Biological features of table carrots. Biological features of table carrots. Which carrot leaves are simple

What is the importance of leaves in plant life? To answer this question, get acquainted with the structure of the leaf and the life processes that take place in it.

Compare the juicy, fleshy, spiky leaves of the agave with the wide, dense, leathery leaves of the ficus.

How different are the leaves of these indoor plants! Remember the tender, almost lacy carrot leaves and large leaves cabbage curled into a head. Even the leaves of the most common trees and shrubs are so different that it is difficult to confuse the leaves of birch and linden, maple and oak.

There are very large and very small leaves. Tropical flowers bloom annually in the Moscow Botanical Garden in summer. aquatic plant victoria-cruciana. Its leaves are so large that a three-year-old child sits on them, like on a raft, and the leaf floats freely on the water. And in the weed woodlice, the leaves are smaller than the nail. In some plants, the leaves have become tiny green scales or spines, as in cacti, camel thorn, and many other dry land plants.

externally leaves different plants very different from each other, but there is much in common between them.

In most plants, the leaves are green in color and consist ofleaf blade and petiole with which they are attached to the stem. Some plants do not have petioles. The leafless leaves are called sedentary. Such leaves are found in agave, flax, agave and many other plants. Leaves with petioles petiolate - are present in almost all of our trees: birch, oak, maple, linden, ash and many others. Sometimes at the base of the leaf petiole develop stipules.

According to the shape of the leaf blade, the leaves can be round, oval, lanceolate, linear, etc.

Distinguish between the leaves and the shape of the edge of their plate. For example, the edge of the plate may be serrated, like a birch. The edge of the leaf blade can be solid, like a lilac, and then the leaf is called whole-edge.

There are leaves with serrated, notched, crenate, wavy doubly-toothed and doubly-serrated edges. Consider the shape of the edge of the sheet in the figure.

Have you ever had to find unusual leaves consisting of only veins among last year's foliage darkened under the snow in the spring? The juicy soft green of the leaf blade rotted over the winter, and the more durable veins well preserved and visible.

The veins can also be seen on a living green leaf, especially when the leaf is held up to light. On the underside of the leaf blade, the veins are more visible than on top.

Water and substances dissolved in it move along the veins. The special fibers of the veins give the leaves strength and elasticity. Sieve tubes also lie in the veins, through which organic substances flow from the leaves to all organs of the plant.

In the leaves of some plants, the veins are parallel to one another. Such venation is called parallel. It is found in almost all monocotyledonous plants, such as wheat, rye, barley, corn, onions, and some others.

The leaves of the lily of the valley and the houseplant aspidistra, or "friendly family", havearcuate venation.Arc venation, as well as parallel, usually in monocotyledonous plants.

Dicotyledonous plants are more likely to have palmate or pinnate venation.

In the case of pinnate venation, a large main vein passes in the middle of the leaf, and smaller side veins depart from it, like in oak. At palmate venation of several main veins of the same thickness disperse to the sides of the base of the leaf blade, like a maple, nasturtium, cuffs and others. With palmate and in pinnate venation, the veins can branch repeatedly and, connecting with each other, howl thick mesh. If the main veins are weakly expressed, then the venation is called cirrus-reticulate or palmate-reticulate. Take a look on the leaves of maple, linden, apple or indoor plants such as geranium, lemon, begonia, primrose, rose. All these dicotyledonous plants have reticulate venation. By venation, it is easy to decide which plant is in front of you: monocot or dicot. But there are exceptions. For example, In a monocotyledonous plant, the crow's eye, the leaves have a net venation.

There are plants in which flowers develop singly at the ends of the shoots or in the axils. These are single flowers. And in other plants, flowers are collected in inflorescences.

Inflorescence It is a shoot of a plant that bears flowers and does not bear leaves.

inflorescences there are simple and complex. Inflorescences usually contain small flowers, which makes them highly visible to pollinating insects.

