Lopez root-knot nematode

Taxonomic position. Meloidogyne lopezi belongs to the phylum Nematoda, class Chromadorea, order Rhabditida, and the family Meloidogynidae. This nematode is a sedentary endoparasite, widely recognized for its ability to induce the formation of abnormal growths, or galls, on the roots of various host plants.

Host plants. The primary host for Meloidogyne lopezi is the potato plant. However, the pest is also known to attack other Solanaceae species, such as tomatoes and peppers. Its widespread distribution in specific agricultural regions necessitates constant monitoring, as it poses a significant threat to tuber quality and yield.

Biology and life cycle. The life cycle comprises an egg stage, four larval stages, and an adult stage. The second-stage juveniles are the primary infective stage; they penetrate the root epidermis. Once inside, the nematode loses mobility and establishes a feeding site, secreting specialized proteins that trigger hypertrophy and hyperplasia of root cells, resulting in galls.

Damage and economic significance. Infested plants exhibit stunted growth, yellowing (chlorosis), and wilting, especially under water stress. The characteristic galls on the roots restrict the uptake of water and nutrients, which significantly reduces the yield and the overall health of the crop. In severe infestations, total crop loss is a potential outcome.

Protection measures. Management strategies are centered on prevention, including the use of certified, nematode-free seed tubers and long-term crop rotation with non-host crops. Additionally, the integration of biological controls, such as beneficial fungi or bacteria, along with the application of approved nematicides and proper soil hygiene, constitutes an effective integrated pest management (IPM) program.