Fig 8. Nematode (Litylenchus crenatae subsp. mccannii) assessment of leaves and beech (Fagus grandifolia) buds in early spring.
(A) Representative branch showing sets of asymptomatic and symptomatic beech leaf disease (BLD) leaves, and poorly developing buds. (B-C) Detection of nematodes in symptomatic BLD leaves using acid fuchsin staining (B). Nematodes (arrows) were found migrating on the abaxial side of the leaf and penetrating the leaf tissues (C-C’). (D) Representative symptomatic BLD leaves dissected from poorly developing buds. (E) Percentage of asymptomatic and symptomatic BLD leaves associated with 50 poor-developing buds rated according to the phenotype scale presented in Fig 1. (F) Active nematodes and eggs extracted from a single, poorly developing bud. (G) Numbers of nematodes extracted from 50 poorly developing buds. Buds were classified from 0 to 4 based on their bud scale phenotype (see Fig 1). Scale bars: 5 mm (B); 1 mm (C, D, F); 500 μm (C´).
