Pest and Weed Management Flashcards

Which group of insects are important biological control agents for aphids in crops?

Answer: Ladybugs (lady beetles) and parasitic wasps

Lady beetles and parasitic wasps are natural enemies of aphids, feeding on or parasitizing them and reducing aphid population growth.

What is herbicide resistance in weeds?

Answer: Inherited ability of a weed biotype to survive a herbicide dose that kills normal plants

Herbicide resistance is a heritable trait in weed populations that allows surviving plants to tolerate doses that would kill susceptible biotypes of the same species.

Soybean cyst nematode (SCN) is best managed long-term using what strategy?

Answer: Rotating SCN-susceptible and resistant soybean varieties combined with crop rotation

Combining SCN-resistant varieties with rotation to non-host crops (corn) reduces SCN population densities and extends the effectiveness of resistance genes.

What is a pre-emergent herbicide?

Answer: A herbicide applied to soil before weed or crop emergence to prevent germination

Pre-emergent herbicides are applied to soil before weed seedlings emerge, forming a chemical barrier that prevents germination or kills seedlings as they emerge.

The corn rootworm beetle's economic damage to corn is primarily caused by what?

Answer: Larval feeding on roots, reducing water and nutrient uptake and causing lodging

Corn rootworm larvae feed on corn roots, reducing the plant's ability to uptake water and nutrients and causing yield loss and lodging.

Which crop disease is caused by Fusarium graminearum and affects the heads of wheat and barley?

Answer: Fusarium head blight (scab)

Fusarium head blight (scab), caused by Fusarium graminearum, infects wheat and barley heads, causing yield loss and contaminating grain with mycotoxins like DON.