Life/disease Cycle
Root lesion nematodes are migratory endoparasites. This means that they usually feed on the roots internally versus ectoparasites that feed on the roots externally. The migratory endoparasite enters the root by puncturing a hole in an outside cell with its stylet. Once the nematode has access to the inside of the cell, it continues to migrate from one cell to the next feeding along its way. As it moves through the cells, and takes nutrients from them, the cells are left with tiny lesions that eventually become necrotic as the root begins to decay. As the nematode feeds on the cells in order get nutrients, the metacarpal pump (a part of a nematode) begins to “pump” nutrients are ingested into the nematode. Over the course of feeding on a specific root, female nematodes lay single eggs that can hatch in the root (or if the egg was laid in the soil, it hatches in the soil) and the process begins again with the juvenile nematode. Pratylenchus does not need both male and female to reproduce; in fact the females can and do lay eggs without the presence of males. For some species, the number of females drastically outnumbers the number of males.
Read more about this topic: Pratylenchus
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