Morphological characteristics of Scutellonema bizanae from China

Abstract

Van den Berg et Heyns (1973) described two species of Scutellonema Andrassy (S. bizanae and S. multistriatum) and differentiated these species by spicule length (29.8- 31.3 [Lm and 22.1-27.6 [Lm respectively) and body annulus width (1.8 vs 1.1 [Lm). Germani et al. (1985) in a revision of the genus Scutellonema examined type material (2 Q and 1 Cf of S. bizanae) (3 Q and 2 Cf of S. multistriatum) and in view of only minor differences between the two populations they consider them synonyms. In November 1984 a bisexual species of Scutellonema Andrassy, 1958 was extracted from soil samples collected in grape (Vitis vinifera 1.) and apple (Malus communis 1.) orchards in the Henan province of China. Study of 45 females and 5 males confirmed that the species is con specific with Scutellonema bizanae Van den Berg et Heyns, 1973. The presence of S. bizanae in China in the rhizosphere of cultivated plants extends the host and distribution record for this species which was previously known to occur only in South Africa from where it was originally described. This article extends the known range of variahility of the principal descriptive characters while the most important diagnostic external features, longitudinal striations on the basal lip annulus and areolation of the lateral field at the level of the scutella, are illustrated hy scanning electron microscopy (SEM) observations.