Parasitic root-knot nematode

Systematic position: Meloidogyne paranaensis belongs to the phylum Nematoda, class Chromadorea, order Rhabditida, and family Meloidogynidae. This species is categorized as a gall-forming nematode, known for its high level of specialization and severe impact on agricultural production in subtropical regions.

Host range: The primary host of significant economic importance is Arabica coffee (Coffea arabica). However, it is a polyphagous parasite that can infect various other crops, including fruit trees and certain vegetables. Many weed species can act as alternative hosts, which complicates the eradication process in infected fields.

Biology and life cycle: The life cycle comprises an egg stage, four larval stages, and an adult stage. Infective second-stage juveniles migrate through the soil to locate a root, penetrate the root tip, and establish feeding sites. Inside the root tissue, the nematodes undergo metamorphosis, with females becoming sedentary and producing eggs within a gelatinous matrix.

Damage and pathogenicity: Infestation results in the formation of large galls on the root system, which disrupts the vascular tissues of the plant. This internal damage limits the uptake of water and nutrients, leading to visible symptoms such as yellowing of leaves, stunted development, and general decline of the plant, often resulting in premature death.

Control measures: Managing Meloidogyne paranaensis requires integrated pest management practices. Key strategies include:

• Utilization of nematode-free certified seedlings.
• Selection of resistant or tolerant cultivars.
• Strict quarantine measures to prevent the spread of contaminated soil.
• Implementing crop rotation with non-host cover crops to reduce soil inoculum levels.
• Chemical treatments or bio-nematicides for nursery sanitation.