Agriculture Exams (Agri Croppro) – Page 12

#220. In some genera of plant parasitic nematodes like Meloidogyne, Globodera, Heterodera, etc., males and females have entirely different morphology. How is this phenomenon called?
A sexual degeneration
B sexual mutation
C sexual diversity
D sexual dimorphism
Answer: sexual dimorphism
#221. If juveniles and adults are motile and outside of roots during all life cycle stages a plant parasitic nematode is a/an
A migratory ectoparasite
B direct parasite
C indirect parasite
D migratory endoparasite
Answer: migratory ectoparasite
#222. If juveniles and adults are motile during all life cycle stages but may be either within or inside of roots a plant parasitic nematode is a/an
A migratory ectoparasite
B migratory endoparasite
C direct parasite
D indirect parasite
Answer: migratory endoparasite
#223. If an infective stage juvenile enters a root, takes up a feeding site and remains at that site a plant parasitic nematode is a/an
A direct parasite
B sedentary endoparasite
C sedentary ectoparasite
D indirect parasite
Answer: sedentary endoparasite
#224. Education, quarantine, using certified planting materials, checking suspect materials before planting, and cleaning equipment, are examples of what type of management of plant parasitic nematodes
A prevention
B protection
C eradication
D immunization
Answer: prevention
#225. Crop rotation, using resistant varieties, fallowing, using cover crops, and varying the date of planting and harvest are examples of what type of management of plant parasitic nematodes
A biological
B cultural
C physical
D chemical
Answer: cultural
#226. The most widely used category of chemicals for management of plant parasitic nematodes has traditionally been
A mebendazoles
B carbamates
C fumigants
D natural products
Answer: fumigants
#227. A broad-spectrum gaseous chemical used for management of plant parasitic nematodes that is thought to be damaging to the ozone layer is
A metam-sodium
B carbamate
C methyl bromide
D all of the above
Answer: methyl bromide
#228. The practice of incorporating fresh plants or plant materíals onto the soil as a mean to control plant parasitic nematodes is called
A biological control
B biofumigation
C fallowing
D organic fertilization
Answer: biofumigation
#229. What is the main compound present in some species of Tagetes that repels and/ or suppress certain plant parasitic nematodes?
A alpha tertienyl
B beta-ocimene
C isothiocyanate
D all of the above
Answer: alpha tertienyl
#230. What is the practice of leaving the farm unplanted for certain period, thus, depriving the nematodes of their hosts which brings their population into a significantly low level?
A crop rotation
B sanitation
C solarization
D fallowing
Answer: fallowing
#231. The following except for one are responsible for nematode control by incorporating fresh chicken dung into infested soils.
A It harbors lots of microorganisms that may be parasitic to nematodes
B It generates heat during decomposition
C It increases soil fertility
D It imparts toxic compounds
Answer: It increases soil fertility
#232. In the Philippines, BIOACT and BIOCON are commercial products of a fungus that parasitizes Maloidogyne spp., Radopholus similis, Rotylenchulus reniformis, etc. What is that fungus?
A Paecilomyces lilacinus
B Verticillium chlamydosporium
C Arthrobotrys oligospora
D Rhizoctonia solani
Answer: Paecilomyces lilacinus
#233. What is the common pattern of nematode spatial distribution in a field?
A Uniform
B Random
C patchy
D none of the above
Answer: patchy
#234. Which of the following facilitates long-distance spread of nematodes?
A water
B drainage
C infected seeds/ bulbs/ corms
D soil particles adhering on farm equipment
Answer: infected seeds/ bulbs/ corms
#235. In what order does the most of the important genera of plant parasitic nematodes belong?
A Triplonchida
B Dorylaimida
C Tylenchida
D Aphelenchida
Answer: Tylenchida
#236. What is the most preferred site for root penetration of infective stage of Meloidogyne spp.?
A root cap
B zone of elongation
C zone of differentiation
D zone of maturation
Answer: zone of elongation
#237. What soil texture is generally most preferred by plant parasitic nematodes?
A silty
B muddy
C sandy
D clayey
Answer: sandy
#238. Which life stage of the nematode will NOT be killed by a systemic nematicide?
A eggs
B juveniles
C females feeding inside the roots
D Females feeding on the root surface
Answer: eggs
#239. Hot water treatment is a very practical method of controlling nematodes that are possibly harbored by planting materials, thus preventing their introduction to a new locality. The following planting materials can be subjected to this procedure EXCEPT for
A seed potato
B rice seeds
C onion bulb
D banana corm
Answer: seed potato