Cabbage, lily of the valley, bird cherry have inflorescence brush. In such an inflorescence, individual flowers are located one after another on well-marked pedicels extending from a long common axis.

simple spike form flowers without pedicels (that is, sessile) located on a common axis of the inflorescence, like in plantain. Inflorescences of wheat, rye, barley are called complex ear. In this inflorescence, several spikelets sit on a common axis, each of which is formed by several flowers (in rye, for example, two).

cob differs from the spike in the thick, usually fleshy axis of the inflorescence.

simple umbrella- an inflorescence in which the pedicels emerge from the top of the axis of the inflorescence. Primrose has such an inflorescence,.

The inflorescence is a simple umbel. Example -

Simple inflorescences can be grouped into compound inflorescences. Carrots and parsley have inflorescences-umbrellas, consisting of several simple umbrellas. Such an inflorescence is called complicated umbrella.

And I would like to begin this chapter with a quote from Ursula de Guin's book "The Wizard of Earthsea":

Tell me, what is that plant beside the path?
- Immortal.
- What about that?
- I do not know.
- It's called a quatrefoil. Ogion stopped and pointed the brass-bound tip of his staff at a nondescript weed. Ged examined it carefully, took up the withered pod, and seeing that Ogion was not going to say anything more, he asked:
"What use is it, Master?"
- None, as far as I know.
They went on, and Ged soon threw away the pod.
- When you recognize the quatrefoil in all seasons by root, by leaf and by flower, by sight, by smell and by seed, only then will you be able to learn to pronounce its real name. And this is more than knowing what benefits it brings.

At one time I was lucky, and one professor of Botany taught me to understand how important it is to be able to distinguish herbs by appearance. All of you took Botany lessons in ordinary schools and taught that plants are divided into classes - dicotyledons and monocots, which in turn are divided into families, and families - into genera. We will not delve into botany. I will try to remind you only what will help you determine what kind of plant is in front of you.

What characteristics are striking in the first place?

Naturally, you need to start with what is in front of you: plants with woody stems (trees, shrubs, woody vines) or herbs, that is, plants with non-woody stems.
Let me remind you that:
Trees are usually large plants with perennial woody stems. Every tree has a trunk and branches. Tree branches form their crowns (oak, linden, poplar, aspen, birch, and so on).
The shrub can grow like a small tree, but its trunk begins almost at the very surface of the soil and is difficult to recognize among the branches. Therefore, shrubs do not have one trunk, like trees, but several stems extending from a common base (elder, hazel, lilac).
Herbs are plants with non-woody stems. Usually they always have green and juicy stems. The size of herbs can be very different - from microscopic (duckweed reaches only a few millimeters) to very large (banana, which is a grass, can reach 7 meters, and hogweed easily grows taller than human height.)
Both trees and shrubs are perennials. The lifespan of some trees, such as oaks, can reach thousands of years.
Herbs can be annual (born from a seed, go through a full cycle in a year and, after the formation of fruits with seeds, die; these are violet, radish, wheat), biennial (roots, stems and leaves develop in the first year, plants bloom in the second year, bear fruit and die; these are beets, radish, cabbage) and perennial (roots and other underground organs with buds live long enough, the ground part of the plant goes through a cycle every year, growing in spring and dying off in autumn; these are nettle, dandelion, coltsfoot) .

After determining what exactly is in front of us, grass or tree, let's move on to the study of the sheet.

The leaf is part of the escape. Outwardly, the leaves of different plants vary greatly, but there is much in common between them. The leaves of most plants are green in color and consist of a leaf blade and petiole, by which they are connected to the stem.

It will not be superfluous to recall the veins - the blood vessels of the plant. The forms of venation differ in appearance. You will immediately understand what kind of venation a leaf has, as soon as you see it. It is parallel, arc and mesh.
Parallel venation occurs in monocotyledonous plants, for example, cereals. Such venation will be found in sedge or wheat, in some types of palm trees and in daffodils. Arc venation can be found in plantain or lily of the valley. Well, reticulate venation is very characteristic of the leaves of trees, however, as well as for all dicotyledons.

