Nematropica (2000) 30, 55-61

M. Di Vito, R. Crozzoli and N. Vovlas (2000)
Pathogenicity of Meloidogyne exigua on coffee (Coffea arabica L.) in pots
Nematropica 30 (1), 55-61
Abstract: The relationship between a geometric series of fourteen initial population densities (Pi) of Meloidogyne exigua between 0 and 512 eggs and juveniles/cm³ soil and growth of coffee (Coffea arabica) was investigated in one-liter clay pots. The Seinhorst model, y = m + (1 - m) z^P-T, was fitted to average plant height, internode length, and fresh top weight. Tolerance limits (T) to the nematode for height, weight and lengths of internodes of coffee plants were 5.9, 1.2 and 6.2 eggs and juveniles/cm³ soil, respectively. The minimum relative yields (m) were 0.7 and 0.4 at Pi > 256 eggs and juveniles/cm³ soil for height and internode length of plants, respectively, and 0.5 at Pi > 128 eggs and juveniles/cm³ soil for plant top weight. Maximum nematode reproduction was 422-fold at lowest initial population densities (Pi). The histopatology of coffee roots infected by M. exigua reveals swollen root tips and axes. Nematode egg masses were visible on root surfaces only in small root-galls whereas commonly they were embedded in the root tissues. Multiple infection sites were common, resulting in galls containing several females. Formation of specialized cells (giant cells) in the stele, disruption of the vascular system, and hyperplasia of the vascular parenchyma was the most common anatomical alterations observed in infected coffee roots.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Renato Crozzoli, Nicola Vovlas

Research topic(s) for pests/diseases/weeds:
damage/losses/economics

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Meloidogyne exigua	Coffee (Coffea)