What Are the Causes of Calcium Deficiency in Apple Trees? A Full Analysis of Prevention and Control Measures
The apple is a very common fruit and is widely distributed throughout our country. When growing apples, the nutritional demands of the apple tree are very high. If nutrients are lacking, nutritional deficiency is likely to occur. This is especially true of the various secondary and trace elements, among which calcium is even more important. Calcium deficiency in apples has a very large impact on both yield and quality. So what causes calcium deficiency in apples? And how should it be prevented and controlled? Let's take a look below!
1. Causes of Calcium Deficiency
1. Soil calcium deficiency
Calcium ions move and are transported very slowly within the apple tree, so it is very slow for the apple tree to replenish calcium from the soil. The transport of calcium ions in the xylem of the fruit tree mainly occurs through evaporation from the leaves; in mature leaves, transpiration is relatively strong, so calcium is relatively abundant. But for terminal buds, weak buds, and branches on the lower part of the tree with poor light conditions, transpiration is weak, so calcium is scarce. Furthermore, the transport of calcium ions in the phloem is very poor, and the calcium in mature leaves cannot be used by young leaves, root tips, and fruit. Therefore, when apples are deficient in calcium, it first shows up in the root tips, growing points, and fruit.
2. External causes
When fertilizing, if chemical fertilizers are applied over the long term, the available secondary and trace elements in the soil will be depleted, causing severe calcium deficiency in the soil. Or, if large amounts of nitrogen, phosphorus, and potassium fertilizers are applied, this will also inhibit the fruit tree's absorption of calcium. In addition, if the soil is severely dry and the soil moisture content is below 50%, the leaves will gradually wilt, thereby weakening transpiration and blocking the transport of calcium ions. At the same time, waterlogging caused by excessive accumulated water will also lead to calcium deficiency. Finally, before apple harvest and during the rapid fruit enlargement stage, if there is insufficient light and prolonged rainy weather, this will likewise affect calcium ions and cause calcium deficiency symptoms.
2. Prevention and Control Measures
1. Rational fertilization
When fertilizing, we must be sure to control the amount of chemical fertilizer applied. When applying base fertilizer in autumn, farm machinery manure and some high-quality organic fertilizers should be the main inputs. At the same time, the amount of fertilizer applied must be controlled; generally, about 40kg of silicon-calcium fertilizer is applied per mu. Using fertilizer to increase the content of organic matter and secondary and trace elements in the soil improves soil fertility. However, because calcium ions are transported very slowly within the fruit tree, there may not be very obvious results in the same year. But as long as application is continued every year, the problem of calcium deficiency in apple trees can be fundamentally solved.
2. Other measures
During the first root growth peak of the apple tree in March, apply an appropriate amount of calcium nitrate to the soil. Then, during apple bud break, the flowering stage, and the young fruit stage, spray an appropriate amount of chelated liquid fertilizers such as amino acid calcium onto the leaves, which has a significant calcium-supplementing effect. Then prune appropriately to provide the fruit tree with a good light environment. If the soil is dry, water it in a timely manner to keep the soil's maximum field water-holding capacity at around 65%. Finally, thicken the soil layer under the canopy, build good drainage ditches, and drain promptly during the rainy season.
The above is a brief introduction to the causes of calcium deficiency in apples and the prevention and control measures. That is all for today's introduction. This article is for reference only, and I hope it can help everyone!