Gibberella mainly harms the ear of wheat and will be infected at all stages of wheat growth. At the initial stage of scab infection, brown spots with waterlogging will appear on spikelets and glumes, and then gradually spread to the whole spikelets, and the spikelets will gradually turn yellow. In the late stage of the disease, a layer of mold with pink colloid will appear at the base of spikelet.
In fact, wheat scab is caused by a variety of Fusarium infection, and the pathogen of scab is highly pathogenic and widely distributed. The difficulty of invading pathogenic bacteria in different growth stages of wheat is different, and it is most susceptible to infection at flowering stage. In addition, under the condition of a large number of bacterial sources, if wheat encounters continuous rain for more than 3 days at the heading and flowering stage and the temperature is above 15℃, scab will be very popular.
The key to prevent and control wheat scab is to do a good job of spraying chemicals at heading and flowering stage and master the method of application. When spraying chemicals, we should focus on the uniform spraying of wheat ears. If it rains after spraying the medicine, it needs to be sprayed again after the rain. There are also disease-resistant varieties, so sow as early as possible to avoid rainy weather during flowering. Rational fertilization, increased application of chemical fertilizers, and coordination of nitrogen and phosphorus. Drainage should be done in time after rain to reduce the humidity in the field. And before sowing wheat, remove the residue of crops in the field and reduce the source of bacteria.
In addition, the seeds can be soaked in 50% carbendazim wettable powder with the mass of 0.2% of the seeds for 30 minutes, dried and sowed. The best application time is flowering period, and it should be applied at 10% ~ 50% flowering period. The preparation can be 50% carbendazim wettable powder 800 times or 70% thiophanate-methyl wettable powder 1000 times.