NEMATOLOGY 100 - FINAL EXAM Name:
December 14, 1994 2 hours
(50% of overall grade)
1. (10 points)
What features would you design into a nematode species to enhance its
success in an annual cropping system?
Discuss these characteristics in relation to the sugarbeet cyst nematode
and the dagger nematode.
2. (12 points)
On December 8, 1994 the California Department of Pesticide Regulation
announced that permits will be issued in 13 counties for the use of
Telone II nematicide.
a) What type of nematicide is Telone and how does it move through soil?
b) If you were asked to designate three California crops that you
considered to have highest priority for use of this nematicide,
what would they be, and why?
c) What are the target nematode species in the case of each of your
designated crops?
d) Discuss the pros and cons of using the nematicide in situations
where it has not been used since 1990.
3. (10 points)
Discuss resistance to desiccation as a nematode survival mechanism.
Use examples of genera, species, life stages, and feeding habits
where it may be important. Consider the agricultural significance
in each case.
4. (10 points)
Match the following. (Some letters may be used several times, others
may not be used at all. There may be several answers to each question).
_________1. Animal or human parasite a)Caenorhabditis elegans
_________2. Can feed on fungi b) Longidorus africanus
_________3. Predaceous nematode c) Ditylenchus destructor
_________4. Bacterial-feeding nematode d) Heterorhabditis bacteriophora
_________5. Host-mediated egg hatch e) Mononchus sp
_________6. Sedentary endoparasite f) Sheath nematode
_________7. Virus transmission g) Rotylenchulus reniformis
_________8. A-rated pest (California) h) Wucheria bancrofti
_________9. Migratory endoparasite i) Soybean cyst nematode
________10. Order Tylenchida j) Meloidogyne hapla
5. (10 points)
Describe relationships between seed-gall nematodes and bacteria of the
genus Clavibacter
6. (10 points)
Describe current understanding of the glandular activity and glandular
secretions of root-knot nematodes with regard to stimulating and
maintaining giant cells.
7. (10 points)
Radopholus similis is an important parasites of bananas in Central
America. What type of damage will they cause? How are the nematodes and
their damage managed?
8. (8 points)
What factors will you consider in developing crop rotation sequences for plant-
parasitic nematodes in the genus Meloidogyne and the genus Heterodera.
9. (10 points)
Describe the proposed causality of bacterial canker of peach in California.
10. (10 points)
Briefly describe the modes of capture/infection of nematodes by their
fungal parasites. Provide an example of a fungus genus in each case.