Prevention and control of fruit cracking in mature period of pomegranate

I. planting varieties resistant to cracking

This is the fundamental measure to prevent fruit cracking. The development of pomegranate should give priority to this measure. The excellent varieties of pomegranate Zhongheyin copper red pomegranate, Heyin moon white pomegranate, Heyin red lantern pomegranate, Tunisian soft seed pomegranate and super large seed pomegranate are all resistant to cracking fruit, and Taishan red pomegranate is also more resistant to cracking fruit, but the quality is not as good as the above varieties. Lintong Tianhong egg, Dahongtian, Pink Tiantian, Yu pomegranate 1, Yu pomegranate 2, Yu pomegranate 3 were all resistant to cracking. The pomegranate orchard which has been planted with easy-cracking fruit varieties can be changed into crack-resistant fruit varieties through high grafting and head-changing technology.

Second, choose high and dry places to develop pomegranate trees.

Practice has proved that if the terrain is high and dry, the fruit will crack lightly; if the terrain is low-lying and stagnant water, the fruit will crack seriously.

Third, apply more organic fertilizer and complete fertilizer

The cracked fruit of such pomegranate trees is very light or non-dehiscent, and the cracked fruit of pomegranate trees applying special fertilizer for fruit trees is also light, while that of pomegranate trees applying nitrogen fertilizers such as ammonium bicarbonate and urea is severe. Therefore, in pomegranate orchard fertilization, priority should be given to high-quality farm manure, such as cow manure, sheep manure, chicken manure, pigeon manure, horse manure, pig manure, straw manure and all kinds of green manure. Even if chemical fertilizer is applied, it is best to choose special compound fertilizer for fruit trees or high-quality three-element compound fertilizer of nitrogen, phosphorus and potassium. Especially in the later stage of fruit development, do not apply nitrogen fertilizer.

Pay attention to watering and water control

In the early stage of pomegranate fruit development, from May to July, when the weather is dry, the pomegranate fruit should be watered in time to promote fruit cell division. About a month before maturity, as long as the weather or soil is not too dry, try not to water, even if it is too dry, you should also water a small amount of water. Watering before ripening is an important reason for pomegranate fruit cracking, especially in the early and late drought period, Rain Water or watering fruit cracking is more serious.

Fifth, spray calcium on trees

In the process of pomegranate growth and development, spraying 2 ~ 3 times of calcium chloride, calcium nitrate or other organic calcium fertilizer can reduce fruit cracking, and the effect is obvious. But it can not completely eliminate the dehiscence.

VI. Fruit bagging

Bagging is a better way to prevent fruit cracking. The effect of double-layer special fruit bag (such as Kobayashi apple bag in Japan) is the best, and the effect of plastic bag is also better. In order to finish the cover before June 1, the whole tree was carefully sprayed once before bagging with Dasheng MMI 45 fungicide 800x mixed with 2000 times of thiazuron 3, in order to eliminate pomegranate fruit pathogen and peach borer and other diseases and pests.

7. Cultivation for shelter from rain

Build a rain shelter at the top of the orchard, but there is air all around. This is a good way to prevent fruit cracking, especially suitable for the cultivation of precious varieties with high economic benefits.

VIII. Timely harvest and early harvest

The pomegranate ripens early in mid-August and late in mid-October. Therefore, it should be harvested timely according to the maturity of each variety. Because the growth and development of pomegranate grain does not stop before defoliation and grows every day, so it is harvested too late, even the varieties that are resistant to cracking will have fruit cracking. Varieties that are not resistant to cracking should be picked early or harvested ahead of time. Although early harvest will reduce the quality, this is a last resort. Early harvest is better than late harvest.

9. Keep the tree mediocre and strong

Practice has proved that the cracked fruit of the moderate and strong pomegranate tree is light, while the cracked fruit of the overgrown pomegranate tree is heavy. It should be realized through various cultivation measures, such as soil improvement, regulation of fertilizer and water, shaping and pruning, etc.