Opinions on the Management of Spring Potato after the "late Spring Cold" disaster

The long-term low temperature and overcast rain since the beginning of spring, especially the severe low temperature from minus 3 degrees to minus 6 degrees on March 10, has had a serious impact on potato production. The stems and leaves of potatoes cultivated in the open air have been frozen to death, and the buds have also suffered varying degrees of frost injury. From the analysis of the degree of freezing injury, the cultivation in multi-span greenhouse is better than that in greenhouse, the cultivation in greenhouse is better than that of flat cover plus low bow cover, and the low bow cover of flat cover is better than that of flat cover. According to the preliminary analysis, the yield loss of spring potato will reach more than 20% because of the late spring cold, and the time to market will be delayed by more than 10 days. According to the current situation of the disaster, the author puts forward the following management suggestions: 1. Break the membrane and emerge seedlings in time. With the temperature rising and the climate of discontinuous rain, potato has entered the peak period of seedling emergence. It is necessary to break the membrane and emerge seedlings in time to prevent high temperature injury of seedlings, prevent frozen stems and leaves from rotting, and affect the growth of new buds. 2. Clear the ditch and drain the water. At present, the groundwater level of many potato fields is high, and the depression ditch is blocked, which is very disadvantageous to the growth of potato seedlings. We should pay close attention to clearing the ditch and desilting, so as to achieve the effect that the depth of the main ditch is 30 cm, the depth of the border ditch is 20 cm, and the rain stops the field to dry. 3. Use topdressing cautiously. Due to freezing injury, some farmers are only afraid of insufficient potato fertilizer and are prepared to apply topdressing after emergence. This kind of practice is not good. Because, at present, there is no shortage of fertilizer in potato fields, and topdressing can do more harm than good. In addition, topdressing can be applied only when the stem and leaf growth shows the symptom of lack of fertilizer. 4. Prevent frost injury of "late spring cold" again. Before the end of March, there is the possibility of another "late spring cold". If the freezing injury is serious, the consequences will exceed that of this one. Potato farmers should take precautions. Yesterday, the weather forecast showed that the day before the arrival of the afternoon, first, it could be covered with straw and other mulch in time, second, it was covered with low bow film, and third, it was sprayed with potassium dihydrogen phosphate 2-3 days before low temperature to enhance the cold resistance of the plant.