The broomrape parasite belongs to the largest group of broomrape. This genus is distinguished by a large variety of species (known - 120, the most common - 40). Parasitizes on cultivated, weedy and wild plants. The most dangerous species are those that affect fodder, melons, vegetables, ornamental crops and sunflowers.
The broomrape parasite plant is classified as a consumer, as it feeds on prepared organic matter.
Main types
Within our country today, there are approximately 40 species of broomrape, of which five are parasitic on cultivated plants. The following types are considered the most harmful:
- sunflower;
- branched (hemp);
- Egyptian (melon);
- Mutel;
- alfalfa.
Description
All species of the broomrape parasite are perennial and completely devoid of chlorophyll. Due to their unusual way of life, they have some features: they differ in a peculiar appearance, do not have real roots. Instead, they have fleshy, short sucker fibers that stick to the roots of the host plant. The leaves of the plant are small, scaly, brownish, yellowish or lilac in color.
Stem
A broomrape parasite can have a brown, light yellow, blue, or pink stem. It is erect, fleshy, not branching or branching, height - about 45-60 cm. The base of the stem is club-shaped.
Flowers
The broomrape parasite plant has five-membered axillary flowers with a two-lipped german with 4 stamens. Color depends on the species and is whitish, blue or purple. The Germans are collected several dozen in a panicle spike-shaped or spike.
The plant is capable of self-pollination. Cross-pollination is carried out by a broomrape fly and bumblebees.
Seeds
The fruit is in the form of a box with two or three leaves. It contains more than two thousand seeds. They are very small, oblong or rounded, with a cellular surface. Color is dark brown, length is about 0.2-0.5 mm, width is about 0.16-0.25 mm.
The seeds are almost weightless, so it is very easily tolerated by the wind. They are also quickly spread by animals and birds, carried along with soil sticking to shoes and tools, wheels of walk-behind wheels, wheelbarrows, cars, etc.
Seeds in the ground can be stored up to 12 years in anticipation of the carrier. They germinate gradually. From the beginning of development to the formation of a flower, an average of 1.5-2 months passes.
Each species of a broomrape parasite plant differs in appearance, features of parasitic specialization, shoot structure and is adapted to parasitization in certain crops.
Sunflower Broomrape
This species is mainly harmful to sunflower. Of other plants, it can affect tomatoes, shag, tobacco, wormwood and others.
If there are a large number of peduncles of sunflower broomrape, the plant dies very quickly due to depletion and loss of water. Even if he manages to partially survive, the total yield will still decrease sharply. Broomrape not only takes away nutrients and water from the affected plants, but also poisons the seeds of the host with the products of its vital activity.
This species is distinguished by a non-branching stem, the height of which is up to 30 cm and even more. Bracts are sharp, ovoid, the corolla has a length of 12-20 mm. It is tubular, brown, strongly bent forward.
Egyptian (melon) broomrape
The plant harms potatoes, hemp, cabbage, tobacco, tomatoes, gourds, etc. The harm caused by this type of parasite is that it sticks to the roots of the host with nutritious organs and absorbs useful nutrients, depleting it and causing death.
The stalk of the plant is spreading, there are few ovoid-lanceolate scales up to 30 cm long. The corolla is tubular-funnel-shaped, 23-27 mm in length, significantly widened in the limb.
Branched (hemp) broomrape
This species infects many species of asteraceae, nightshade, cabbage, pumpkin, etc. It parasitizes mainly on hemp, tobacco, tomato, cabbage, carrots, melon, etc., consuming a large amount of nutrients and water. As a result, plant stems are not sufficiently developed, and cultures have an oppressed appearance. In addition, the yield of fibers in the affected plants greatly decreases and the strength decreases.
Branched broomrape is distinguished by a thin stem, in the middle part up to 4-5 mm, with rare scales, up to 25 cm long. At the base it is thickened, there are a large number of lateral shoots. The flowers are smaller than in the species described earlier. Their diameter is up to 15 mm. It looks like this broomrape parasite plant.
