Autumn is coming, why do some turn yellow and some turn red when the leaves wither?

Chlorophyll degradation and synthesis will cause leaf discoloration, and chlorophyll degradation will expose lutein and carotene, which is the main reason for leaf yellowing.

The decrease in chlorophyll content in plants leads to faster cell death, and the increase in oxygen consumption in intracellular mitochondria also leads to a slowdown in green photosynthesis, which makes plants show symptoms such as yellowing. The plants that are most prone to yellow leaves in autumn are mainly some flowering plants, such as gardenias, jasmine, etc. These flowers prefer to grow in a warm, moist and well-ventilated environment, and if the environment is not suitable, the leaves will turn yellow and wilt.

What are the things that need to be paid attention to when maintaining flowers and plants?

In autumn, the temperature is relatively low, and the growth of plants is relatively slow, and sometimes there is a phenomenon of no flowering. Flower friends should pay more attention to these phenomena in the maintenance of flowers and plants in autumn. This will ensure that it grows normally.

In general, the temperature drops relatively quickly in autumn, so it is normal for plants to have slight yellow leaves. But if the leaves are yellow, wilted, and unrefreshed, it is infected with fungal diseases. If the leaves are yellow, it is likely that the flowers and plants that have just been brought out of the summer have these problems.

Yellowing of leaves in autumn is actually a very normal natural phenomenon.

Chlorophyll degradation and synthesis cause discoloration of leaves.

Chlorophyll is the main pigment in plant leaves, which has many functions such as absorbing light, maintaining the oxygen balance in chlorophyll cells, promoting photosynthesis, and participating in important physiological activities of metabolism in the body. It can participate in photosynthesis and can promote the growth and development of plants. Chlorophyll is a special pigment that is first oxidized to oxygen during respiration, and then combines with organic compounds and undergoes redox reactions, which convert organic compounds into gaseous substances such as water and carbon dioxide.

When the amount of gaseous oxygen exceeds a certain limit, it causes chlorophyll to degrade and form chlorophyll a. When chlorophyll is degraded and synthesized, it can also cause discoloration of leaves.

Chlorophyll is generally found in the leaves, which give the leaves a green color before autumn arrives. In autumn, the plant will first ** some substances in the leaves, do a good job of stockpiling for winter, and after the chlorophyll is destroyed, the leaves show the background color when there is no green.

The chlorophyll is degraded, revealing lutein and carotene, which are the main causes of the yellowing of the leaves.

Synthetic anthocyanins. The frost leaves are red in February, and this is not a simple metaphor. Some frost leaves really have the same ingredients as flowers, that is, anthocyanins.

Anthocyanins are actually a protective pigment because too much sunlight can damage chloroplasts at low temperatures

Because in this season, some lutein and carotene in the leaves will undergo certain changes, so that the existing ones will turn yellow and some will turn red.

It turns out that plants do not excrete the waste products of their own metabolism like animals. They usually accumulate sediment in the leaves during the metabolic process, and at the same time return nutrients to the trunk or roots of the tree for future use, so the process of defoliation is the process of processing metabolites.

The newborn leaves are usually green, which is due to the chlorophyll. The new leaves mainly contain chlorophyll (green) and carotene (yellow), and the chlorophyll content is 8 times that of other pigments. In spring and summer, plants produce a large amount of chlorophyll for photosynthesis in order to grow, so the leaves are mostly green at this time.

The yellowing of the leaves is due to the decomposition of the various pigments in the leaves during the fall season. The nutrients from the leaves are redistributed to the trunk and roots for winter.

The yellowing of leaves in autumn is due to the decrease in temperature, dry air, fast evaporation of water, and insufficient light, which will affect the root absorption of plants and the progress of leaf photosynthesis.

The reason why the leaves turn yellow is because the temperature decreases in autumn and the light hours are shortened, which leads to a decrease in the chlorophyll content of the plant, and the pigment in the leaves changes, and lutein begins to work to cause the leaves to turn yellow. Leaves contain a variety of pigments, such as chlorophyll, lutein, carotene, etc. In autumn, the temperature drops, the air is dry, the water in the leaves evaporates quickly, and the light time is insufficient, which affects the absorption capacity of plant roots and the photosynthesis ability of leaves.

In summer, the chlorophyll content is higher than that of the other pigment, and the green color of the leaves will be darker. Some leaves also turn red, such as maple leaves and red leaves. The reasons why the maple leaves turn red are:

Maple leaves contain a large amount of anthocyanins, and with the change of seasons, anthocyanins will also change accordingly, so the performance of maple leaves is obvious when the seasons change. Some leaves do not change color throughout the year, but only lose their leaves, such as camphor trees, camellia trees, etc.

