Plant-parasitic nematodes pose a significant threat to crop cultivation, with the genus Tylenchulus being the major culprit, notably damaging citrus crops. Discovered in 1913 by J.R. Hodges in California, Tylenchulus harmed orange tree roots, a connection later confirmed by E.E. Thomas. Named by Nathan Cobb, Tylenchulus semipenetrans is economically crucial, with its eggs surviving in the soil for up to 9 years without a host. Three primary biotypes—Citreus, Mediterranean, and Poncirus—affect citrus, with the latter primarily in California, reproducing grapes. The Mediterranean type is widespread in various regions, reproducing olives and other hosts through parthenogenesis. Citrus nematodes pose a serious threat to citrus trees, manifesting visible signs such as inhibited growth, leaf yellowing, and small fruit. Below ground, diseased roots become thicker, darker, and deformed due to nematodes creating gelatinous matrices that attract dirt particles. This compromises the ability of the root system to absorb sufficient water and nutrients, which results in stunted growth, dieback, and foliage yellowing. High nematode populations lead to nurse cell formation, causing nutrient depletion in plants. Adverse effects include compromised root development and the decomposition of young roots. In summary, citrus nematodes severely affect the overall health and vitality of citrus trees. Regular measures are essential to control nematode populations in citrus groves because complete eradication is challenging once established. Optimal prevention involves using certified trees from nurseries, especially new plants. Employing clean equipment further reduces the risk of virgin or uncontaminated soil. Although certified trees mitigate damage in low-nematode soils, their effectiveness diminishes in high-nematode areas. Effective prevention includes regular cleaning equipment to remove dirt and root debris and to prevent nematode spread between groves. Overall, consistent use of certified trees and meticulous equipment hygiene are crucial for managing nematode issues in citrus groves.