0 Sunil Singh 2012 Australasian Plant Pathology <p>Root-Knot nematodes (RKN) are one of the most damaging groups of plant-parasitic nematodes capable of attacking a wide range of crop plants as well as many weed species. With damage thresholds of 1- 2 nematode(s) per gram of soil, <em>M. incognita</em> is one of the most destructive species worldwide. The effects of RKN infestation include reduction in number of leaves, decrease in photosynthetic ability, reduction in flowering, and decrease in fruit production, all of which are very similar to symptoms of nutrient deficiency. In addition to direct damage, <em>M. incognita</em> is able to form disease complexes with fungal pathogens such as <em>Fusarium</em> sp. and can exist in mixed populations with other <em>Meloidogyne </em>sp.</p>