Animalia ( 동물계 )

Metazoa ( 후생동물아계 )

Bilateralia

Protostomia ( 선구동물군 )

Pseudocoelomata

Aschelminth ( 대형동물문 )

Nematoda ( 선충강 )

Definition of nematode

1. Tripoblastic2. Bilaterally symmetrical3. Pseudocoel4. No respiratory, circulatory system5. Non-segmented

Nematode body shape

1. Filiform ( 선형 )2. Fusiform ( 방추형 )3. Pyriform(pear shape or lemon shape)4. Sexual dimorphism

Color-transparent (yellow or brown)

Size of nematode

1. Plant parasitic nematode : 0.2 ~ 10 X 0.5 ~1.5 mm

2. Animal parasitic nematode - Ascaris, 40 cm - Giant kidney worm,1 m x 1,5 cm - Placentonematode gigantismo spem whale, 8.5m x 2.5 cm

Pratylenchus spp. Cyst nematode

J2, root-knotnematode attacking plant root tip

J2, hatching from egg

A: Fusiform B,C: Filiform

D, E: Partly filiformF: Pyriform

J1

J2

J3

J4

Male

Female

History of nematology

1. Ching, 2700 B.C. -Chinese physician, Ascaris lumbricoides 2. German Egyptologist, 1553-1550 B.C. - “Ebers’ Papyrus” (1872) - Ascaris, Guinea worm 3. Bible, 1250 B.C. - Guinea worm 4. Plurtarch, 181-146 B.C. - Guinea worm, Dracunculus medinensis (Dracunculus = “little snake from Medina”)

Europe

1. Needham, 1743 :First plant parasitic nematode Anguina tritici (seed-gall nematode)2. Berkeley, 1855 :Root-knot nematode on cucumber3. Kuhn, 1857 :Ditylenchus dipsaci (stem and bulb nematode)4. Schacht, 1859 :Heterodera schactii (sugarbeet nematode) 5. Kuhn, 1871 :Fist soil fumigant, “cardon disulfate”

America

1. Neal & Atinson, 1889 :Independently published root-knot nematode2. Atkinson, 1892 :Root-knot nematode and Fusarium on cotton3. N. A. Cobb, 1907 :USDA, developed the subject of nematodes Father of American nematologist 4. Publication Journal of Nematology, 1969

Nematode- important role in modern biology

1. Butschli,1873-1875 : first observed polar bodies during nuclear division in nematode2. Van Beneden,1883 : description of chromosomes of Ascaris suum 3. Boveri,1899 : fate of the cells during embryogenesis 4. W. B. Wood, 1988 : selected C. elegans as a promising model animal for a genetic, ultrastructural, and behavioural investigation of development and function in a simple nervous system