Why Does Honey Pomelo Crack? Detailed Explanation of Causes and Solutions
There are many varieties of honey pomelo and they are grown over a wide area, but because of differences in soil, temperature, humidity and other conditions, fruit cracking has become increasingly serious, especially in dry and poor orchards where the problem is particularly severe. So is there any way to reduce the incidence of fruit cracking in honey pomelo? Let's take a look together.
I. Causes of Fruit Cracking in Honey Pomelo
1. Water
During the fruit expansion stage of honey pomelo, prolonged drought, high temperatures and insufficient water supply cause the outer skin of the fruit to shrink. When heavy rain suddenly falls or large amounts of irrigation water are applied, the plant rapidly absorbs water, the flesh tissue absorbs too quickly and presses against the peel, while the peel cells absorb water more slowly and the peel layer is thin with poor elasticity, making fruit cracking very likely.
2. Nutrient Deficiency
Honey pomelo can also crack when it lacks elements such as potassium, calcium and boron. Applying excessive phosphate fertilizer while potassium fertilizer is lacking during the flowering stage of honey pomelo causes the peel to become thin and crack. Calcium is an important component of pectin, and pectin can increase cell wall strength and the hardness of the flesh tissue, reducing the rate of fruit cracking. Boron deficiency causes gummosis and shrinkage and rupture of the spongy layer, resulting in fruit cracking.
3. Improper Fertilization
If enough fruit-strengthening fertilizer is not applied, and there is excessive rain in the mid-to-late growth period of the plant with topdressing applied too late, the tree and fruit absorb large amounts of nutrients and water, causing uneven expansion inside and outside the fruit and resulting in cracking.
4. Improper Girdling
After girdling, the wound heals slowly, the transport of nutrients is blocked during the young fruit stage, and the growth of the young fruit is limited. After healing in the mid-to-late stage, the transport of nutrients suddenly increases, and this can also cause fruit cracking.
5. Hormones
The seeds and peel of honey pomelo can both produce gibberellin, but honey pomelo seeds are abortive or absent, so gibberellin cannot be produced normally, causing the peel and segments to grow at different rates, and the flesh and peel to grow and develop out of sync, making cracking very likely.
II. Solutions
1. Improve the Drainage and Irrigation System
A well-developed drainage and irrigation system should be established in the orchard, so that water can be applied promptly during high temperature and drought, and drained promptly during the rainy season, ensuring that the orchard soil stays within a suitable humidity range.
2. Leave Some Grass Appropriately
Some grass can be left appropriately in the orchard. This not only maintains soil moisture but also increases the soil organic matter content, improves the soil's buffering capacity for water, and reduces fruit cracking caused by the fruit starting to swell as cells absorb large amounts of water after rain.
3. Rational Fertilization
The proportion of organic fertilizer applied should be increased. The total amount of fertilizer applied during the plant's growth period should account for 80%-90% of the fertilizer applied over the entire fruit season. At the same time, the application of potassium, calcium and boron fertilizers should be increased, and as little fertilizer as possible or no fertilizer should be applied in the later stage.
4. Rational Girdling
Girdling is mostly carried out around the winter solstice, with a width of about 0.3 cm, cutting deep into the xylem without injuring the xylem. The girdling cut should be moved upward year by year, and 20 days after girdling the wound should be wrapped with black tape.
The above is an introduction to the causes of fruit cracking in honey pomelo and the solutions. We hope it can help you. To learn more related knowledge, please stay tuned to us.