How to prevent pear blackheart disease?

How to prevent and cure the black heart disease of Yali pear? Please guide that black heart disease is a physiological disease of Yali pear during storage. Yali pear can occur after storing in 0 ℃ cold air storage for 50 days. Brown plaques can be found in the pericarp of the fruit at the initial stage, and gradually spread to the whole core. In severe cases, the pulp part will also appear undefined browning, the flavor will become worse, and there is generally no obvious reaction in the appearance of the fruit. However, it greatly affected the storage time and quality of Yali pear. There are four main reasons for the black heart disease of Yali pear: first, the chilling injury caused by the low temperature (0Mu5 ℃) in the early stage of storage, resulting in cold-damaged core browning. Second, the postharvest fruit is placed under unsuitable environmental conditions for too long, which makes the fruit begin to senescence in the early stage of storage, or the temperature is too high and the humidity is too low during storage, which makes the fruit lose water seriously, which will lead to aging black heart in the later stage of storage. Third, excessive application of nitrogen fertilizer before fruit harvest, lack of calcium and phosphorus fertilizer, resulting in calcium deficiency black heart in the later stage of storage. Fourth, when the concentration of carbon dioxide exceeds 2% during storage, black heart disease will also occur. The methods to prevent and cure the black heart disease of Yali pear are as follows: 1. The application amount of nitrogen fertilizer should be controlled in the later stage of fruit growth, and attention should be paid to the application of calcium and phosphate fertilizer. during the growth period, 0.2% Mel 0.3% calcium nitrate can be continuously sprayed on the fruit for 4 times. 2. After the fruit is harvested, soak the fruit with 2% Murray 4% calcium chloride for 5 minutes, which has a better control effect. 3. It should be stored in time after harvest in order to reduce the respiratory intensity of the fruit and delay the senescence of the fruit, and the method of slow cooling should be adopted to prevent the occurrence of cold injury black heart disease. After storage, the fruit was pre-cooled at 7 ℃ for 10 days, then decreased by 1 ℃ every 3 days, and then decreased to 0 ℃ after 20 ℃ 30 days, then long-term storage, and pay attention to control the concentration of carbon dioxide, strengthen the ventilation of the storage, so that the concentration of carbon dioxide in the storage environment was reduced to less than 1%. Click for more pear tree planting techniques click to get more fruit planting techniques