Pratylenchus

Pratylenchus is a group of very small worms called lesion nematodes. These tiny worms live inside plant roots and can harm many types of plants, especially in cooler places.

They mainly eat the soft parts of the root, which can make it harder for the plant to grow. Scientists study different kinds of Pratylenchus by looking closely at special parts of their bodies, like their mouth tools called stylets. These nematodes are important for scientists to learn about so we can find ways to protect plants.

Hosts and symptoms

Root lesion nematodes can infect many different plants. Pratylenchus penetrans affects over 350 kinds of plants, including important crops like soybeans, potatoes, corn, bananas, and wheat. These nematodes damage the roots, creating dark, dead spots called necrotic lesions. These lesions can allow harmful bacteria and fungi to enter the plant.

Above ground, infected plants may grow more slowly, look pale or chlorotic, and may wilt. Sometimes parts of a crop field can look patchy because some plants are healthier than others. This can lead to lower food production, so farmers watch for these problems.

Environment

Pratylenchus nematodes live in soil and are affected by things like moisture, minerals, temperature, and pH. They are often found in sandy soils and areas with weed. These nematodes can live in many places but like moist, temperate soils best. In very dry conditions, they stay inactive until it gets wet again and plants grow. They become most active when soil temperatures go above 68 °F (20 °C).

Management

One way to manage lesion nematodes is by using soil fumigation and nematicides. But this method does not always work and can be expensive. Another option is water immersion. This means putting infected plants in hot water for about 30 minutes. This can remove the nematodes without hurting the plant. This works well for P. coffeae.

Crop rotation can also help reduce nematodes in the soil. This works because different plants are affected by different Pratylenchus species. Choosing resistant plant varieties and cultivars is another useful strategy. This is the only current way to control P. vulnus.

Life cycle and pathology

Female lesion nematodes lay single eggs either inside plant roots or in the soil around them. They can make fertile eggs without needing males, a process called parthenogenesis. In many species of these nematodes, males are very uncommon.