Citrus Gummosis: A Global Threat to Citrus Production and Quality-Distribution, Diagnosis, and Management Strategies

Yasir Iftikhar, Mustansar Mubeen, Ashara Sajid, Aqleem Abbas, Muhammad Ahmad Zeshan, Usman Saleem, Komal Ambreen


Citrus, the most economically important fruit crop worldwide, faces numerous challenges from various diseases caused by fungi, bacteria, viruses, nematodes, and spiroplasma. Among these, gummosis, primarily induced by Phytophthora spp., poses a significant threat to citrus orchards, leading to substantial yield losses. Phytophthora spp., P. citrophthora and P. nicotianae, are the most prevalent pathogens responsible for gummosis in citrus-growing regions worldwide. The symptoms of gummosis, characterized by gummy substance formation and rotting roots, are described in detail, along with observations of gum exudation, cracks, cankers, and necrotic lesions on various parts of the plant. The review explores the historical background of citrus gummosis, tracing its initial outbreaks and identifying Phytophthora spp., as the causal agent. Understanding the epidemiology and ecology of gummosis is crucial for effective disease management. Factors influencing disease development, such as humidity, temperature, soil moisture, and rainfall, are discussed based on studies conducted in different regions. This highlights the pathogen’s life cycle, emphasizing the importance of soil contact and water in the dispersal of Phytophthora spp. The comprehensive review provides valuable insights into the current knowledge of citrus gummosis, facilitating further research and development of sustainable management strategies to combat this devastating disease.


Citrus; Phytophthora spp.; Gummosis; Symptoms; Management

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