Introduction to Biocontrol Agents

Q.

Which one of the following is an example of carrying out biological control of pests/diseases using microbes?

1. Bt-cotton to increase cotton yield

2. Lady bird beetle against aphids in mustard

3. Nucleopolyhedrovirus against white rust in Brassica

4. Trichoderma sp. against certain plant pathogens

Q.

Select the correct group of biocontrol agents.

1. Nostoc, Azospirillum, Nucleopolyhedrovirus

2. Bacillus thuringiensis, Tobacco mosaic virus, Aphids

3. Trichoderma, Baculovirus, Bacillus thuringiensis

4. Oscillatoria, Rhizobium, Trichoderma

Q.

To which genus do most of the baculoviruses used as biological control agents belong?

Q.

How do microorganisms affect plant growth?

Q. A common biocontrol agent for the control of plant diseases is

1. Baculovirus
2. Bacillus thuringiensis
3. Glomus
4. Trichoderma

Q. Nucleopolyhedrovirus is used as a biocontrol agent.

1. True
2. False

Q.

All blue green algae have the ability to fix nitrogen.

1. True
2. False

Q. Which one of the following helps in the absorption of phosphorus from soil by plants?

1. Glomus
2. Rhizobium
3. Oscillatoria
4. Azotobacter

Q. One of the major difficulties in the biological control of insect pests is

1. Practical difficulty of introducing the predator to specific areas.
2. Method is less effective as compared with the use of insecticides
3. Predator does not always survive when transferred to a new environment
4. The predator develops a preference to other diets and may itself become a pest.

Q.

Is Trichoderma a biopesticide?

Q. Which of the following statements are true?
(i) Trichoderma is a fungi that is pathogenic to crop plants
(ii) Baculoviruses are parasites of arthropods
(iii) Baculoviruses do not harm non-target insects

1. (i) and (ii)
2. (i) and (iii)
3. (ii) and (iii)
4. (i), (ii) and (iii)

Q.

Is dragonfly a biocontrol agent?

Q.

The control of a pest by the introduction of a natural enemy or predator is called

1. artificial control

2. confusion technique

3. biological control

4. genetic engineering.

Q.

A common biocontrol agent for the control of plant diseases is?

1. Trichoderma.

2. Glomus

3. Bacillus thuringiensis

4. Baculovirus

Q.

What are Cyanobionts?

Q. Assertion :Organic farming is very beneficial for farmers to increase crop production. Reason: Bacteria, fungi, mycorrhiza, cyanobacteria are better biofertilizer which fixes nitrogen and increase soil fertility.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Is Trichoderma edible?

Q. Select the odd one out with respect to Green revolution measures

1. Use of high yielding varieties
2. Use of agricultural machinery
3. Use of cow dung as fertilizer
4. Use of pump for irrigation

Q. State whether the following statements are true (T) or false (F):
I - Chemical pesticides pollute the environment.
II - Biopesticides aim at eradicating the pest population.
III - Eradication of pest population affects the stability of the ecosystem.

1. I - T, II - F, III - F
2. I - T, II - F, III - T
3. I - T, II - T, III - F
4. I - F, II - F, III - F

Q. Nucleopolyhedrovirus is used as a biocontrol agent.

1. True
2. False

Q. Some other examples of biocontrol agents other than Bacillus thuringiensis is/are?

1. Trichoderma
2. Mycorrhiza
3. Rhizobium
4. Baculovirus

Q.

Which one of the following helps in absorption of phosphorus from soil by plants?

1. Anabaena

2. Glomus

3. Rhizobium

4. Frankia

Q.

In confusion technique, the pheromone coated paper strips are thrown over an area in order to:

1. Repel insects from an area

2. Confuse males so that they are unable to locate the females

3. Confuse females so that they are unable to locate the males

4. Attract insects and kill them

Q. Which of the following are biopesticides?

1. DDT
2. Both of the above
3. None of the above
4. Azadirachtin

Q. A common biocontrol agent for the control of plant diseases is:

1. Baculovirus
2. Bacillus thuringiensis
3. Glomus
4. Trichoderma

Q. Coralloid root help Cycas in?

Q.

Select the mismatch association among the following:

1. Frankia – Alnus

2. Rhodospirillum – Mycorrhiza

3. Anabaena – Nitrogen fixer

4. Rhizobium – Alfalfa

Q. State whether the following statements are true or false:

Metamorphosis in insects (like silk moth) is brought about by thyroxine hormone.

1. True
2. False

Q. The use of biological methods for controlling plant diseases and pests is known as .

1. insecticide
2. pesticide
3. herbicide
4. biocontrol

Q.

Which one of the following helps in absorption of phosphorus from soil by plants?

1. Anabaena

2. Glomus

3. Rhizobium

4. Frankia