identification of cyst nematode (Heterodera and Globodera)

1. Heterodera
Cyst Nematode
Presented by
R MOHANAPRIYA
M.Sc. Agri (Plant Pathology)
JSA College of Agriculture and Technology

2. Systematic position
Phylum : Nematoda
Class : Secernentea
Order : Tylenchida
Suborder : Tylenchina
Super family : Tylenchoidea
Family : Heteroderidae
Sub-family : Heteroderinae
Genus : Heterodera
Species : Sugarbeet cyst nematode – H. schachtii
Cereal cyst nematode - H. avenae
Rice cyst nematode - H. oryzicola
Pigeonpea cyst nematode - H. cajani
Soyabean cyst nematode- H. Glycines
Maize/Corn cyst nematode – H. Zeae
Clover cyst nematode – H. Trifolii
Brassica cyst nematode – H. cruciferae
Major hosts : Species are host specific
Type of parasitism : Sedentary endoparasite

3. History
• In the early 1800s, "beet fatigue" was used to describe the decreased sugar
beet yields which occurred after repeated planting on the same field.
• At first, this decrease was believed to be the result of nutrient depletion, but
in 1859 the botanist H. Schacht discovered nematode cysts on the roots of
affected plants.
• The sugarbeet cyst nematode (Heterodera schachtii )was first discovered by
schacht in 1859 from Germany as the causal organism of “rubenmudigkiet” or
“beet tiredness”.
• Later named as Heterodera schachtii by Schmidt in 1871.

4.  Economically important nematode in india
 Gr. heteros- different , deros- skin, body wall
 Host specific
 hard brown cyst wall as compared to soft transparent body wall of other
nematodes (female turns into a hard brown cyst enclosing eggs inside)

5. Host range
 It can infect more than 200 plant species, including sugarbeet, raddish,
broccoli,cabbage.
 It can also survive on weeds.
Distribution
• Widely distributed in all sugar beet growing areas of the world.
• Today, SBCN is present in forty different countries and seventeen states in the
United States, including Washington, Oregon, Utah, and Idaho.

6. Spread
 SBCN is a soilborne pest, so anything that can move soil will move the nematode.
 Cysts can be spread by machinery, animals, water and tare soil from harvested
beets.
 In the soil profile, cysts can be found from the surface to 24 inches deep, but the
highest numbers are found in the root zone (2 to 10 inches soil depth).

7. Mature female and cyst
- Lemon shaped with a short neck and terminal cone(vulvalcone) turning
into a hard wall cyst brown or black in colour(0.5 to 0.8mm)
- Vulva terminal
- Anus dorsally subterminal
- Vulval fenestration present (ambifenestrate/bifenestrate)
- Eggs in the body some times in gelatinus matrix
- Bullae often present

10. Male
- Vermiform
- 1mm to 2mm length
- Stylet - short in males with rounded basal knobs, more than 0.02mm long
in juveniles.
-Oesophagus: with well developed median bulb and lobe extending back
and overlapping the intestine on all sides
-Spicules near the posterior end (robust), gubernaculum present, bursa
absent, tail end twisted

12. Second juvenile stage
- Slender, juveniles 0.3 to 0.6mm length
- 400-500µm long
- Cephalic sclerotization
- Stylet more robust
- Oesophagus overlap intestine ventally
- Tail hyaline

13. Life Cycle and Survival
-Sedentary endoparasite,
-The nematode survives in the soil as cysts that contain eggs and juveniles.
 Under favorable conditions — warm temperatures (70 to 81 degrees F) and
sufficient soil moisture — and the presence of root exudate from hosts,
second-stage-juveniles hatch from eggs, enter the root tissue, and move to
cortical tissues where they feed.
 Several generation in one season

16. Symptoms
 Fields may be uniformly infested or may have localized areas of infestations.
 Circular to oval spots where poor plant stands and growth are observed. The
pathogen can attack plants of any age, and seedlings or young beets may be
killed, resulting in reduced stands.
 Young plants infected by the disease have elongated petioles and remain
stunted until harvest.
 Leaves of severely affected plant additionally wilt and have pronounced
yellowing.

