Defeat the Root Fungus! Quiz

Explore effective and scientifically sound strategies for managing root diseases in horticultural systems, focusing on prevention, identification, and treatment. Strengthen your understanding of root health and disease control methods for thriving crops.

1. Recognizing Symptoms

   Which symptom is most characteristic of root rot caused by fungi such as Phytophthora in vegetable crops?

   1. Yellowing leaves with powdery spots
   2. Wilting and darkened, mushy roots
   3. Angular leaf spots with yellow halos
   4. Leaf curling without any visible root damage

   Explanation: Wilting and mushy, dark roots are typical of root rot, as the pathogen destroys the root tissue. Yellowing leaves with powdery spots usually indicate powdery mildew. Angular leaf spots are often caused by bacterial infections, not root fungi. Leaf curling without root damage is generally linked to viral or abiotic stress, not root rot.

2. Crop Rotation Benefits

   How does crop rotation help reduce the risk of soil-borne root diseases in horticultural fields?

   1. Lowers soil pH to kill most fungi
   2. Directly kills pathogens with sunlight
   3. Increases fertilizer uptake in roots
   4. Interrupts pathogen life cycles by changing plant hosts

   Explanation: Crop rotation helps interrupt pathogen cycles by depriving them of their preferred hosts, reducing disease pressure. Lowering soil pH doesn't generally combat most root fungi. Sunlight does not penetrate the soil enough to directly kill pathogens. Fertilizer uptake may help plant vigor but does not directly impact pathogens.

3. Cultural Practices

   A horticulturist notices persistent root disease in a greenhouse. Which practice can MOST effectively lower disease risk?

   1. Applying nitrogen fertilizers exclusively
   2. Improving soil drainage
   3. Watering late in the evening
   4. Increasing planting density

   Explanation: Good drainage reduces waterlogged conditions where root pathogens like Pythium thrive. Watering late encourages leaf and soil moisture overnight, promoting disease. High planting density increases humidity and root contact, favoring spread. Excessive nitrogen alone does not control root pathogens and may worsen susceptibility.

4. Chemical Controls

   When should chemical fungicides be considered for managing root diseases in horticultural crops?

   1. Only after visible leaf blight appears
   2. For every crop, preventatively at all times
   3. When planting drought-tolerant varieties
   4. As part of an integrated plan when other measures fail

   Explanation: Fungicides should be used judiciously if cultural and biological methods do not suffice, as part of integrated management. Routine, indefinite use can cause resistance and environmental harm. Waiting for leaf blight is too late and unrelated to root diseases. Drought tolerance in crops does not obviate root disease risk.

5. Biological Control Option

   Which of the following is a biological approach to managing root diseases in horticulture?

   1. Pruning fruit after harvest
   2. Using plastic mulch as a weed barrier
   3. Applying beneficial microbes like Trichoderma
   4. Sterilizing soil with high heat

   Explanation: Beneficial microbes such as Trichoderma compete with or antagonize soil-borne pathogens biologically. Soil sterilization with heat is a physical, not biological, control. Plastic mulch blocks weeds and conserves moisture but does not directly combat root diseases. Pruning fruit is unrelated to root health.