Fruit Swelling and Maturity

The length of this period varies depending on the tree species.

(1) Fruit expansion period:

It refers to the enlargement of the volume of pulp cells, and the enlargement multiples range from 30 to 300 times. Some tree species have only one swelling peak, while others have two swelling peaks, such as apples, the first in June / bottom to July / end, and the second in September to October. Then on the basis of a certain number of flesh cells in the early stage, the larger the volume expansion factor, the larger the future fruit size.

(2) Fruit maturity:

When the fruit reaches the natural size and shape of the variety, it enters the maturity stage, the contents gradually transform, the fruit surface is colored, the flavor increases, and the seeds change color until maturity, which mainly has the following physiological and biochemical transformation characteristics:

First, a large amount of starch is converted into sugar, and the sugar-acid ratio is increased;

Second, organic acids participate in respiration and are oxidatively decomposed or converted into insoluble substances, sour taste is reduced;

Third, under the action of pectinase, the original pectin is decomposed into soluble pectin, the flesh becomes crispy or soft, and the hardness is reduced;

Fourth, the various lipids and aldehydes accumulated in the fruit produce an aromatic odor under the action of various enzymes;

Fifth, wax and fruit powder are produced on the surface of the peel, which plays a protective and aesthetic role;

Sixth, ethylene is produced in the pulp cells, which promotes breathing and various biochemical processes and accelerates the maturation process;

Seventh, the color of the fruit surface with the decomposition of chlorophyll shows a background color of yellow, orange, and the like, and the pigment transported from the leaves further synthesizes anthocyanins to make the fruit surface show red and purple colors, called Complexion (color).

(3) Ction measures:

Ensuring sufficient supply of fertilizer and water, increasing the light and speed of leaves, applying growth regulators, and controlling diseases and insect pests.

Deciduous and dormant

(1) Deciduous period

Fallen leaves are a sign that the fruit tree is dormant

The normal deciduous temperature of temperate fruit trees begins when the average daily temperature drops below 15 ° C and the hours of sunshine are shorter than 12h.

Before falling leaves, a series of physiological changes are performed in the leaves, such as the decomposition of chlorophyll, light and effects and respiratory effects are weakened, nutrient flows into the branches, and finally the petioles form a layer and fall off. Various measures should be taken to protect the leaves Falling off too early or too late, if it is too early, it will affect the accumulation and production of photosynthetic products, which will further affect the wintering ability of the tree and the growth and development of spring in the coming year; As a result, some nutrients are lost before they are shipped to the branches. Therefore, pruning should not be performed at this stage, and base fertilizer should be applied in autumn.

(2) Dormant period

After falling, the fruit tree enters the dormant period. Although the external morphology does not change during this period, various physiological activities in the tree are still ongoing, such as breathing, transpiration, root absorption, synthesis, further differentiation of buds, and nutrient content in the tree. Transformation etc. (fruit tree below 9 ℃, peach below 15 ℃, pear 13 ℃)

Fruit tree dormancy can be divided into two stages: natural dormancy and forced dormancy.

Fruit trees cannot germinate and grow even if they are given suitable environmental conditions during natural dormant period, and natural dormancy requires a certain time and a certain degree of low temperature conditions, which is called cold demand. Generally expressed by the amount of low temperature required for buds, that is, the number of hours required below the average daily temperature of 7.2 ° C, such as 500-1200h for peaches and 900-1000h for apples and pears. By date, most fruit trees end naturally dormant after December to February.

Forced dormancy refers to the phenomenon of temporarily stopping growth due to unfavorable external environmental conditions (low temperature, drought, etc.). For example, in early spring, low temperature often causes fruit trees to enter forced dormancy through natural dormancy. Root dormancy is also forced The dormancy and production of facility ction is to artificially create suitable environmental conditions to break the forced dormancy and promote the fruit trees to enter the growing season in advance.

Zhengzhou Delong Chemical CO., Ltd. is the production base of plant growth regulators in China, which established in 2009, specializing in offering plant protection products. If you have any question, contact us any time.