20. Management
Sanitation: Tare soil should not be dumped back into fields.
Plant SBCN tolerant cultivars which are available, but be aware of their
susceptibility to other diseases, including Cercospora and Rhizoctonia root
rot.
Rotation with non-host crops, including wheat, barley, corn, bean, potato
and alfalfa.
Three- to four-year rotation is needed in heavily infested fields; rotations
with non-host may reduce initial SBCN population by 40-60 percent in a
year.

21. Plant trap crops which attract SBCN, but do not allow them to develop and reproduce.
Some SBCN-tolerant cultivars of oil seed radish (Defender, Image and Colonel) and
mustard are effective
Early planting when soil temperatures are not favorable (< 59 degrees F) for infection
by SBCN.
Control weeds that are hosts for SBCN in sugar beet and rotation crops.
Avoid returning tare soil with SBCN to fields in which sugar beet is grown.
Some nematicides may be effective, but are typically difficult to apply and may be
uneconomical.
Biological seed treatment which utilize spores of Pasteuria nishizawae may help to
manage SBCN on tolerant sugarbeet varieties.

22. Globodera
Potato Cyst Nematode
1st reported by Jones 1961 in Nilgiri
hills

23. Systematic position
Same as Heterodera
Common Name
Golden nematode, golden potato cyst
nematode, yellow potato cyst nematode,
golden eelworm
Potato – cool climate
Hills –summer
Plains –winter
Sedentory endo parasite
Morphology
Similar to Heterodera but the cyst is
globose, vulva and anus are not on a
terminal cone, vulval slit is surrounded
by a single, circular fenestra

24. Only one generation in a season and
requires potato root exudates for
hatching eggs

26. Root knot nematode
Meloidogyne

27. Systematic position
Phylum : Nematoda
Class : Secernentea
Order : Tylenchida
Suborder : Tylenchina
Super family : Tylenchoidea
Family : Heteroderidae
Sub-family : Meloidogyninae
Genus : Meloidogyne
Species : M. incognita, M. javanica, M. arenaria, M. hapla M.
graminicola,
Major hosts : Vegetables, papaya, potato, betelvine,
groundnut, carrot ad rice

28. Body: elongated in juveniles (0.5mm in length) and males (1.0-2.0mm in length),
typically saccate, spheroid, with a distinct neck in females (0.8 mm long and 0.5mm
wide), head skeleton weak.
Stylet: strong with rounded knobs in males, more slender in females than in males
and juveniles but with strong basal knobs.
Oesophagus: with very large median bulb followed by a short isthmus.

30. Female: vulva and anus typically opposite to neck and surrounded by a pattern of fine
lines resembling human finger prints called ”perineal pattern‟; ovaries didelphic,
convoluted.
Male: tail - short, hemispherical; spicules - robust, very near to the tail terminus, bursa
absent.

31. Biology:
Meloidogyne spp. are sedentary endoparasites. Second stage juveniles are infective and
establish a feeding site (syncytium) involving vascular tissues, endodermis and pericycle
cells. The feeding site comprises of 8-12 multinucleate „giant cells‟. The second stage
juveniles start swelling and develop to third and fourth stages. After final moult, males
acquire vermiform shape and come out into the soil. Females attain saccate shape and lay
eggs in a gelatinous matrix (egg mass) on the root surface. Reproduction is generally by
parthenogenesis and nematode completes 7- 8 generations in a year.

33. Management
• Cover crops
• crop rotation
• flooding and solarization of fields
• Fumigants (such as 1,3-dichloropropene, methyl bromide and dazomet) are commonly
applied as pre-plant treatments
• broad-spectrum fumigants, nervous system toxins (including oxamyl and fenamiphos)