Petrov cross
This genus includes 5-7 species of plants that parasitize on the roots of shrubs and trees. Peter's cross reaches a height of up to 30 cm. The stems of the plant are covered with fleshy white scales, which are modified leaves.
The root system, attached by suction cups to the roots of trees, is able to stretch over a long distance and connect to other mother plants.
During the first years, the plant develops underground. After the rhizomes have developed, inflorescences will begin to appear.
Plants parasites of broomrape, Peters cross belong to the broomrape family.
Methods of struggle
When protecting against this parasite plant, a number of techniques are often used. The main methods of combating broomrape:
- Protection against dispersal of the seeds of this plant to regions and farms in which it does not occur.
- Thorough cleaning of broomrape seeds in infected areas.
- Systematic weeding and destruction of broomrape before seeds and inflorescences appear in order to prevent new infection of the soil. At the same time, the weathered plant is necessarily taken out of the site, after which it is burnt or buried deeply.
- The introduction of crop rotation, which exclude crops affected by the parasite.
Since broomrape can affect various wild plants, it is very important to fight it. For this, scientists and breeders offer several options.
First of all, crop rotation must be observed. Plant control methods are divided into two areas, namely, genetic and chemical control. With genetic control, such resistant hybrids as NK Neoma, Tristan, NK Alego are derived.
A promising area of ​​chemical control is germination stimulants. As you know, for germination of seeds of a parasite plant, root excretions of sunflower are necessary. That is why their analogues are synthesized, and after the necessary treatment, the broomrape seeds germinate and die immediately, since there is no host plant.
Clearfield (Clear Field) technology showed quite good results in pest control. For this, a special herbicide is used, which destroys all types of broomrape and weeds (including problematic sow thistle, ragweed, and grasshopper). Processed 4-7 leaves of sunflower hybrids, specially created for this technology. This herbicide is a water-soluble concentrate in which there are two active substances: imazapyr and imazamox. They are very quickly absorbed by the plant through the leaves and through the roots. Due to the active active substances, the formation of amino acids and protein synthesis is blocked, as a result of which the death of weeds occurs.
Also a fairly effective method of combating broomrape is provocative crops. In those places where there was a lot of broomrape in the previous year, sunflower is sown, which causes the mass growth of seeds of the parasitic plant. When a large number of peduncles appear or at the very beginning of the flowering of the weed, the crop is harvested for silage.
Another method of provocative broomrape control is the cultivation of corn. Unlike sunflower, it provokes the appearance of weed, but does not allow to develop and throw away seeds.
Rapeseed, flax, and rape are also provoked to germinate broomrape, but under these crops the parasite sprouts less than under corn.
The fight against sunflower broomrape
The fight against broomrape on sunflower is carried out as follows. The correct crop rotation is introduced, in which tobacco, sunflower and hemp are sown to their original place no earlier than after 6-8 years. As a result, the soil is cleaned of broomrape seeds. At this time, crops not affected by it are sown - sugar beets, soybeans, cereal breads, castor oil plants, onions, lallemantsigo, peppers. High-oil broomrape-tolerant species are planted from sunflower varieties.
Not bad from the seeds of the parasite cleans the soil provocative sowing.
Fight against cabbage broomrape
With cabbage broomrape, the control methods are as follows. Good results show early planting cabbage. As well as provocative crops.
On cabbage, broomrape parasitizes near the stem, so it can only be destroyed manually. Weeding in all crops before flowering is required. After harvesting tomatoes, tobacco, melons and cabbage, broomrape is collected and must be burned.
Particularly noteworthy are plant crops in which the roots stimulate germination, but they themselves are not affected by broomrape. For example, some varieties of clover and alfalfa.
Fighting Egyptian Broomrape
Since it is difficult to observe crop rotation for gourds, pure vapors are introduced, in the irrigation zone, “water vapors” that clean the soil from the seeds of the parasite plant well or transfer melons to new places. Autumn and winter watering also contribute to cleansing the soil from weed.