How to control black spot of lettuce?

Lettuce is a vegetable whose stems and leaves can be eaten separately, some people like to eat leaves, some people like to eat stems, the taste is very refreshing. Lettuce is grown everywhere and is easy to manage, but it is vulnerable to diseases. Black spot is the most common disease in the growth of lettuce. How to prevent it?

First, how to control black spot of lettuce?

The pathogen of lettuce black spot usually appears in the diseased body in the soil, so that it can survive the winter. Generally speaking, black spot disease is easy to occur in rainy and humid weather, and once it occurs, it is more harmful to lettuce. In the environment with suitable temperature and humidity, lettuce black spot is easy to produce spores for infection and then spread through wind and rain. Especially when the soil fertility is not enough or lettuce grows slowly and weakly, it is especially easy to suffer from black spot.

In order to control the black spot of lettuce, it is mainly necessary for growers to strengthen their field management. When topdressing, choose organic fertilizer and phosphorus and potassium fertilizer, which can improve the disease resistance of lettuce. In addition, lettuce seed selection is also very critical, generally to choose disease-free, strong adaptability of excellent varieties. The seeds can be treated before sowing, which can improve the disease resistance of lettuce. Of course, the soil for growing lettuce is also critical, and crop rotation should be carried out. Usually, we should remove the old leaves and sick leaves in time, and then bury them deeply so as not to infect healthy plants. Once found that lettuce black spot, to use professional agents for spraying treatment, generally a course of treatment can play a very good effect.

Matters needing attention in the cultivation of lettuce

1. Choose the right variety

If you want lettuce to be high-yielding, you must choose suitable locally grown varieties, such as drought-resistant and heat-tolerant early-maturing varieties if you plant lettuce in summer and autumn. If you plant lettuce in winter and spring, try to choose varieties that are adaptable and cold-resistant.

2. Determine the sowing time

The sowing time of spring lettuce should be divided into greenhouse and open field planting. If planted in open field, it usually dies from February to March, and that in greenhouse is usually from December to March. If you plant lettuce in summer, you usually choose April to May. If lettuce is planted in autumn, it is generally chosen to sow seeds with sunshade net from July to September. If lettuce is planted in winter, it is usually sown from October to November.

3. Soaking seeds to accelerate germination

If it is summer to grow lettuce, the temperature is very high, so we have to choose cold water to soak the seeds and then sprout.

4. Sowing seeds

If the spring, summer and autumn are different, the main points of lettuce planting are also different. When sowing in spring, it is generally necessary to sow the seeds in the already moist soil after some fine sand. If you sow lettuce in summer, choose to sow on cloudy days. If you sow lettuce in autumn, remember to water the seedling bed thoroughly, then spread the base fertilizer and sow wet seeds.