What should apple trees pay attention to when thinning flowers and fruits?

In the process of apple planting, the load of apple trees is adjusted by thinning flowers and fruits, especially when there are many fruits in the new year. Although the yield is high, but the quality is not high, thinning flowers and fruits is a necessary means to improve the high yield and quality of apples. So what should apple pay attention to when thinning flowers and fruits?

First, the thinning of flowers during the budding and flowering period of apples

The flowering time of apples varies with varieties, tree age, fruit branch type and flower bud quality. In the same area, Zhuguang and India bloom earlier, Guoguang is the latest, and other varieties are in between. Adult trees bloom earlier than young trees, and strong trees grow earlier than weak trees and weak trees. The flowering period of different branches on the same tree is also different. Short fruit branches are the earliest, medium-long fruit branches are the later, and axillary flower buds are the latest. On the same tree, flowers that bloom early have good quality, high fruit setting rate and good fruit development.

The thinning of apple flowers is from bud division to flowering. The fruit setting rate of varieties is high, and when flowering conditions are good, flowers can be thinned and fruit set artificially. The specific approach is:

According to the tree potential, variety, flower quantity, etc. , 1 inflorescence with suitable position is kept at a distance of 20-25 ㎝ (the bigger the fruit type, the farther the spacing is). During bud separation, each inflorescence is kept with 1 central flower and 1-2 lateral flowers.

The advantages of this are:

Save a lot of storage nutrients, improve the fruit setting rate of flowers by more than 95%, the first-class fruit rate and the super-class fruit rate by more than 85%, and obviously improve the fruit quality. Clear vision, labor-saving, fast progress, one step in place, not easy to miss, avoiding repeated work of fruit thinning. This method must meet the following conditions:

The layout of pollination trees in the garden is reasonable, and there are enough conditions for bee pollination or artificial pollination; The tree body is robust, the flower buds are full, the flower organs are normal, and there is no low temperature injury and insect pests; After careful pruning in winter, the proportion of flowers to leaves and buds is reasonable, and the branches are relatively thick. When the flowering climate is unstable and the fruit setting is unreliable, leave room and leave more inflorescences and buds at an appropriate distance.

Secondly, fruit setting and fruit thinning during the development of apple fruit.

1, determine the target output.

At present, apple's production capacity is saturated, especially this year's apple price plummeted, which seriously hit the enthusiasm of fruit farmers. Therefore, limiting yield and improving quality have become the main technical measures to increase income, and trying to reduce yield and improve apple quality. According to the actual situation of the orchard, the specific target yield should be determined in the thinning scheme.

2. Select the thinning method

Because of the strong seasonality of flower thinning and fruit thinning, the traditional manual flower thinning and fruit thinning is not only time-consuming and laborious, but also difficult to complete in a short time. Therefore, many fruit farmers use chemical thinning, but it often has different degrees of adverse effects on the fruit. Therefore, it is suggested to use chemical thinning as an auxiliary means of artificial thinning to complete the necessary thinning amount. ~? In production, manual thinning is still needed.

3. Choice of fruit thinning time

The suitable thinning period mainly depends on two contradictory factors: safety, accuracy and nutrient saving. In terms of saving nutrients, flower thinning is better than fruit thinning, and flower bud thinning is better than flower thinning, but the earlier flower thinning, the more uncertain factors. Therefore, under the premise of ensuring safety, effectiveness and accuracy, early dredging is appropriate.

The first fruit thinning period is usually 10 day after flowering, and the first fruit thinning is carried out in mid-May to remove the fruit shape, insect fruit and top fruit, and keep the central fruit.

The second fruit thinning period is 4-5 weeks after flowering, and the time is about early June. This time it is small fruit, crooked fruit, flat fruit, deformed fruit, fleshy fruit, upside down fruit, diseased fruit, damaged fruit and so on. Thinning should be done to keep drooping fruits, and then the yield should be determined according to the trees and the remaining fruits should be determined.

4. Determine the load of each device

According to the previously determined target yield and the specific growth of apple trees, the yield and the number of fruits left per tree are determined.

(1), Qiao Hua rootstock:

Large fruit: the fruit spacing is 20~30㎝, leaving a single fruit; Medium-sized fruit: fruit distance 15~25㎝, mainly single fruit, combined with double fruit. (2) Dwarfing intermediate rootstock trees and short branch trees

Large fruit: the fruit spacing is 20~25㎝, leaving a single fruit; Medium-sized fruit: fruit distance 15~20㎝, leaving a single fruit. 5, fruit thinning measures

(1), according to the leaf thinning ratio.

Dwarf rootstock and short-branch apple have strong assimilation ability, and the leaf-fruit ratio is 40:1; The leaf-fruit ratio of ordinary large-size apples such as Fuji series is 60: 1.

(2) Fruiting according to the top bud of the tree.

Small fruit varieties, such as Guoguang and Pink Lady, keep one fruit in three terminal buds; Big fruit Fuji, Jonathan and other four terminal buds leave one fruit.

(3) Preserve the fruit according to the distance

For large fruits, the distance between fruits should be large, otherwise it should be small. Generally, the distance between Fuji series and other large fruits is 20 ~ 25 ㎝; Miss fruit powder is 15~20㎝.

Distance fruit preservation method is more commonly used. The order of fruit thinning is from top to bottom, from inner chamber to periphery. In order to prevent leakage, branches can be distributed from top to bottom in the order of natural distribution, and each branch can be carried out from inside to outside; As far as an orchard is concerned, for varieties with early flowering and low fruit setting rate, thinning should be carried out first according to the flowering time and fruit setting of varieties, which can generally be carried out in turn according to Marshal, Jonah, Tianjin, Jinguan and Fuji. Within the same variety, first sparse big trees, weak trees and big trees with many flowers and fruits. Fruits should be drooping fruits and fruits with drooping lateral branches. The fruit shape should be straight, piled high, free from pests and diseases, with flat shoulders and long stalks.

After the whole tree is drained, it should be carefully checked around the tree for a week to check the total amount of fruit left in the whole tree, and the missing part should be supplemented in time.

As an important means of apple planting management, thinning flowers and fruits has created necessary conditions for saving nutrition, improving fruit color and sugar content, increasing fruit size and promoting flower bud differentiation, and laid a foundation for improving fruit quality in the later stage.