The leaves can be needle-shaped (coniferous), scaly (Petrov's cross) or another form - simple or complex.
If there is one leaf blade on the petiole (linden, maple), the leaf is called simple. A leaf consisting of several leaf blades connected to a common petiole by small petioles is called complex (strawberry, chestnut, acacia). In such leaves, each plate usually falls off independently of the others. Simple and compound leaves, in turn, are also divided into groups:

simple leaves:

Palmately dissected (meadow geranium)
Palmate (maple)
Palmate-lobed (cuff)
Pinnately-lobed (oak)
Pinnately dissected (marigolds)
Pinnate (meadowsweet)

compound leaves:

Trifoliate (strawberry)
Palmate (chestnut)
Paired pinnate (rowan, ash)
Unpaired pinnate (acacia)
Doubly compound (mimosa)

In herbaceous plants, attention should also be paid to the root. The root system is divided into two parts - taproot and fibrous. Even by the name it is already easy to understand how to distinguish them.
The easiest to understand is carrots. This is a prime example of a tap root. And those mini-roots that extend from the main root (the carrot itself) are called lateral. If you carefully dig up a dandelion, you will see it has a main pronounced root in the form of a rod and a bunch of small lateral roots on it. This is also a typical example of a rod system.
Sometimes additional roots depart from the stems and leaves, rather weak compared to the main one. They are called adjuncts. For biennials and perennials in the second year of life, the main root dies off, and the plant lives off adventitious ones.
Now let's pull the wheat out of the soil and study its root. The main root is not visible .. all the roots come from the stem, and they are approximately equal to each other. Each has additional small side roots. This is a typical representative of a plant with a fibrous root system.

flowers:

On the net you can find several determinants that suggest starting the definition of a flower with a color. But here you should pay attention to the fact that sometimes the color differs from the generally accepted one. For example, if a plant normally blooms with pink and red flowers, individuals with white flowers may also occur, and plants with blue or blue flowers sometimes have pink and whitish flowers.

Correct (chamomile)
Incorrect (mouse peas)
Divided (onion, tulip)
Two-lipped (sage)
Joint-leaved and joint-petal (asparagus)
Calyx with subcup (mallow)

Inflorescences:

Inflorescences are groups of flowers located close to each other in a certain order. They can be simple or complex. Usually small flowers are collected in inflorescences, since insects are more likely to notice a large combined flower than a small single one.
Depending on the type of branching, the length and location of the axes of the inflorescence and the sequence of initiation of flowers, many inflorescences are distinguished, for example:

Brush - the main axis has an indefinitely long growth, and flowers are laid on it, approximately equal in length to the pedicel (double-leaved manikin).
Umbrella - the internodes of the main axis are shortened so that all the pedicels come out as if from one point (a simple umbrella is a cherry, a complex one is a carrot).
The cob differs from the spike in the thick, usually fleshy axis of the inflorescence (calamus).
Head - the main axis is shortened and somewhat expanded, flowers are sessile or on short pedicels, collected in a compact inflorescence (clover).
A simple spike - they form flowers that do not have pedicels (that is, sessile), located on a common axis of the inflorescence, like a plantain. Inflorescences of wheat, rye, barley are called a complex ear. In this inflorescence, several spikelets sit on a common axis, each of which is formed by several flowers.
Basket - the main axis is saucer-shaped expanded and sessile flowers are located on it, opening from the edges to the center; outside, the basket is surrounded by apical leaves pushed up to it, forming the so-called wrapper (umbrella hawk).
Dichasium is a complex inflorescence in which two branches (opposite or alternate) appear below the terminal flower on the main axis of the inflorescence, ending in flowers and sometimes also branching in turn (left). Dichasia is often called a semi-umbrella (buckthorn).
In nature, there are other types of complex inflorescences, which are a combination of inflorescences of the same or different types. Examples of complex inflorescences, in addition to dichasia, are: a complex umbrella (left), a complex spike, panicle, head from baskets (right).

