How to control the rotten heart disease of celery by the dry yellow rot of outer leaves and dark green leaves?

Celery "rotten heart" the main symptoms: celery outer leaves dark green, heart leaves dry yellow, rot. Rotten heart disease can occur in the whole growth period of celery, and the seedling stage is the most serious. In this paper, the causes and prevention measures of heart rot in celery are briefly described as follows:

Rotten heart with celery

First, the cause of the disease:

1. Calcium deficiency. Due to high temperature, drought, improper fertilization, high greenhouse temperature and lack of water, the root system of celery hindered the absorption of calcium, or too much nitrogen, potassium and magnesium in the soil hindered the absorption of calcium by celery.

2. Lack of boron and bad heart. The content of available boron in soil is low or celery can not absorb boron normally because of antagonism.

3. Bacterial soft rot. It mainly occurs on the base of celery petiole or stem, showing as water-immersed, light brown spindle-shaped or irregular sunken spots, and then wet rot, blackening and smelly.

4. Sclerotinia disease. First infect the base of petiole and rhizome of celery near the ground, the damaged part is water-immersed and rotten, when the humidity is high, white hyphae can be seen, and then the black sclerotia of mouse feces are formed.

II. Prevention and control measures

1. Cultivate strong seedlings. When raising seedlings, it is necessary to have time for seedlings to promote strong petioles and developed roots. Reasonable watering, to prevent excessive humidity, seedlings 3-4 leaves, dry and wet to promote root development. After planting and watering, follow-up watering should not be much.

2. Balanced fertilization, good control of temperature and soil moisture to prevent physiological calcium deficiency of celery can be prevented by foliar spraying 0.3% calcium nitrate solution mixed with 0.2% borax solution. At the same time, reducing the use of nitrogen fertilizer, especially ammonium nitrogen, potassium fertilizer can be appropriately increased, which is conducive to the absorption and utilization of calcium.

3. Chemical control.

(1) bacterial soft rot: 72% agricultural streptomycin or neophytomycin 3000-4000 times solution, 14% complex ammonia copper solution 300x, 77% can kill 500x solution or 47% plus Ruinong 600x solution can be used for control.

(2) Sclerotinia sclerotiorum disease: celery can be sprayed with 1500 times of 50% nonglidine, 1000 times of 50% trimethoprim, 50 times of carbendazim, 1000 times of isoniazide or 20 times of carbendazim.