Foliar Nematode Information from UC Davis
UC Davis has 10 Ph.D Nematoligist on staff. Lots of interesting
information. Check it out if you can't get to sleep tonight. This is copied from
their homepage. Here's a link to their homepage.
Taxonomy, Common Name, Disease
- CLASS: SECERNENTEA
- SUBCLASS: DIPLOGASTERIA
- ORDER: TYLENCHIDA
- SUBORDER: APHELENCHINA
- FAMILY: APHELENCHOIDIDAE
- SUBFAMILY: APHELENCHOIDINAE
Scientific name - Aphelenchoides
Common name - foliar nematode
Hosts Wide host range. Over 250 hosts in 47 families, including fern,
lily, begonia, African violet, strawberry, and many aquatic plants.
Distribution Temperate and tropical regions.
Life Cycle Migratory endoparasite in leaves, but also feeds
ectoparasitically on leaf and flower buds in strawberry, for example. Nematode
enters leaves through stomata or directly. Sexually reproducing; males required.
Life cycle completed in 10-13 days; female produces about 30 eggs. Does best in
moist, cool situations.
Symptoms-Pathogenicity Nematode feeding causes blotches and necrotic
lesions between veins on leaves which start as water-soaked spots and then turn
brown. In strawberries, nematode causes malformed leaves with crinkled edges.
Management Roguing plants with symptoms. Hot water treatments. Foliar
or soil treatments with systemic chemicals.
Characteristics Aphelenchoides - Females elongate, slender,
usually under 1 mm long; lip region flattened to rounded, slightly offset from
body. Head skeleton weak, stylet usually less than 20 um long with only small
basal thickenings or knobs. Esophagus with well developed median bulb almost
filling body width; esophageal glands in a long lobe overlapping intestine
dorsolaterally. Vulva posterior (V = 65-75%) with single anterior gonad and
usually a post-vulval sac. Tail conical, often about three to five times the
anal body width, sometimes ending in minute terminal spike(s). Male
esophageal region similar to female; tail end with paired rose-thorn shaped
spicules, no gubernaculum or bursa but with three pairs of subventral
papillae. When killed by heat the male tail curls ventrally into a 'walking
- Evans, K., D.L. Trudgill, and J.M. Webster. 1993. Chapter 1. Extraction,
Identification and Control of Plant Parasitic Nematodes. in Plant Parasitic
Nematodes in Temperate Agriculture. CAB International, UK. 648 pages.
- Siddiqi, M.R. 1975. Aphelenchoides fragariae. C.I.H. Descriptions
of Plant-parasitic Nematodes. Set 5, No. 74. Commonwealth Institute of
Parasitology. C.A.B. International. 4 pages.
- Jenkins, W.R. and D.P. Taylor. 1967. Chapter 16. Foliar or Leaf Nematodes:
Aphelenchoides and the Coconut Nematode: Rhadinaphelenchus. in
Plant Nematology. Reinhold Publishing Corporation, New York. 270 pages. (page
- McKenry, M.V. and P.A. Roberts. 1985. Phytonematology Study Guide.
University of California Division of Agriculture and Natural Resources
Publication 4045. 56 pages. (page 7).
- Agrios, G.N. 1969. Plant Pathology. Academic Press, New York. 629 pages.