What are the symptoms of garlic soft rot, and how should it be prevented and controlled?

Garlic is one of the common seasoning foods in our daily lives, with a pungent taste, and eating it regularly is good for the human body. Garlic is cultivated in many places in our country, and during the growing process it is easily attacked by diseases, the common one being soft rot. So what are the symptoms of garlic soft rot? How to prevent and control it?

1. What are the symptoms of garlic soft rot?

Garlic soft rot is a bacterial disease and one of the main diseases on garlic, having a relatively large impact on yield and quality. Garlic soft rot occurs readily under low temperature and high humidity conditions, and is especially severe in soils that are low-lying, poorly drained, and have a high groundwater table. Strengthening field moisture management and keeping the soil dry can alleviate the condition. In years with little rain and in arid regions, the disease is generally milder. The disease mostly begins in November, occurring at the leaf margins or the midrib, forming yellow-white streaks along the midrib; when humidity is high, the diseased part becomes yellow-brown and soft-rotted, with yellow bacterial ooze appearing. The plant is affected first on the lower leaves and gradually spreads to the upper leaves; in mild cases only 2-3 leaves remain slightly green in the later stage, and in severe cases the whole plant withers, turns yellow and dies.

2. How to prevent and control garlic soft rot?

For garlic soft rot, the principle of integrated prevention and control should be adhered to, preventing the disease before it occurs. The main measures are as follows:

1. Select excellent garlic seeds, with virus-free, disease-resistant, pest-free and disease-free garlic seeds being the best.

2. It is advisable to choose flat terrain, convenient drainage and irrigation, soil rich in organic matter and with strong fertilizer and water retention capacity, and with a previous crop that is not of the onion and garlic type for planting garlic. Also prepare the land finely, achieving a loose top and firm bottom, so as to block the source of disease and avoid the conditions for its occurrence.

3. Apply sufficient well-rotted high-quality organic fertilizer and cake fertilizer based mainly on phosphorus and potassium fertilizers, to promote strong growth of seedlings, improve the disease resistance of the plants, and reduce the occurrence of physiological diseases.

4. Sow at the appropriate time, generally sowing before early October is advisable; after sowing, water thoroughly, and after watering cover with plastic film to raise soil temperature, preserve moisture and prevent drought, and promote the garlic seeds to sprout, emerge and grow healthily as early as possible.

5. Chemical control. Chemical control should do the following points well: (1) Seed garlic treatment: before sowing, dress and coat the seeds with 2.5% Shileshi suspension seed coating agent at 0.25% of the seed weight, which can kill the pathogenic bacteria on the garlic body; you can also dress the seeds with 50% carbendazim or 77% Keshade or 77% Duoning wettable powder. The seed dressing method is to dilute 100 grams of each agent in 5 kg of water, which can dress 50-75 kg of seeds; mix well and dry before sowing. (2) Soil treatment: this method is suitable for plots where soft rot has already occurred. You can spray the sowing furrow with 77% Duoning wettable powder 600 times dilution, spraying 100 kg of liquid per mu, and sow immediately after spraying; or mix copper sulfate, quicklime and plant ash in a ratio of 1:1:100 and broadcast it into the garlic furrow. (3) Chemical control: before the disease occurs or in the early stage of the disease, spray per mu with 72% agricultural streptomycin 3000-4000 times dilution, or 47% Jiaruinong 750 times dilution, or 50% Daisenammonium 1000 times dilution, etc., 50 kg, once every 5-7 days, and treat 2-3 times continuously depending on the condition. Focus spraying on mildly diseased plants and the plants around them, and be careful to spray the base of the plant stems. If diseased plants still appear after taking the above measures, you can promptly spray with 72% agricultural streptomycin wettable powder 400 times dilution, or 77% Keshade wettable powder 500-800 times dilution, 50 kg per mu, once every 7-10 days, spraying 2-3 times continuously; or use Xinzhimeisu 3000-4000 times dilution to drench the roots and stems.