Symptoms: generally, the disease starts from late March to early April. At the beginning of the disease, the plant symptoms are not obvious. Then, with the aggravation of root rot, the new leaves gradually turn yellow. At the later stage, the leaves of the whole plant begin to turn yellow and wither, and even the whole plant dies.
Prevention and control: disinfect the seeds before sowing to avoid infection. Usually, we should control the amount and time of watering to avoid ponding. In the early stage of the disease, 50% carbendazim can be sprayed, once every 10 days or so, 2-3 times in a row.
Symptom: it will harm the stem, especially in high temperature and humidity environment. After the disease, the cortex tissue of the stem will rot, showing some gray white spots, then spreading the whole plant, later the disease becomes serious, the disease part presents dark brown dry rot, and finally leads to the dry leaf or death.
Prevention and control: pay attention to ventilation, reduce planting density, apply fertilizer reasonably, and improve disease resistance. If the plant has been sick, spray a little Bordeaux at the beginning of the disease, once every 3-5 days.
