rotröta

Ro tröta, or root rot, is a collective term for diseases that cause decay of plant roots and the root system. It reduces a plant’s ability to take up water and nutrients, leading to wilting, poor growth, yellowing, and often death. Root rot can affect many kinds of plants, including crops, fruit trees, ornamental plants, and turf. The disease can be caused by a variety of pathogens and may also be influenced by environmental stresses such as poor drainage, soil compaction, and prolonged wet conditions.

The pathogens most commonly involved are soil‑borne fungi and oomycetes, including Phytophthora spp., Pythium spp., Rhizoctonia solani, and Armillaria spp., as well as Verticillium spp. Bacteria and nematodes can predispose plants to rot by damaging roots, while abiotic factors like overwatering, drought, salinity, or excessive soil temperature can also induce symptoms similar to disease. The infection typically begins at the root tips or root crown and can spread into the feeder roots, causing darkening, softening, or disintegration of tissue.

Symptoms vary by host but often include wilting not relieved by irrigation, stunted growth, chlorosis, and a decline in plant vigor. On roots, rotted tissue is often brown to black and easily separated from firm, healthy tissue; older infections may leave a foul odor or visible mold.

Management focuses on prevention and suppression: ensure good drainage and soil structure, avoid wounding roots, use disease‑free planting material, rotate crops when feasible, sanitize tools, and maintain balanced irrigation. Chemical controls are limited and typically used as part of an integrated approach, with efficacy depending on the specific pathogen and crop.