The main reason is that the enzymes corresponding to photosynthesis cannot play a catalytic role, and can only reflect the changes of the seasons in the form of fallen leaves.

The reason why the leaves turn yellow in autumn is that the roots and stems of the trees no longer deliver nutrients and water to the leaves in autumn.

The reason why the leaves turn yellow in autumn is that in autumn, the roots and stems of the trees no longer deliver nutrients and water to the leaves, and will break down the chlorophyll in the leaves, and transport nutrients to the roots of the tree as nutrients for the winter. The leaves also contain lutein, lutein, etc., and the leaves have no chlorophyll and nutrients, so only chlorophyll and lutein are left, so the leaves will show a yellow or red state.

Reasons for falling leaves in autumn

The fall of leaves is generally divided into two situations, one is that the leaves are already dead. Plants, like animals, are born, old, sick and die, and the other is a man-made "accident", such as a passerby picking off a leaf. Dead leaves have no physiological function and have to fall to dust.

The other is caused by the environment, and there are also two reasons for this: man-made and natural. In short, man-made is something man-made, such as a factory next to a tree or a nuclear power plant accident.

Leaves will choose to "actively fall in the face of adversity" to protect themselves. Natural environmental reasons are the most common situation, and the temperature drops sharply in autumn and winter, so it is impossible to carry out physiological activities, so it is necessary to hibernate people.

As the temperature drops, the stems have thickened bark, the roots are buried under the soil, and the thin leaves are left to fight alone. The impending cold also made these leaves, which were originally born for photosynthesis, at a loss. The wide leaf surface receives more sunlight, but it is less resistant to cold weather and is at risk of frostbite when the temperature is below zero.

The drop in temperature and the decrease in precipitation have directly made the process of not simply absorbing water "worse". There are many stomata on the leaves, and the tree loses a lot of water as it breathes. The leaves had no choice but to abandon them.

The reason why the leaves turn yellow in autumn is that the leaves are devoid of chlorophyll and nutrients, and only chlorophyll and lutein remain, so the leaves will appear yellow or red.

When autumn comes, the trees feel the change in climate from the autumn, so that their own large amount of chlorophyll covers the green chlorophyll, and people naturally see the leaves turn red or yellow. In autumn, deciduous trees stop growing and only need a small amount of nutrients to survive. Before the leaves fall, the trunk of the tree decomposes the chlorophyll, and the substances produced by the decomposition are transported from the leaves to the tree as nutrients for the winter.

When chlorophyll is decomposed, chlorophyllin is left in the leaves, so you can see the leaves turn from green to yellow. The leaves are green because of the chlorophyll in the leaves. However, in addition to green pigment, there are many pigments such as red pigment and yellow pigment in the leaves, but the amount is very small.

In autumn, the green pigment slowly fades, and the red pigment and yellow pigment are revealed.

All leaves contain green chlorophyll, which is used by trees to capture light energy and store it in the form of chemicals such as sugar. In addition to chlorophyll, many leaves contain other pigments such as yellow, orange and red.

Although these pigments do not photosynthesize like chlorophyll, some of them are able to transfer captured light energy to chlorophyll. In spring and summer, chlorophyll is much more abundant in the leaves than other pigments, so the leaves show the green color of chlorophyll, and the color of the other pigments is not visible.

Causes of leaf loss:

Defoliation is an adaptation of plants to unfavorable growth conditions in the natural environment, which can greatly reduce the transpiration of water, so that the plants can survive the cold of winter and the dryness of summer without dying. In fact, this is also a helpless move, in order to fight the ice and snow cold, I have to make a move to give up the car to protect the handsome.

In autumn, most of the leaves will dry out, turn yellow, and then wither and fall.

In autumn, the temperature drops and the light time is shortened, which affects the absorption capacity of the root system and the photosynthesis of leaves, so it cannot meet the growth and development of trees.

When the temperature drops and the air is dry, the water in the leaves evaporates quickly, but the ability of the roots to absorb water has been greatly reduced, and the water and nutrients are insufficient.

In order to survive the tree, the junction of the petiole and the leaf stem generates an isolation layer, the leaves are cut off from the water **, coupled with the low temperature, the chlorophyll is destroyed, and lutein and so on begin to be active, so the leaves will turn from green to yellow and fall off, with the autumn wind back to the embrace of the earth.

In fact, lutein, which turns leaves yellow, and chlorophyll, which turns leaves orange and red, are present in the leaves from the day they grow, but they are masked by the green chlorophyll.