CCA Pest Diagnostics and Disease Management

Question 1

Which pathogen causes common corn smut, characterized by large galls on ears and tassels?

Accepted Answer

Ustilago maydis

Answer

Ustilago maydis is the fungal pathogen responsible for common corn smut, forming distinctive tumor-like galls on infected tissue.

Question 2

Soybean sudden death syndrome (SDS) is caused by which pathogen?

Accepted Answer

Fusarium virguliforme

Answer

Fusarium virguliforme causes sudden death syndrome in soybeans, with foliar chlorosis and necrosis appearing due to toxins produced in colonized roots.

Question 3

Wheat streak mosaic virus is primarily transmitted by which vector?

Accepted Answer

Wheat curl mites

Answer

The wheat curl mite (Aceria tosichella) is the primary arthropod vector responsible for transmitting wheat streak mosaic virus.

Question 4

Northern corn leaf blight (NCLB) lesions are best described as:

Accepted Answer

Large cigar-shaped grayish-green lesions parallel to leaf veins

Answer

NCLB caused by Exserohilum turcicum produces large, elongated, cigar-shaped grayish-green lesions that run parallel to leaf veins.

Question 5

Frogeye leaf spot in soybeans is caused by which pathogen?

Accepted Answer

Cercospora sojina

Answer

Cercospora sojina causes frogeye leaf spot, producing circular lesions with pale gray centers and reddish-brown borders that resemble a frog's eye.

(CCA) Certified Crop Advisor Practice Test

(CCA) Certified Crop Advisor Practice Test

CCA Pest Diagnostics and Disease Management