- May 08, 2018 -
1. Control the shoots
Cherry branch buds growing.
Cherry buds can be divided into flower buds and leaf buds by their nature. The top buds of the cherry are the leaf buds, the side buds are the leaf buds, and some are the flower buds, which vary with the age and the growth potential of the shoots. Most of the lateral buds on saplings or wang shu are leaf buds, and most of the lateral buds on adult trees and on moderate growth or weak branches are flower buds. Cherry's sprouting power is stronger, but the cherry's branching force is different. Chinese cherry and sour cherry have strong branching ability, and sweet cherry has weak branching ability. Generally, 3 to 5 medium and long branches are drawn under the excision, and the rest of the buds have short branches or leafy branches. The few buds at the base do not germinate and become latent buds. Cherry saplings thrive, poorly controlled branches grow in the year, affect flower bud differentiation, tend to cause canopy closure, and postpone the outcome period. Due to the lower branching force of cherry, the lower buds are not easy to germinate, and the baldness of the lower branches tends to occur. The use of growth regulators can better control the growth of young trees, promote the formation of flower buds, and increase early yields.
Technical measures to control the growth of shoots
Paclobutrazol. The cherries were sprayed with paclobutrazol at 1-2g per square meter of the projected area of the tree crown before sprouting, or spraying paclobutrazol at the shoot growth rate of 200-2000mg/L. The sapling prolongation was well controlled and the florescence formation was improved.
PBO. For cherries, the shoot area of 5-10 g per square meter of the projected area of the crown before germination or 200-400 times of PBO for the shoots in the fast growing stage can better control the growth of young trees, promote the formation of flower buds, and increase the early yield.
2. Preserving fruit and keeping fruit before harvest
Reasons for low cherry fruit setting.
On the one hand, there is a great difference in self-cultivation ability between different types of cherries. Chinese cherry and sour cherry have a high rate of self-cultivation. They do not need to be equipped with pollination varieties and artificial pollination in production, and can still meet the requirement of high yield. The sweet cherries grew vigorously, the bouquet-like branches were difficult to form, and the self-pollination rate was very low. On the other hand, lack of water and fertilizer or improper fertilization. If the young cherry trees are applied with nitrogenous fertilizers, it may cause overgrowth, resulting in no flowering or fruitlessness of the tree of the right age, or flowering without fruiting. The nucleus softens and the peels yellow and fall off; In the absence of trace elements, especially in the absence of boron, the germination of cherry pollen grains and the formation and elongation of pollen tubes slow down, resulting in poor fertilization and flowering.
It has been observed that a large number of fruit drop of sweet cherries occurs mainly after 7-10 days after anthesis, 20-25 days after anthesis, and 10-15 days before preharvest. ABA can promote the formation of detachment and promote organ detachment, but the role of ABA is restricted by CTK, GA and IAA. Scientists believe that fruit drop is closely related to the ratio of ABA/(CTK+GAA+IAA) in fruit.
Technical measures to increase fruit setting rate and prevent pre-harvest fruit drop.
Gibberellin. Spraying 20-60 mg/L gibberellic acid every 10 days at full flowering stage, spraying twice, increasing fruit setting rate by 10%-20%.. Greenhouse cultivating cherry sprayed 15-20mg/kg gibberellin at the initial flowering stage, sprayed 0.3% urea and 0.3% borax at full flowering stage, and sprayed 0.3% potassium dihydrogen phosphate at young fruit stage, which was effective in promoting fruit setting and increasing yield. The 9-year-old red cherry sweet cherry sprayed 30-40 mg/kg of gibberellic acid at the flowering stage, significantly improved the fruit setting rate, and the fruit setting rate reached more than 50%. The application of gibberellin in combination with 6-BA increased the fruit setting rate more significantly than that of gibberellic acid alone. When 20mg/kg 6-BA was used in combination with 30mg/kg gibberellin, the fruit setting rate was as high as 56.9%, which was 6.8 percentage points higher than that of gibberellic acid alone, and 21.2 percentage points higher than the natural fruit set rate.
NAA. Chinese cherries are sprayed with 0.5-1mg/L naphthaleneacetic acid for 1-2 times before harvesting, and shoots and stalks can effectively prevent pre-harvesting fruit drop. However, when the concentration is too large, it can easily cause injury and cause a lot of small knots. The Rainier sweet cherry sprayed 40mg/L naphthylacetic acid solution 25 days before harvest to prevent pre-harvest fruit drop.
