Agronomy Agronomy MCQ 5

Question 1

What is the main purpose of applying a pre-emergent herbicide?

Accepted Answer

Prevent weed seed germination after planting but before emergence

Answer

Pre-emergent herbicides form a chemical barrier in the soil that inhibits weed seed germination and early seedling growth before weeds emerge.

Question 2

In corn production, what is the 'critical period for weed control'?

Accepted Answer

V1 to V8 growth stages when weeds compete most for resources

Answer

Weeds emerging with corn during the V1–V8 period cause the greatest yield loss because they compete directly for light, water, and nutrients during early crop establishment.

Question 3

Which type of fertilizer application places nutrients directly in the root zone near the seed at planting?

Accepted Answer

Starter fertilizer (in-furrow or 2×2)

Answer

Starter fertilizer placed in-furrow or 2 inches beside and 2 inches below the seed supplies readily available nutrients to seedling roots in cool, wet conditions.

Question 4

What does the term 'lodging' refer to in cereal crops?

Accepted Answer

Premature stem breakage or root failure causing plants to fall over

Answer

Lodging occurs when cereal crop stems break (stem lodging) or roots give way (root lodging), reducing harvestability and grain yield.

Question 5

Which method is used to determine the lime requirement of an acidic soil?

Accepted Answer

Buffer pH test (e.g., Shoemaker-McLean-Pratt)

Answer

A buffer pH test measures soil's resistance to pH change and is used to calculate how much agricultural lime is needed to raise pH to a target level.

Agronomy Practice Test

Agronomy Practice Test

Agronomy Agronomy MCQ 5