NEMATOLOGY 100 FINAL EXAM December 13, 1997 2 hours (50% of overall grade) 1. (15 points) For each of the listed behavioral characteristics exhibited by all or some types of plant- parasitic nematodes indicate, being as specific as possible: a) the nature of the external stimulus b) the source of the external stimulus c) the nematode genera that exhibit the response d) any known artificial stimulants that might be used to disrupt the behavior (i) General movement towards roots a) b) c) d) (ii) Selection of specific points of entry on roots a) b) c) d) (iii) Stimulated egg hatch a) b) c) d) (iv) Aggregation of males around females a) b) c) d) (v) Location of stomata on leaf surfaces a) b) c) d) 2. (15 points) Briefly describe the modes of parasitism of the fungi that are antagonistic to nematodes. Provide examples where possible. 3. (10 points) Discuss the methods by which nematodes survive resource-limited and adverse environmental conditions. Give specific examples. 4. (10 points) Describe the events, stimuli and responses from the time that juveniles of Meloidogyne spp. penetrate the root epidermis until a functional giant cell feeding site is established. 5. (15 points) For the nematodes listed below, briefly indicate: a) economic importance in California and worldwide b) host range and types of plants affected c) infection site/mode of parasitism (i) Bursaphelenchus xylophilus - the pine wood nematode a) b) c) (ii) Rotylenchulus reniformis - the reniform nematode a) b) c) (iii) Xiphinema index - a dagger nematode a) b) c) 6. (15 points) What nematode-management strategies would you recommend for establishment of a banana plantation in Panama? Provide recommendations for actions to be taken before planting and for continued management after planting. 7. (10 points) What is the principle, and what are the constraints, of using trap crops to manage plant-parasitic nematodes. Indicate the types of nematodes and crop production systems for which you might consider the trap crop approach. 8. (10 points) Indicate which of the following nematicides are: a) halogenated hydrocarbons b) fumigants c) nonfumigants d) organophosphates e) carbamates (note there may be more than one answer in each case) (i) Telone (ii) Temik 10G (iii) Vapam (iv) Furadan (v) Methyl bromide Name: Page: 9