Apple's physiological activities, biochemical reactions, and growth and development all depend on specific temperature conditions. Without the right thermal environment, their normal growth can be hindered, damaged, or even lead to death. Temperature plays a critical role in regulating apple's life processes, influencing everything from metabolism to fruit quality.
The impact of temperature on apple growth is primarily reflected in several key areas:
1) **Three-Point Temperatures**
Each stage of apple growth requires specific temperature ranges—minimum, optimal, and maximum. The minimum temperature for most apple varieties is around 5°C, with an optimal range of 13–25°C and a maximum threshold of about 40°C. These values vary depending on the variety, plant part, age, growth stage, and environmental factors. Different species also have varying optimal average temperatures during the growing season.
2) **Accumulated Temperature**
Apples require a certain amount of accumulated heat throughout their growth cycle. This factor significantly affects growth, development, yield, and fruit quality. Accumulated temperature is widely used as an indicator for variety characteristics, phenological forecasting, and ecological zoning.
3) **Effective Temperature Before Flowering**
Predicting flowering time often involves calculating effective accumulated temperature above 5°C. On average, apples need 160–180°C above 5°C before the first bloom, though this can vary between years and regions. The length of the flowering period also depends on temperature: at 7–8°C, it may last 50 days, while at 12–13°C, it shortens to about 30 days. Variability in accumulated temperature highlights the importance of local climate conditions.
4) **Flowering Temperature**
For successful flowering, apples must accumulate enough heat. Optimal flowering temperatures are around 11.4–11.8°C, with pollination best occurring between 17–18°C. Bees, which play a crucial role in pollination, become active when temperatures rise above 10°C, making them more effective at 15–29°C. Pollen germination also depends on temperature, typically between 10–25°C, with optimal germination at 15–20°C. Above 30°C, pollen activity declines sharply.
5) **Spring Temperatures**
Apple trees are particularly sensitive to spring temperatures. Many apple-growing regions in China experience unstable spring weather, including late frosts that can damage buds, flowers, and young fruits. Cool temperatures after flowering affect fruit shape, with lower temperatures promoting elongated fruit shapes and higher temperatures leading to rounder, smaller fruit indices.
6) **Summer and Autumn Temperatures**
Summer and autumn are critical for flower bud differentiation, fruit maturation, and overall yield. Temperatures between 16.5–22.85°C are ideal for these processes. Excessive heat can reduce fruit quality, leading to poor coloring, soft texture, and lower nutritional content. For example, in Gansu Province, apples grown under summer temperatures of 16.2–22.7°C are known for high quality. Flower bud differentiation occurs best at 20–27°C, with many varieties starting this process after a stable period of temperatures above 20°C.
7) **Winter Chilling Requirements**
Apple dormancy is primarily induced by low temperatures, not by day length or dryness. The chilling requirement is measured in "chill hours"—hours below 7.2°C. Modern apple varieties cultivated in warmer regions require fewer chill hours than traditional ones, ranging from 500–1700°C compared to earlier needs of 1400–3684°C. This shift reflects the adaptation of apple cultivation to changing climatic conditions.
Glucoside Powder also known as glycosides or glycosides are cyclic acetal derivatives formed by dehydrating the semi-acetal hydroxyl group of a sugar or a sugar derivative (such as a glucuronic acid) with the hydroxyl group in another non-sugar substance by an acetal bond (ligand bond). Such as Spirulina Powder, Green Tea Extract Powder, Jujube Seed Extract Powder, and Rhodiola Rosea Extract, Ligands can be divided into the following categories:
According to the structure of the ligands, the structure of the ligands can be phenols, anthraquinones, flavonoids, and other compounds. For example, flavone and anthraquinone ligands, etc.
According to the solubility of the ligands: the ligands can be divided into water-soluble and fat-soluble ligands. Water-soluble ligands are usually soluble in polar solvents such as water and ethanol, while fat-soluble ligands are less soluble in water and more soluble in organic solvents.
According to the form of existence of the ligands, the ligands can be divided into primary and secondary ligands. Primary ligands are those that contain several sugar molecules originally existing in plants, while secondary ligands are those that produce fewer sugar molecules after hydrolysis of primary ligands.
According to the function of ligands: ligands can be divided into physiologically active ligands and inactive ligands. The ligands with physiological activity, such as saponins and flavonoid sides, have certain physiological functions in plants, such as anti-oxidation, anti-inflammation, anti-tumor, etc.
According to the structure of the ligands, the structure of the ligands can be phenols, anthraquinones, flavonoids, and other compounds. For example, flavone and anthraquinone ligands, etc.
According to the solubility of the ligands: the ligands can be divided into water-soluble and fat-soluble ligands. Water-soluble ligands are usually soluble in polar solvents such as water and ethanol, while fat-soluble ligands are less soluble in water and more soluble in organic solvents.
According to the form of existence of the ligands, the ligands can be divided into primary and secondary ligands. Primary ligands are those that contain several sugar molecules originally existing in plants, while secondary ligands are those that produce fewer sugar molecules after hydrolysis of primary ligands.
According to the function of ligands: ligands can be divided into physiologically active ligands and inactive ligands. The ligands with physiological activity, such as saponins and flavonoid sides, have certain physiological functions in plants, such as anti-oxidation, anti-inflammation, anti-tumor, etc.
Spirulina Powder,Green Tea Extract Powder,Jujube Seed Extract Powder,Rhodiola Rosea Extract
Shaanxi Changsheng Industrial Co., Ltd. , https://www.cncsbio.com