Characterization of a Venezuelan population of Aphelenchoides ritzemabosi on chrysanthemum

Abstract

Chrysanthemum (Dendranthema grandiflorum) from San Pedro de Los Altos, Miranda State, was found infected with the foliar nematode Aphelenchoides ritzemabosi. Chrysanthemum leaves were distorted, smaller and discoloured with blackish brown spots. These irregular necrotic areas occupied 10 to 100 % of the leaf surface. All life stages of the nematode were extracted from infected leaves incubated in distilled water. The female body was slender, lateral field with four longitudinal incisures, excretory pore posterior to nerve ring, genital tract monoprodelphic, uterine sac present and containing sperm, tail conoid with two to four terminal minute processes. The number of males was approximately 20% of the population. Males with posterior end of body curved and a tail peg with 2-3 processes. Measurements of females, males and juveniles of the nematode are reported. This is the first report of A. ritzemabosi infecting chrysanthemum in Venezuela.