Downy Mildew Disease in Crops: A Comprehensive Review

Abstract

Downy mildew is one of the destructive plant diseases caused by obligate biotrophic oomycetes belonging primarily to the families Peronosporaceae and Albuginaceae. It affects a wide range of economically significant crops, including grapes, cucurbits, Brassicas, spinach, and ornamentals, leading to considerable yield and quality losses worldwide. This comprehensive review explains the taxonomy, life cycle, symptoms, and environmental conditions that favor the development of the disease. Emphasis is placed on the mechanism of underlying pathogenicity, symptoms, pathogens biology and recent advances in disease detection and diagnosis, in addition to current management strategies, including chemical control, cultural practices, and biological control. There is no proper method to eradicate 100% infection; resistant cultivars do not show full resistance to downy mildew, and fungicide applications can minimize the disease severity, but total eradication of the disease does not happen. Therefore, the development of organic fungicides is crucial for promoting environmentally friendly agriculture. Additionally, the use of biocontrol agents should be increased in the future to enhance disease control. The review also highlights future directions for sustainable downy mildew management in the context of climate change and integrated disease management systems. Recent advances emphasize the increasing role of biological control agents and genomics-driven breeding for durable resistance. Growers majorly face challenges like fungicide resistance, evolving pathogen populations, and limitations on resistance genes. Today’s need is to develop more resistant varieties by genomic editing to generate long-term downy mildew management. With that, downy management requires sustained research, integrated pest management, and grower education to adaptively combine cultural, chemical, and biological tools for sustainable crop protection. To overcome the problem it is mandatory that to develop more resistant varieties and to develop more environmentally friendly disease management strategies to maintain crop quality while maintaining quantity.