Turnip mosaic virus

Causative agent and disease type. Turnip mosaic virus (TuMV), classified within the genus Potyvirus, is a significant viral pathogen. It induces systemic infection in plants, leading to severe physiological dysfunction. As a plant virus, it is transmitted rather than caused by external environmental factors alone, making it difficult to manage once established in a field.

Affected crops. The virus has a wide host range, primarily targeting the Brassicaceae family. Major economic crops affected include turnips, cabbage, oilseed rape, mustard, broccoli, and arugula. Many ornamental plants and weeds can also harbor the virus, acting as a green bridge during the off-season or between planting cycles.

Symptoms and signs. Typical symptoms include localized chlorotic spots, mosaic patterns of yellow and green foliage, and leaf distortion. Infected plants often show stunted growth, crinkling of leaves, and sometimes necrotic lesions. In root crops, the development of the bulb or root is significantly hindered, resulting in reduced yields and poor quality.

Conditions for development and spread. The virus is transmitted primarily by aphids in a non-persistent manner. This means that the insect acquires the virus after a very brief feeding period and can transmit it almost immediately to a healthy plant. Environmental conditions that favor large aphid populations, such as mild springs and summers, significantly correlate with higher incidences of the virus in fields.

Harmfulness and protection measures. The damage caused by TuMV includes substantial yield loss and reduced commercial value of the produce. Management strategies emphasize prevention:

• using virus-free seeds and transplants;
• controlling aphid populations with effective insecticides;
• removing reservoir weed hosts from field margins;
• implementing proper crop rotation practices.