Prevention and treatment of heart leaf browning tissue rot and malodorous pineapple heart rot

Pineapple heart rot often occurs in pineapple orchards shortly after planting. Once the disease occurs, it spreads rapidly and loses a lot. Occurrence and control of pineapple heart rot:

Pineapple heart rot

Symptoms: pineapple heart rot is mainly harmful to seedlings and adults. The leaves of the damaged plants were green at the initial stage, only the leaves were slightly dark and dull, and the heart leaves were yellow and white, easy to pull up and not easy to detect. After that, the leaf color of the diseased plant gradually faded green to yellow or red to yellow, the leaf tip became brown and dry, the leaf base rotted in the shape of light brown water stains, the decaying tissue softened into cheese, and the junction of the diseased part was dark brown. Due to the invasion of secondary bacteria, the rotten noodles smelled and the whole plant withered.

2. Pathogens: it is generally believed that there are three kinds of pathogens of heart rot, including two kinds of pathogenic fungi, namely Phytophthora, Pythium, and one kind of pathogenic bacteria, that is, Eucella.

Third, infection cycle: two kinds of pathogenic fungi can survive the winter in the soil, and the pathogenic bacteria can be transmitted by bacteria-carrying insects. The pathogen invaded from the young part of the root-stem junction (root neck) of pineapple, causing the disease. Bacteria spread by Rain Water sputtering, repeated infection, the disease was able to spread.

4. Epidemic conditions: 1. In the high temperature and rainy season, especially after planting in autumn, the disease is often more serious. 2. The pineapple orchard with heavy clay, poor drainage and easy waterlogging is more serious.

5. Prevention and control methods:

1. The disease occurs seriously in rainy season, especially shortly after planting, so strong seedlings must be selected before planting, and then seeded after a certain drying period. Pay attention to drainage and avoid planting in low-lying, wet places.

2. Before planting in the disease area, the seedlings should be treated by peeling off a few leaves at the base of the seedlings, then soaking the base of the seedlings with 25% carbendazim wettable powder for 15 minutes, and then planting them after being inverted to dry.

3. Avoid leaf base injury and be careful when ploughing and weeding.

4. Rational fertilization, do not partial application or over application of nitrogen fertilizer.

5. At the beginning of the disease, 50% carbendazim wettable powder can be sprayed with 1500 times of carbendazim or 1000-500 times of methyl topiramate or 1500 times of 50% carbendazim wettable powder (about 125kg per mu) to prevent the spread of the disease. The diseased pineapple seedlings should be pulled out and burned in time. The diseased soil should be removed, replaced with new mud, then disinfected with lime, and then replanted with good seedlings.