Healthy Guavas Quiz Quiz

Explore key strategies, symptoms, and best practices for managing common guava diseases in horticulture. This quiz covers practical decision-making to help reduce crop losses and promote healthy guava orchards.

1. Identifying Anthracnose in Guavas

   What is the most common visible symptom of anthracnose on guava fruits in the field?

   1. Dark, sunken lesions with pinkish spore masses
   2. Galls or swellings on roots
   3. Yellowing and curling of leaves
   4. Powdery white spots on fruit surface

   Explanation: Dark, sunken lesions accompanied by pinkish spore masses are a classic sign of anthracnose in guava fruits, caused by Colletotrichum species. Yellowing and curling of leaves is more typical of nutrient deficiencies or viral infections. Powdery white spots suggest powdery mildew, not anthracnose. Galls or swellings on roots are usually associated with root-knot nematodes.

2. Cultural Control for Wilt Disease

   Which cultural practice best helps prevent the spread of guava wilt caused by Fusarium spp.?

   1. Applying high-nitrogen fertilizers regularly
   2. Removing and destroying infected plants promptly
   3. Irrigating heavily at night
   4. Planting guavas too close together

   Explanation: Prompt removal and destruction of infected plants reduces the spread of Fusarium wilt in guava orchards. High-nitrogen fertilizers can actually promote disease in some cases. Crowded plantings increase humidity and disease risk. Heavy nighttime irrigation may create moist conditions favoring pathogen growth.

3. Chemical Treatment Decision

   When signs of guava scab are detected on leaves and fruits, which type of chemical is typically recommended for management?

   1. Growth regulators
   2. Herbicides
   3. Systemic insecticides
   4. Copper-based fungicides

   Explanation: Copper-based fungicides are commonly used to manage fungal diseases like guava scab. Systemic insecticides control insect pests, not fungi. Herbicides target weeds rather than pathogens. Growth regulators influence plant development but do not address disease control directly.

4. Environmental Factors in Algal Spot Disease

   Which environmental factor most favors the development of algal leaf spot in guava crops?

   1. Cool, dry winds
   2. Extended drought periods
   3. Excessive soil salinity
   4. High humidity and frequent rainfall

   Explanation: High moisture from humidity and rain encourages algal growth on guava leaves, leading to algal spot outbreaks. Extended drought reduces moisture for algal proliferation. High salinity mainly stresses plants but doesn't directly increase algal spot risk. Cool, dry winds create unfavorable conditions for algal diseases.

5. Sanitation to Reduce Postharvest Losses

   Which method most effectively minimizes postharvest fruit rots in harvested guavas?

   1. Cleaning and sanitizing harvest tools regularly
   2. Mixing damaged and healthy fruits during packing
   3. Leaving fruits on wet ground for several hours
   4. Washing fruits with untreated canal water

   Explanation: Sanitizing harvest tools helps prevent the transfer of fungal and bacterial pathogens to healthy guava fruits, reducing postharvest rots. Leaving fruits on wet ground or using untreated water increases contamination risk. Mixing damaged with healthy fruits can spread infections rapidly postharvest.