Free Plant Protection MCQs with Answers

• A. Aplud
• B. White fly
• C. Jassid
• D. Heliothus

Explanation: The whitefly, especially Bemisia tabaci, transmits cotton leaf curl virus (CLCuV) while feeding on infected and healthy plants.

• A. Bacillus thuringensis
• B. Bemisia tabaci
• C. Bemisia trachyplerus

Explanation: In Bt cotton, Bt refers to Bacillus thuringiensis, a bacterium whose insecticidal proteins provide protection against important…

• A. American boll worm
• B. Aphids
• C. Spotted boll worm
• D. CLCV

Explanation: The major fall in Pakistan’s cotton production in 1992–93 was associated with cotton leaf curl virus, abbreviated CLCV.

• A. Fungi
• B. Bacteria
• C. Virus
• D. None of the above

Explanation: Fungi lack chlorophyll and therefore cannot manufacture food by photosynthesis; they obtain nutrients from organic matter or living hosts.

• A. Amino acid
• B. Valine
• C. Auxins
• D. Cytokmins

Explanation: 2,4-D is a synthetic auxin, or auxin-like herbicide, that causes uncontrolled growth in susceptible broadleaf weeds.

• A. 10-20%
• B. 5-15%
• C. 20-50%
• D. 20-60%

Explanation: Weed competition in rice can cause substantial yield loss, commonly reported within the broad range of about 20 to 60%, depending on weed…

• A. Saprophytes
• B. Parasites
• C. Obligatory parasites
• D. Bacteria

Explanation: Saprophytes obtain nutrients from dead and decaying organic matter rather than producing their own food.

• A. Pest and insect management
• B. Weed and pest management
• C. Disease and pest management
• D. non of these

Explanation: Allelochemicals released by plants can suppress the germination or growth of weeds and may also affect certain pests, making them useful…

• A. Soil management
• B. non of these
• C. Water management
• D. Weed management

Explanation: Allelopathy is especially useful in integrated weed management because crop residues or root exudates can naturally inhibit weed…

• A. Both a and b
• B. weed seed
• C. Crop seeds
• D. non of these

Explanation: Annual ryegrass can release root-associated allelochemicals that inhibit the germination and early growth of both crop and weed seeds.

• A. Seed deterioration
• B. seed germination
• C. Seed swelling
• D. non of these

Explanation: A common effect of allelochemicals is inhibition of seed germination, often followed by reduced seedling growth.

• A. Bacterial disease
• B. Fungal disease
• C. Viral disease

Explanation: Cotton root rot is caused by the soil-borne fungus Phymatotrichopsis omnivora, so it is a fungal disease.

• A. Allelopathy
• B. Allergy
• C. Parasitism
• D. Antagorusm

Explanation: Allelopathy is the chemical inhibition or stimulation of one plant by substances released by another living plant.

• A. Virus
• B. Bacteria
• C. Fungi
• D. non of these

Explanation: Bt cotton contains a gene from the soil bacterium Bacillus thuringiensis, which produces Cry proteins toxic to certain bollworm larvae.

• A. Cotton leaf cover virus
• B. cotton leaf cotton virus
• C. cotton leaf curl virus
• D. cotton leaf complete virus

Explanation: CLCV expands to cotton leaf curl virus, a major virus disease of cotton transmitted mainly by the whitefly Bemisia tabaci.

• A. Defoliant
• B. Aerosol
• C. Persistence
• D. Desiccant

Explanation: Persistence is the ability of a pesticide to remain active on or in the treated material for a period, usually because it has low…

• A. LD75
• B. LD50
• C. None of the Above
• D. LC50

Explanation: LC50 means the lethal concentration that kills 50% of an exposed population.

• A. Poison
• B. Poisonous material
• C. None of the Above
• D. Both of them

Explanation: A toxicant is a poisonous material or substance capable of producing harmful effects in an organism.

• A. Adjuvant
• B. Adhesive
• C. Carrier
• D. Agitation

Explanation: A carrier is the inert material used to dilute and distribute a pesticide’s active ingredient, such as water, dust or an oil-based…

• A. Bait
• B. Acute poisoning
• C. Chronic poisoning
• D. Defoliant

Explanation: A defoliant causes leaves to drop from a plant, either by accelerating leaf abscission or damaging foliage.