Why do big cherries crack when it rains?

There are many reasons for cherry cracking. I hope to find out the corresponding situation from the following factors: \x0d\ 1. Varieties \x0d\ Some varieties have serious fruit cracking, and some varieties have certain expansion pressure due to the rapid fruit expansion in the later stage of fruit development, which leads to fruit cracking. The fruit cracking weight of Ukrainian series varieties such as Zaodaguo and choice is above 40%. Varieties with good pulp elasticity have light fruit cracking, and varieties with hard pulp have heavy fruit cracking, such as Hongyan and Redmi, while Brooks and Hongguang have heavy fruit cracking. The fruit with high fruit-setting rate is light, the fruit with low fruit-setting rate is heavy, and the trees with high fruit-setting rate provide relatively less water and nutrition per fruit, and the fruit expands slowly and cracks lightly, which is one of the reasons why the fruits with high fruit-setting rate mature late, such as Rabins, Xianfeng, Sato Jin, Renee and so on. \x0d\ 2。 Soil \x0d\ Sandy loam with loose soil and good drainage conditions has light fruit cracking, poor drainage conditions and heavy clay fruit cracking. Clay soil has poor permeability, and it is not easy to lose water after raining or watering, which increases the soil water content, and the water absorbed by the roots is transported to the fruit in large quantities, and the fruit cells crack due to water absorption and expansion. Well-drained sandy loam oozes water quickly after watering, and the soil is not easy to harden. The soil has good water retention capacity, and the root system absorbs water evenly, so it is not easy to crack fruit. For example, some sandy land, mountainous areas and plots with high organic matter content have slight fruit cracking. \x0d\ 3。 Moisture \x0d\ When the fruit is nearly ripe, it is submerged by rain or flood, and the soil moisture changes rapidly, and the water is transported to the fruit through the root system, which makes the pulp cells expand rapidly, and the swelling pressure in the fruit increases, which makes the peel burst and causes the fruit to crack. The rapid change of moisture content in the air can also lead to fruit cracking. If the air humidity in the greenhouse increases (more than 80%) due to cloudy days or rain at maturity, the humidity in the greenhouse drops sharply after sunny days or sudden air release, which will also cause a large number of fruits to crack. \x0d\ 4。 Weather \x0d\ When the fruit is ripe, the cracked fruit is light in sunny days and heavy in rainy days. \x0d\ 5。 Other reasons \x0d\ Low calcium and potassium content in fruits can also lead to fruit cracking. According to the determination, the sweet cherry with high calcium content cracked lightly.