Detailed Explanation of Garlic Disease Types, Causes, and Prevention and Control Methods

I. Types of Garlic Diseases

1. Round leaf (also called barrel)

This disease mainly manifests during the period before the garlic scape emerges; the leaves at the top of the garlic form a barrel shape that tightly wraps the garlic scape inside the barrel, causing the scape to become enclosed or broken.

2. Garlic branching

That is, multiple branches on one plant, like grandfather and grandson, with nutrients dispersed; the main garlic scape lacks sufficient nutrients and is thin and short.

3. Spots

This disease mainly manifests before the garlic scape bolts; spots appear on the surface of the garlic scape, including white spots, yellow spots, and red spots, causing the garlic scape to rot or become moldy.

4. Garlic glume turning red or flowering

The glume of a good garlic scape is green and does not flower, whereas a diseased garlic scape, as soon as it bolts and before it bends down, has its glume turn red and flower.

5. Leaves turning yellow, withering, and dying

This is a relatively serious disease of garlic. Once this disease appears, it will spread and expand, and may even cause large patches or entire patches to wither and die.

II. Causes of Diseases

Garlic has many types of diseases and suffers huge losses. The main root causes of these diseases are as follows:

1. Aging of garlic seed. It is understood that in some places, since the household contract responsibility system was introduced, or even earlier, garlic farmers still use the garlic seed from that time, planting year after year; no matter how they plant, it is still the old garlic seed, with variety aging and degeneration and more diseases.

2. Aging soil and more residual pathogens. Most garlic farmers, due to reasons such as little land or irrigation, replant continuously year after year; they plant corn in garlic fields and plant garlic in corn fields, such a vicious cycle means the land cannot be deep-plowed, weeds grow in abundance, and pests and diseases are extremely numerous.

3. No organic fertilizer. In particular, no organic fertilizers such as pig manure and chicken manure, causing the soil to harden and compact, and the degree of salinization to worsen.

4. There are few pesticides for preventing and controlling garlic diseases, and they cannot meet or keep up with the needs of the occurrence and development of garlic diseases.

III. Fundamental Solutions and Countermeasures

1. Agriculture-related departments should serve garlic farmers, actively purchase and introduce high-quality garlic seed, strictly control garlic seed quality, and do a good job in updating and replacing garlic seed and optimizing varieties.

2. Do a good job in crop rotation to prevent soil aging. Garlic planting plots should be adjusted and changed frequently, and must not be planted continuously without change.

3. Deep-plow the land to reduce weeds, pests, and pathogens. Deep plowing can bury weeds, pests, and pathogens remaining on the soil surface deep underground, achieving the purpose of sterilization and pest elimination.

4. Spray pesticides in a timely manner to prevent and control pests, ensuring that garlic grows normally without being affected by pests and diseases.

5. Apply more organic fertilizer, especially pig manure and chicken manure, to keep the soil loose and soft, and provide a high-quality ecological environment for the good growth of garlic.