MELOIDOGYNE ACRONEA

IDENTITY: Scientific name: Meloidogyne acronea
Coetzee, 1956
 Common name: African cotton root-knot nematode

NOTES ON TAXONOMY AND BIOLOGY: Female M. acronea have a circular cuticular perineal pattern with faint, smooth and intermittent striae. This root-knot nematode has sedentary endoparasitic habits. Second-stage juveniles (J2) in the soil penetrate host roots where they establish a specialized feeding site (giant cells) in the stele. As J2 develop they cause slight root swellings and become swollen females, which retain the eggs and produce also egg masses. Females rupture root cortex and protrude with the egg masses from the root surface. J2 emerge from either the egg masses or the decayed female body at the end of the female reproductive cycle.

GEOGRAPHICAL DISTRIBUTION: Malawi and South Africa.

HOSTS: Cotton (Gossipium hirsutum) is the primary host. Other hosts include pigeon pea (Cajanus cajan), sorghum (Sorghum bicolor) and tomato (Lycopersicon esculentum). Poor hosts are beans (Phaseolus sp.), clusterbean (Cyamopsis tetragonoloba), Jamaica sorrel (Hibiscus sabdariffa),  kidney bean (Phaseolus vulgaris), koracan (Eleusina coracana), lovegrass (Eragrostis sp.), pearl millet (Pennisetum glaucum), peanut (Arachis hypogea), potato (Solanum tuberosum), purging croton (Croton tiglium), sennas (Cassia sp.) and sunflower (Helianthus annuus).

CROP LOSSES: Yield suppression by 90% is reported on cotton (Page, 1983) and by 56% on sorghum.

MEANS OF MOVEMENT AND DISPERSAL: Through root material, soil debris, and poorly sanitized bare root propagative plant material.

RATING: (L) Although this nematode should be excluded if it is detected, it was given a low priority rating for a complete risk assessment because of its limited distribution and pathways for entry.

REFERENCES:
    CAB International. 2001. Meloidogyne acronea in Crop protection compendium, global module, 3rd editon. Wallingford, UK: CAB International.
    Page, S. L. J. 1983. Biological studies of the cotton root nematode Meloidogyne acronea. Ph.D. Thesis, London University, London.
    Page, S. L. J. 1985. Meloidogyne acronea, CIH description of plant parasitic nematodes. Set 8, No. 114. St. Albans, UK: Commonwealth Institute of Helminthology.