Carrot is a biennial plant. This means that in the first year a rosette of leaves and a storage organ are formed - a thickened fleshy root (root crop). In the second year, stems, inflorescences, flowers, fruits and seeds are formed, after which the plant dies. The most valuable part of the plant is the root.

The root system of carrots is pivotal, penetrating deep into the soil. The shape of root crops can be round, oval, truncated-conical, conical and cylindrical. The size of the root crop is short (less than 10 cm), medium (11-15 cm), long (more than 15 cm). In Russia, the length of the root crop rarely exceeds 30-40 cm, but it is known that carrots are grown in Mexico, the root crops of which reach 2 meters.

By diameter, root crops are divided into thin (less than 2.5 cm), medium (2.6-4 cm), thick (more than 4 cm). At optimal conditions growing, depending on the varietal characteristics, their mass grows small (less than 80 g), medium (80-150 g) or large (more than 150 g). In areas with loose fertile soil, the mass of root crops can be 300-500 g or more.

The color of the surface of the root in the most common varieties is orange, red-orange, red, pink-orange, and in rare varieties - white, light green, yellow, purple. The surface of root crops is smooth, uneven, bumpy. Small or deep eyes are clearly visible on it.

The root crop is fleshy, its woody part (core) is coarser and less sugary than the cow ( upper layer). The latter is more brightly colored, and only in some varieties (for example, in Nantes 4) the core and bark have the same bright color. The shape of the core is clearly visible on the cross section of the root crop. It can be round, rounded-angular, faceted, star-shaped. The size of the core is considered small if it is less than 30% of the root diameter, medium - 30-50% and large - more than 50%.

Rosette leaves of carrots are simple, pinnately dissected, with petioles. The contour of the plate is rhombic or triangular. The shape of the rosette of carrot leaves can be semi-erect, sprawling or pressed. Leaf petioles are long, thin, grooved, glabrous or pubescent, light green, glaucous, sometimes with anthocyanin pigmentation. The color of the plate is green, in Asian forms it is dark green, often gray-green.

Carrot flowering is observed in the second year of the plant's life. The height of the stems by the beginning of flowering reaches 1 m. The stems are fistulate, ribbed, bare or pubescent, branched, green or yellow-green. Each stem bears an inflorescence - a complex umbrella, consisting of individual small umbrellas.

In most plants, the flowers are small, bisexual, but male-sterile forms are often found.

Carrots are one of those vegetables without which it is impossible to cook some dishes. In addition to excellent taste and the possibility of long-term storage, carrots contain many important vitamins for humans, so everyone who has their own plot grows it. But sometimes it is not possible to grow a crop of this type of root crop: the tops on it turn yellow, curl, and rather small fruits grow instead of large carrots. In the article we will tell you why carrot leaves turn yellow / dry / curl / fall off / turn brown, how to deal with the problem.

Why can carrot leaves dry

What to do if the tops on the carrot began to turn yellow? First of all, find out the reason. To do this, it is necessary to carefully examine the plants, dig out several diseased specimens from the ground and then proceed to treatment, having previously removed all the affected plants.

Yellowed leaves on carrots appear quite often and can be the result of various kinds of pests and diseases, so you need to deal with such a nuisance as soon as possible.

Employees of economic enterprises, scientists and experienced gardeners noted that sometimes gardeners and summer residents themselves are to blame for this, choosing seed without taking into account the climatic characteristics of their region or, for example, sowing carrots before winter early varieties. In addition, it is necessary to properly prepare a bed for carrots, take care of the plant in compliance with the agricultural technology of this crop. But if all this is done correctly, and the harvest leaves much to be desired, then what was done wrong?

Fungi can also infect carrots. They are promoted by:

Crop rotation disruption.
Soil infected with pathogenic fungi.
Use of infected seed.
Excessive use of organic fertilizers.
Incorrect feeding.
Thickened shoots.
Extremely cold or extremely hot weather with high levels of humidity.

