Key points of whitening technique of winter jujube

Reasonable water and fertilizer: when jujube fruit enters the white ripening stage, potash fertilizer can be increased, nitrogen fertilizer can not be applied, young and weak trees should be watered less, and strong trees and mediocre trees should not be watered. Manage nail mouth: weak nail mouth has not healed, can use cytokinin smear, and then use plastic to bind nail mouth, has healed nail mouth, prosperous tree and mediocre tree can carry on the second opening, weak tree should not open. Promote color change: Guoguang potassium can be mixed with Guoguang days for foliar spraying. Greenhouse cooling: cover sunshade net during high temperature period.

The whitening technology of jujube determines the coloring effect of jujube fruit in the later stage of winter jujube. the white ripening stage of winter jujube refers to the decrease of chlorophyll content in pericarp cell, the background color of pericarp fades and becomes whitening, and the pulp of jujube fruit is gradually soft. therefore, mastering the key points of whitening technology plays a key role in the coloring and ripening of jujube fruit in the later stage.

1. Rational water and fertilizer

1. Jujube fruit enters the white ripening period, during this period, the accumulation of sugar and dry matter will be accelerated, potassium fertilizer should be increased, nitrogen fertilizer should not be applied, because nitrogen fertilizer can easily lead to late ripening of jujube fruit, thus delaying ripening time, and fertilizer gun can be used to fertilize. About 5-8 kg of Guoguang potassium can be applied per mu.

2. In the white ripening period, the seedlings can be watered appropriately according to the specific growth conditions of the seedlings, young trees and weak trees can be watered a small amount, strong trees and mediocre trees can not be watered, such as excessive watering will cause jujube fruit greasy green, thus affecting the ripening time.

Second, manage the first mouth

1. After the winter jujube enters the white ripening period, the management of the nail mouth must be strengthened. if it is found that the nail mouth has not healed, it should be dealt with in time, gibberellic acid and cytokinin can be smeared on the nail mouth, and then the nail mouth can be tightly bound with plastic film.

2. If the nail mouth has healed, the second armour opening can be decided according to the specific tree potential. Both the mediocre tree and the prosperous tree can carry out the second armour opening, and the width of the armour mouth can be determined according to the tree potential and the amount of fruit hanging. It is not suitable to cause the death of the tree. Weak trees can be cut many times by ring cutting every 5-7 days, not twice.

Third, promote color change

The speed of green fading of jujube fruit directly affects the color speed of jujube fruit in the later stage. in order to promote the whitening of jujube fruit background color, Guoguang potassium mixed with Guoguang Tian can be used for leaf spraying, spraying every 7-10 days, 2-3 times successively, which is beneficial to improve the smoothness of fruit surface and increase the content of sugar and dry matter in jujube fruit.

Fourth, greenhouse cooling

If the temperature in the shed rises in case of high temperature, which will affect the normal growth of jujube fruit, corresponding cooling measures should be taken. According to the local climate, a layer of shade net can be covered during the high temperature period, or mud can be sprinkled to cool down. However, it is not easy to spray evenly, long-term coverage affects photosynthesis, such as Rain Water is easy to be washed away.

V. Prevention and control of diseases and insect pests

Jujube fruit in the white ripe period, such as high humidity and high temperature climate, is easy to cause diseases and insect pests, such as fruit cracking, charcoal maggot disease, fruit shrinkage disease, etc., can be controlled by tebuconazole, promethrin, thiophanate methyl, pyrazolyl, prochloraz, prochloraz, etc., the main pests are heart borer, red spider, jujube tick, etc., you can choose methylovir salt, spiromites, pyrethroids, avermectin and so on.