Why do you say "full of flowers and half fruits, half flowers and half fruits?"

The farmer's proverb says, "Half a tree is full of flowers, and half a tree bears fruit." .

This is a correct summary of the relationship between flower quantity and fruit quantity of fruit trees by the ancients. It means that the fruit trees bloom too much, and the trees are full of flowers, so the yield is low. However, when the flower amount is only moderate and uniform, the fruit setting rate is high and there are many fruits.

Because of this "tree full of flowers", the nutrient branches, leaves, buds and flowers on the spring shoots are competing for nutrition. Due to insufficient nutrition, leaves are few and small, and buds and flowers are also small and deformed. Finally, due to insufficient nutrition, the flowers and fruits dropped seriously and the fruit setting rate was low. Finally, only half of the trees were left.

But in the "semi-tree flower", the nutrients stored in the tree can fully supply the growth of flower organs, and the quality of flowers is better. In addition, the branches and leaves are rich in nutrients, which can produce enough organic nutrients for the growth and development of young fruits after flowering, with high fruit setting rate, normal fruit growth and development, less flower drop and good fruit hanging.

It can be seen that strengthening orchard management, strengthening tree vigor and improving tree nutrition level are the keys to reduce flower and fruit drop, and at the same time, various effective measures should be taken according to the specific situation of flower and fruit drop.

0 1

Strengthen on-site management

Strengthening field management is the basic way to improve the nutritional level of trees. The nutrients needed by deciduous fruit trees at flowering stage are mainly storage nutrients. Therefore, we should first pay attention to measures such as topdressing, irrigation and pest control after last year's harvest to improve photosynthetic efficiency, accumulate storage nutrients and improve flower bud quality.

Secondly, strengthen spring management, topdressing, irrigation and intertillage as soon as possible, spray foliar fertilizer on branches before flowering, replenish nutrients consumed by a large number of flowers at flowering stage in advance, assist in thinning flowers and picking fruits, adjust the nutrient distribution of trees, ensure the demand for nutrients for flowering and fruit setting, and improve the fruit setting rate.

02

Create good pollination conditions

For cross-pollinated varieties, pollination trees should be rationally allocated, and on this basis, the following auxiliary measures can be taken.

(1) Most fruit trees are insect-borne flowers. Increasing the bee colony in the orchard at flowering stage can obviously improve the fruit setting rate. The orchard should put beehives before flowering, and the best time to put bees is after 20% of the flowers in the whole garden are open. Because bees have the habit of flying forward, beehives should be placed in every row or several rows. The beehive spacing is generally100 ~150m. Don't spray pesticides during flowering to prevent bees from being poisoned and dying.

(2) When pollinated varieties are scarce, pollinated varieties with flower buds can be grafted on perennial branches of crown to improve pollination rate. If the tree is still small, according to the principle of configuring pollinated trees, some plants in a single variety orchard can be grafted onto the whole tree and replaced with pollinated varieties.

(3) Orchards lacking hanging pots and flower branches can cut off the flower branches of pollinated varieties at the beginning of flowering, insert them in water tanks or jars, and hang them on trees that need pollination. In order to improve the pollination effect, we can tie the cut flower branches to a long stem when hanging the pot, extend it to the upper part of the crown, gently shake the long stem and knock off the pollen for pollination.

03

artificial insemination

Artificial pollination should be carried out when pollination varieties are lacking or the climatic conditions at flowering stage are not good. Artificial pollination must grasp the opportunity. According to research, pollination on the opening day of each flower is often the most beneficial to fertilization and fruit setting. Therefore, according to the phenology over the years and the temperature and humidity changes in the spring of that year, the flowering period of that year is predicted in advance, and pollen is prepared in advance to ensure timely pollination.

Artificial pollination should be carried out at 6: 00 ~ 10: 00 on a sunny and windless morning. Apple trees should have central flowers, with only 3-4 flowers per inflorescence. In order to save the amount of pollen, according to the germination rate of pollen, the pollen can be diluted by 5~ 10 times (adding talcum powder or starch) and planted on the stigma artificially. During liquid pollination, pollen can be mixed into a sugar solution with a concentration of 5%, and 10 ~ 12g pollen, 0.3% urea and 0. 1% grain boron can be added into every 5kg sugar solution. Pollination solutions should be used together and should not be shelved.

04

Application of growth regulator

The direct cause of falling flowers and fruits is the abscission layer at the base of flower stalk, and the formation of abscission layer is related to the deficiency of endogenous hormones (gibberellin, auxin, etc.). Therefore, spraying natural growth regulators with proper concentration and adding a small amount of boron during or after flowering can increase the content of these substances in young fruits, thus preventing the stalk from falling off and improving the fruit setting rate.

05

blossom and fruit thinning

Excessive flowering and fruit setting consumes the storage nutrition of the tree, reduces the leaf-fruit ratio, reduces the manufacturing state and accumulation level of the tree nutrition, and affects the growth of the next year. Cherish the extra flowers and fruits and improve the nutritional level of trees, which is not only beneficial to the growth of branches and roots, but also can enhance the disease resistance of trees. Thinning flowers and fruits can save invalid consumption of nutrients, reduce natural thinning of young fruits due to nutrient competition, reduce invalid flowers, increase the proportion of effective flowers, and thus improve the fruit setting rate.

06

Other ways

Pruning in summer, pest control, improving soil permeability and increasing tree nutrients can also improve fruit setting rate.