Possible diseases and ways to deal with them

Phomosis can affect carrots, this disease is dry rot, which does not appear immediately. At first, only the tips of the tops of the leaves wither and become gray-brown. The disease fully takes effect after the crop is harvested: specks appear on the top of the carrots. They gradually increase, spreading throughout the root crop. The rate of damage depends on the temperature in the storage: the warmer it is, the faster the crop will rot. Moreover, the spores of the fungus live for a very long time and can even destroy the next year's crop.

Measures to combat phomosis:

Cleaning the beds from the remains of plants after harvesting root crops.
The use of fertilizers with a phosphorus-potassium composition before sowing seeds.
Disinfect the storage before laying the crop with sulfur checkers.

No less dangerous is white rot. It is able to destroy not only the carrot crop, but also infect other plants that are grown on the site. In the garden, it may appear after using manure as a fertilizer. If carrots are sown thickly in the garden, weeds are not removed in time, the crop is not harvested for a long time, soil moisture will increase, due to which white rot spores actively multiply.

Oddly enough, but quite often the yellowed leaves of carrots appear simply due to improper care and insufficient watering, especially in the hot season.

You can notice the appearance of an unwanted guest by the fact that small yellow spots appear on the leaves of the tops. In addition, the tops will wither, curl. But the disease will fully manifest itself already during storage. harvested crop- softened spots will appear on the root crops, which will later be covered with a fluffy light coating. This is a mycelium of rot that spreads rapidly. Soon it will be covered with a crust with dark spots and droplets of moisture.

Measures to combat white rot:

Strengthen, but within the permitted limits, feed the plants with potassium.
Spray with preparations containing copper.
Disinfect storage.
Every 3-4 years, choose a different place for a bed for carrots.
Choose those varieties of this crop that are resistant to the disease.
Do not water the beds with cold water.

The edges on the lower leaves begin to turn yellow even when bacteriosis is affected. Then the yellowness spreads over the leaves, darkens, leaving only a yellow outline. Further, the infection affects the petioles, after which they begin to dry out. The stems are also affected: stripes and brown spots are noticeable on them. After that, root crops are affected, which can be seen from the appearance of small depressed spots of a brownish-brown color. It all ends with the fact that the carrot begins to emit an unpleasant odor, after which it is impossible to eat it or feed it to animals.

Bacteriosis control measures:

Before sowing seeds, they are kept for at least ten minutes in water, the temperature of which is +52 degrees.
3 weeks after germination, the seeds are sprayed with the Hom fungicide.
Be sure to disinfect the place where the crop will be stored in the winter. Read also the article: → "".

Alternatiosis belongs to those infectious diseases that can affect this crop at any stage of cultivation or storage. This disease is transmitted through infected soil or seeds. Its appearance can be understood by the change in color and shape of the leaves - they will begin to twist and darken. The yellow spots that appear on the tips spread very quickly, dry out, and the stems turn black. Petioles also wither, and then the root crop is also affected, neighboring plants are infected. This happens very quickly and if you do nothing, it is unlikely that you will be able to grow at least a few copies of carrots - the crops will all die. You can save the crop by spraying the plantings with Rovral.

Unfortunately, yellowing leaves may appear due to various diseases, so you can never wait for the desired harvest or even lose the plant

Brown spotting can be seen even on the shoots of carrots. The disease is manifested by the appearance of dark brown dressings on the stems at soil level. Infected young plants die very quickly. If the infection occurred later, when the roots began to form, this will be noticeable by the fact that brown spots with a yellow border will appear on the leaf plates. The spots may be different shape and size. Later, black dots will appear on them - these are the fruiting bodies of pycnidia. They are the future wintering grounds for the pathogen. Affected leaves begin to curl, turn brown, dry out, fall to the ground, so they must be removed and burned after harvest.

In the fight against white spot, the following measures are considered effective:

Regular loosening of row spacing.
Treatment of the site with decoctions of horsetail, nettle, celandine.
Processing the garden with Immunocytophyte in June.
Liming the soil in the autumn of the previous season.

