi.org/10.36253/phyto-17259

Published 2026-09-10

Keywords

  • Soil waterlogging,
  • orchard sanitation,
  • fungicide management,
  • tree recovery,
  • soil aeration

How to Cite

[1]
S. A. A. BAGHERIAN and B. HAJIEGHRARI, “Integrated management of citrus gummosis (Phytophthora spp.) in semi-arid Iran: combined effects of chemical, cultural, and nutritional strategies”, Phytopathol. Mediterr., vol. 65, no. 2, pp. 309–317, Sep. 2026.

Copyright (c) 2026 Seyed Ali Akbar BAGHERIAN, Behzad HAJIEGHRARI

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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Abstract

Citrus gummosis (citrus foot rot), commonly associated with Phytophthora spp. in citrus orchards, significantly limits citrus production in semi-arid regions, causing trunk cankers, gum exudation, and substantial yield losses. Field efficacy of an integrated disease management (IDM) programme combining chemical, cultural, and nutritional strategies was evaluated for reducing disease incidence and enhancing tree vigour and fruit yield. Over two years, trials were carried out across 12 commercial orchards. Cultural measures included soil aeration by collar excavation, conversion to dual-line drip irrigation, and application of well-decomposed organic manure as a surface mulch within the drip line. Assessments included disease incidence, severity of gum exudation, host plant vegetative growth, and fruit yields. Six months after implementation, disease incidence decreased from 65% at baseline to 20 ± 3% in the surviving IDM-treated trees, compared with 65 ± 5% in the untreated controls (GLMM treatment effect: χ²(1) = 48.3, P < 0.001). IDM-treated trees exhibited a 40% increase in shoot length and a 38% increase in trunk-diameter increment, while mean fruit yield increased from 15 ± 2 to 25 ± 3 kg tree⁻¹, corresponding to a 66.7% increase (P < 0.001). The IDM programme also improved tree recovery relative to the untreated controls in the semi-arid orchards evaluated. Although this IDM package gave short-term efficacy under the semi-arid conditions evaluated, its regional transferability should be validated through multi-location trials before broad implementation. Because Phytophthora pathogens were not isolated and identified, these results came from management of a macroscopic gummosis symptom complex, so long-term economic analyses and robust epidemiological monitoring are required to substantiate robust field recommendations.

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