1, the symptoms of the disease
Heartburn, also known as heart rot, mainly harms the heart. In the early stage of disease, the soft tissue of the heart-leaf growing point changed from green to brown, and then extended to the heart and leaves with coke. Subsequently, the celery root and some stems and leaves also died one after another. The disease rarely occurs in the early stages of childbirth and begins to occur when 11 to 12 true leaves are present.
2, the cause of the disease: celery heart disease as a physiological disease, caused by plant calcium deficiency. The content of calcium and boron in the soil is lacking; the concentration of salt in the soil is too large, causing calcium absorption difficulties; in the case of drying, excessive nitrogen fertilizer causes difficulty in root absorption of boron, resulting in insufficient absorption of calcium and other reasons, can cause burning Heart disease. Encountered a humid environment, high temperature and humidity, long-term continuous rain, soil moisture, the heart will be infected by bacteria
3, suitable for the susceptible environment
Many years of continuous cropping or low-lying plots with poor drainage, excessive nitrogen fertilizer and potassium fertilizer, excessive plant growth, high salt concentration in the saline or alkali soil or soil, high temperature, low temperature and drought, resulting in inhibition of absorption of boron and calcium by celery , And produce heart rot. Because of the lack of boron in the plant, calcium can not be absorbed normally and cause heart rot.
4. Control methods
(1) Adopt soil testing and formula fertilization to adjust the content of elements such as nitrogen, phosphorus, potassium, boron and calcium in the soil; 0.3% to 0.5% calcium nitrate solution may be sprayed on the onset.
(2) Select high-drying non-saline alkali fields, use deep-groove sorghum cultivation, do not flood flooding; reuse farmyard manure to improve soil; nitrogen, phosphorus, potassium and trace elements should be used scientifically; cool down at high temperatures, To keep warm at low temperature, apply proper amount of dry lime when turning to the ground; use aseptic soil for nursery soil and use it for more than three weeks before drying; properly close planting, remove diseased leaves and diseased plants in time, and bring them out of the field. Burned, sickly or lime.
(3) Control medication: 300-400 times of superphosphate, 300 times of calcium chloride, or 400 times of 0.1% calcium nitrate sprayed on the leaves of celery 5-8 leaves, once every 15 days, spray 2 - 3 times. The rot of the heart caused by the humid environment can be sprayed with an appropriate amount of bactericide at the same time as the phlegm is discharged.
3D Face Mask,Face Mask 3D Model,3D Disposable Face Mask,3D Disposable Mask For Adults
KUTA TECHNOLOGY INDUSTRY CO.,LIMITED , https://www.kutasureblue.com