Phytonematodes are small microscopic invertebrate animals living in the soil as parasites of many plants. Many plant-parasitic nematodes establish strong host-parasitic relations with major food, fruit, vegetable, and allied crops, resulting in a drastic yield loss globally. To control or manage these nematode menaces, farmers or growers use toxic fumigants, as well as non-fumigant chemical nematicides frequently. It is necessary to adopt eco-friendly products to tackle the nematode problem. This book explains the nature of nematodes, the role of organic methods and organic acids in nematode control, and the role of humic acid in agriculture, plant disease control, phytonematode control, nematode control. It also details the success of research trials on phytonematode control using humic acid on banana and citrus nematodes, as well as its compatibility with available biocontrol agents and its future prospects.