If spots of light brown color with a light center appear on carrot leaves, this is cercosporosis. So called fungal disease. Later, the spots will increase and brighten, and the edges of the leaves will twist. If the soil is moist in the area, a gray coating will appear on the spots on the bottom of the leaves. The spots will spread over the green part of the whole plant and then join. The greens will begin to turn black and rot. It will not work to wait for the harvest from carrots affected by cercosporosis, as the fruits will be shriveled and small.

Tip #1 To prevent infection of the site, it is necessary to warm the seeds in water at a temperature of 50-52 degrees. If an infection has occurred, experts recommend spraying carrot beds with a Bordeaux mixture. To do this, prepare a one percent solution.

Types of pests of carrots and measures to combat them

Not only fungal or infectious diseases can affect carrot plantings, but also pests. In order to prevent the complete death of the crop, it is necessary to start fighting them immediately after finding at least one pest in your garden.

One of the dangerous enemies of root crops, experts call the carrot fly. The pupae of the fly overwinter in the soil. In April, a younger generation emerges from them. The fact that the carrot fly struck the shoots that appeared can be understood by the fact that the tops, instead of green, begin to acquire a bronze color. After a week or two, the affected plants begin to dry out and then die. If you do not remove infected plants, the insect will lay eggs in the soil. The hatched larvae will spoil the roots, after which they will become bitter and no longer suitable for food.

In order not to form yellow spots on the leaves of carrots, many gardeners and gardeners recommend constantly fertilizing the soil, feeding plants, and also paying special attention to care and watering.

You can protect yourself from flies by applying the following measures:

Plow the ground deep.
Weed the garden in a timely manner.
Treat crops with drugs such as Actellik, Arrivo and others.

Carrot psyllid is a very small insect. It usually lives on a pine tree, and if this type of tree grows nearby, there is a danger that the pest can fly over, or rather jump over to the garden to lay eggs on carrot tops. After a short time, larvae will appear that will feed on the juice of the plant, sucking it out of the leaves. Because of this, the tops turn yellow and dry out.

Tip #2 It is easy to get rid of leaf blotches. To do this, you need to insist on soap and tobacco waste and treat the crops with their solution.

To prevent this pest from appearing on the site, the following measures can be taken as a preventive measure:

Plant onions next to carrots.
Use fresh sawdust for mulching the garden.
Plant mustard seeds between carrot plants.

It is enough to appear on the site with just one bear, in a year the insects will multiply so much that the fight against them will be difficult. Therefore, it is not advisable to delay the destruction of the pest. To do this, you can use the Medvetoks bait or use one of the popular methods:

Dilute in a liter of water 50-60 gr washing powder. Lotus powder is most suitable for this purpose. Then you need to pour the mixture into the hole where the insect lives.
Pour a solution of vinegar with water into the well (a glass on a bucket).
Soak cotton wool in camphor oil and place it in the place where the pest lives.

Initially, the leaves may be green, but with various spots, specks, in which case it is already necessary to look for the root cause of such formations in order to prevent yellowing of the carrot leaves in advance

Among the most common pests is the naked slug. Moreover, both adult and young pests of this species are dangerous for carrot crops. They settle in places where the humidity is quite high. These are stones, fallen leaves, turf, soil. Slugs eat away tops and eat holes in root crops. The first sign of their appearance is whitish shiny paths.

To protect carrot crops from a naked slug, they must be treated with a salt solution (10% concentration) or superphosphate. The following measures will be no less effective:

Deep digging of the soil.
Introduction of ammonium nitrate.
Disinfection before work of all garden and garden tools.
Planting black elderberry next to the garden (slugs really dislike it).

A considerable danger to the carrot crop is represented by dark gray caterpillars - winter scoops. They damage root crops, gnawing them underground near the surface. Caterpillars feed not only on leaves, but also on fruits, making moves in them. This type pest is very prolific. Each female can lay over two thousand eggs per season. The use of drugs Politrin, Decis, Arrivo and others will help get rid of them.

According to most gardeners and gardeners, it is better to prevent the appearance of pests and diseases in advance, it is necessary to carefully care for the plant, and also feed it in time