Porphyridium lavender is an important natural enemy of plant parasitic nematodes. It is a kind of biocontrol bacteria and functional bacteria with promotion potential, which can control soil root knot nematodes and cyst nematodes. Porphyridium lavender can parasitize nematodes in a variety of ways. It can parasitize nematode eggs and cysts by physical means, and it can also produce metabolites paralyzed by the combined action of mechanical pressure and secreted extracellular enzymes during infection Nematodes, promote the colonization of fungi on nematode hosts and obtain nutrients, thereby playing a role in the prevention and control of nematodes. In addition, P. lavender secretes phytohormones during the growth process, which can promote and regulate the growth of nematode plants. Applying P. lavender around the plant roots can not only significantly inhibit nematode infections, and can promote the benign growth of plant roots and plant vegetative organs.