1. List the three damages

done by pests on crops
2. List three examples of
diseases transmitted by
insects to crops
3.Mention six effects of crop
pest on yield

1 answer

### Damages Done by Pests on Crops

1. **Physical Damage:**
- Pests such as insects and rodents can chew on stems, leaves, fruits, and roots, leading to physical damage that hampers plant growth and reduces yields.

2. **Nutrient Theft:**
- Pests like aphids and nematodes drain essential nutrients from plants. Aphids suck the sap while nematodes attack roots, both of which deprive crops of vital nutrients needed for growth.

3. **Disease Transmission:**
- Many pests act as vectors for various plant diseases, introducing pathogens (bacteria, viruses, and fungi) that can severely impact plant health and productivity.

### Examples of Diseases Transmitted by Insects to Crops

1. **Tomato Yellow Leaf Curl Virus (TYLCV):**
- Transmitted by the whitefly (Bemisia tabaci).

2. **Rice Tungro Disease:**
- Transmitted by leafhoppers (specifically the green leafhopper, Nephotettix virescens).

3. **Citrus Greening (Huanglongbing):**
- Transmitted by the Asian citrus psyllid (Diaphorina citri).

### Effects of Crop Pests on Yield

1. **Reduced Crop Quantity:**
- Physical damage and nutrient theft lead to a direct decrease in the quantity of harvestable produce.

2. **Lower Quality:**
- Infested crops often result in poor quality produce that may not meet market standards due to blemishes, deformities, or other pest-related damage.

3. **Increased Production Costs:**
- Farmers incur additional expenses in controlling pests through pesticides, traps, and other pest management techniques.

4. **Reduced Germination Rates:**
- Seed-eating pests can lower seed quality, affecting future crop yields by reducing germination rates.

5. **Delayed Harvest:**
- Severe infestations can stress the plants, leading to delayed growth and prolonged harvest times, disrupting planting schedules.

6. **Economic Losses:**
- The combined effects of lower yields, increased control costs, and decreased market value result in significant economic losses for farmers.