3. Promote fruit hypertrophy
Fruit growth and development.
The whole process of growth and development of cherry fruit can be divided into three periods: first-long-term, hard-core, second-long-term. Red cherry sweet cherry began to grow at full speed for a long period of time at I-speed. About 2 weeks, the fruit's vertical and horizontal diameters and single fruit weight increased rapidly, and its longitudinal growth was greater than its diameter. 15-25 days after flowering, it was a hard nucleus stage. The endocarp was lignified. The growth of embryo and endosperm was rapid. It competed with the growth of fruits for nutrients, and the vertical and horizontal growth of the fruit was slow. The increase in fruit weight was small. After 25-24 days after full bloom, it was the second longest speed, the fruit expanded rapidly, and the transverse diameter grew faster than the vertical diameter, and the single fruit weight increased rapidly. This time, the fruit growth accounted for about 2/3 of the total fruit weight.
Technical measures to promote fruit hypertrophy
GA3. At the beginning of the second-long-term growth period of Nongwon sweet cherry fruit, direct spraying of fruits and leaves with 10 mg/L GA3 solution resulted in a fruit weight increase of 61.43%, a 22.83% increase in fruit diameter compared to the control, and a soluble sugar content of the fruit juice increase13.93%. The uniformity of fruit and the degree of coloration were significantly better than the control. About one week after the ripening of the fruit was delayed, the red cherry fruit of 9 years old was uniformly sprayed with 10 mg/L GA3 on the 10th and 20th days after flowering, and the leaves were once sprayed. Compared with the control, the single fruit weight increased by 0.8g, soluble solid 2.13% increase in material content and 0.11% decrease in acid content. The fruit ripening period is concentrated on the 51st to 57th days after anthesis, 80% of the fruits are concentrated within 2-3 days, and the harvesting period is concentrated on 3-4 days, avoiding the drawbacks of split harvesting. For the sweet cherry topaz, the fruit was smeared with GA3 at a concentration of 60 mg/L 7 days after flowering. The vertical and horizontal diameters of the fruits before fruit ripening were greater than those of the control, and the fruit diameter was not significantly different from the control when the fruits were finally ripened.
The use of gibberellin in production should be determined based on the actual use time and the amount of use. Although spraying treatment can increase the single fruit weight, the treatment may cause the strain production in the following year to be significantly lower than the control. This may be related to the treatment of gibberellin to promote vegetative growth, thus inhibiting flower bud differentiation.
CPPU、KT-30. "Hongyan" sweet cherries sprayed once 5mg/L CPPU at full bloom, which could significantly increase the fruit weight of cherry. Spraying 5mg/L CPPU twice a week after 2 weeks also significantly increased the fruit number and promote coloring. The CPPU treatment with 10 mg/L spray at full flowering stage had an inhibitory effect on fruit growth. Nauvon sweet cherries sprayed 5-10 mg/L CPPU 13 d after flowering can significantly increase the weight per fruit and promote the coloration. The treatment with 10 mg/L concentration can also significantly increase the content of soluble solids. At the same time, it was found that 5 mg/L CPPU significantly increased the fruit cracking rate of Nauvon, while 20 mg/L CPPU treatment significantly reduced the cracking rate.
4. Prevent fruit cracking
Causes of cracking cherry fruit.
Cracking fruit seriously affects the quality of the fruit. Cherry fruit cracking is a kind of physiological disorder caused by fruit fragmentation when the fruit is close to maturity, when it rains for a long time or suddenly waters, because the fruit absorbs moisture to increase the turgor or the speed of the growth of pulp and peel is not uniform. The application of growth regulators and other technical measures can reduce the fruit cracking of the cherry fruit and improve the fruit quality.
Technical measures to reduce fruit cracking.
NAA. Spraying 1mg/L naphthalene acetic acid 30-35 days before harvest can reduce cracking caused by rain, and effectively reduce pre-harvest fruit drop.
CPPU. "Nauvon" sweet cherry sprayed 20mg/L CPPU 13d after flowering can reduce fruit cracking and promote coloration, but has little effect on single fruit weight, soluble solids, etc.