In article the biological characteristic of a weed – a sow-thistle pink is given. The fast and wide circulation of a weed is noted. Agrotechnical and chemical methods of fight against it are given.
In the course of evolution and long fight for existence in weed plants such biological features which at cultural plants are developed in manshy degree developed: high reproducibility, change are adapted for territorial distribution, have the stretched period of germination and very a progressive tense keep the vsxozhest in the soil, ability along with seed, vegetativno to breed root young growth, the root offsprings, strongly developed deep into and on the horizons root system Therefore the great value in receiving the greatest possible crop, is given to fight against them. At meeting gerbologov Ukraine the corresponding member of UAAN O. Ivaschenko declared that as a result of a contamination of a yield loss of cultures of continuous sowing can make from 20 to 50 %, and shirokoryadny – more than 50 %.
The special attention from weeds is deserved by a sow-thistle pink, recently everywhere extended on all territory both Old, and the New World. It is the korneotpryskovy, exclusively malicious and trudnoiskorenimy weed which is working great mischief to agricultural industry. In Ukraine meets everywhere, litters all field and garden cultural plants, gardens, vineyards, grows on the raw lands (fresh deposits), "loves" an irrigation . Got this weed and landowners of our peninsula. On our fields it was possible to see pictures of a sow-thistle pink various size, but it were nevertheless curtains, and now in each area of the republic wide fields of this "culture" thus blossoming.
In the experiences which have been carried out by I.Shevelev, it was established that roots of a sow-thistle pink in the first year of the life reach depth of 3,5 m, for the second year – 5,75 m, and on the third – 7,2 m. Such root system, strongly dries up and exhausts the soil, strongly oppresses cultural plants. According to the data received by Norwegian
scientist E.Korsmo, from one hectare of the ground area the sow-thistle takes 138 kg of nitrogen, 31 kg of phosphorus and 117 kg of potassium. Winter wheat, at a grain yield of 20 c/hectares, takes from the same area of 90 kg of nitrogen, 30 kg of phosphorus, 60 kg of potassium. Having carried out simple calculations, it is possible to tell that the sow-thistle takes such amount of nutrients which would suffice for receiving 32 c of grain of wheat from the soil.
At the same time this weed strongly shades grown-up cultural plants. F.Cheskis’s researches showed that the weight of plants which grew on sow-thistle curtains, decreased: at sunflower for 94 %, at corn for 82 %, in comparison with weight grown on the free areas from a sow-thistle.
Botanical characteristic and some biological features. A sow-thistle pink - a perennial, dvudomny korneotpryskovy plant of family slozhnotsvetny. A stalk high – 45-70 cm, direct branchy with prickly wings.
It consists of elevated and underground parts. The underground part of a stalk in length from 15 to 25 cm settles down in an arable layer of earth, has small colourless leaflets and mochkovaty roots. Leaves vyemchaty, oblong, on prickle tips to 5-6 mm. Flowers krasnofioletovy or pink, are collected in top baskets. A fruit – the extended semyanka with a short meeting that creates favorable conditions for distribution of seeds by a wind.
The sow-thistle pink as vegetativno, and seeds breeds. Seed promotes a fast and wide circulation of the miner. By scientists of the Poltava experimental station it was established that from 10-12 sow-thistle stalks in a curtain on 1 square meter it is possible to litter with seeds more than 10 hectares of the ground area.
The young plants which have grown from seeds, form in the beginning a vertical root from which in different directions and on different depth horizontal lateral roots of the first order depart. At some distance these roots utolshhayutsya, do a bend and go deep steeply into depth, and on a place of a bend kidneys and escapes from which elevated stalks of a sow-thistle grow are formed. So the sow-thistle expands extensively and creates curtains. Under optimum conditions of development it forms dense the steblesty. Its curtains from 4 to 28 m in diameter are closed both for cultural, and for segetalny plants.
But nevertheless the leading role in reproduction of a sow-thistle belongs to a vegetative way. The basic and its most dangerous source on the lands which to some extent have been already littered with it, are bodies of vegetative reproduction – roots and root shoots. Their reproductive ability at podrezke is extraordinary great. It is noticed that pieces in length of 10 mm and diameter of 1 mm grow even. Than it is less than a length of a piece, subjects from smaller depth grows and, on the contrary, root pieces in length of 25 cm are capable to sprout even from depth of 50 cm, and got accustomed in the spring (April-May) by the end of summer fructifying stalks already give. Their high prizhivayemost speaks that vegetiruyushchy plants accumulate in roots a significant amount of nutrients – polysaccharides which structure includes inulin thanks to which root pieces and possess such high ability to growth. Except a stock of nutrients, their prizhivayemost is influenced by humidity and soil temperature. Therefore plowing in the early spring and late autumn not only doesn’t reduce quantity of plants of a sow-thistle pink, and on the contrary, leads to even bigger contamination of the soil and crops.
Complex measures of fight against a sow-thistle pink. The biological features of a sow-thistle considered above pink shows, how rather easily it is possible to destroy this weed while the plant is in a young condition and as it is difficult to eradicate when it already got stronger and bred. To get rid of it within a year or by means of one any reception it is almost impossible. Therefore it is necessary to apply long-term system of the agrotechnical and chemical receptions directed on exhaustion of root system to its destruction. Also it is impossible to allow it insemination as its seeds remain in the soil about 20 years and can give life to new plants under the developed favorable conditions.
Fight against a sow-thistle pink includes precautionary measures, agrotechnical and chemical.
Precautionary measures, this obstacle to distribution of its seeds with a sowing material of cultural plants, a timely podkashivaniye of weeds in all territories adjacent to arable fields.
By researches it is proved that there is a direct dependence between duration of the vegetative period of a sow-thistle and the saved-up mass of roots.
Therefore the best period for a skashivaniye – the beginning of flowering of a weed when in roots and rhizomes there is an intensive consumption of nutrients.
Agrotechnical measures. The axiom considered introduction and observance of crop rotations with scientifically reasonable alternation of the cultures having various biological features. In crop rotations conditions for control of a sow-thistle pink are created. The competition to it isn’t maintained practically by any of cultural plants, but nevertheless in crops grain (tritikale, a rye, a buckwheat, winter wheat) this weed tests considerable oppression.
Soil processing in a crop rotation under steam or previous culture is necessary for beginning at once after cleaning of the predecessor. For destruction of a sow-thistle pink carry out a postharvest lushcheniye of the soil a heavy disk harrow. It is one of the most effective receptions in system of processing of the soil. Optimum depth of a lushcheniye in droughty conditions 12-14 see. One pass of a heavy disk harrow provides cutting of plants of a sow-thistle for 25-30 % therefore it is necessary to apply a repeated lushcheniye. If humidity and soil density allows, sow-thistle cutting by cultivators-ploskorezami gives good results. At the damp soil it is possible to be limited to depth of a lushcheniye 8-10 see.
In process of sow-thistle growth (the height of sockets of 8-10 cm is admissible) carry out a repeated disking or plowing. Optimum depth of plowing 25-30 see. Plowing preferably early that roots and rhizomes of a sow-thistle dried on the sun. The best field for destruction of a sow-thistle considered pure steam: numerous cultivations during the spring-and-summer period promote considerable exhaustion of its root system.
Chemical control methods. For receiving bigger effect in fight against a sow-thistle pink it is necessary to unite agrotechnical methods with the chemical. To destroy a sow-thistle or at least suspend its growth only those chemical preparations which get into root system can.
In crops of grain grains of cultures, from among registered in Ukraine, the following herbicides are recommended: Lontrel 300, Cowboy, Cross-country, Bromotril, Dialen, Lendmaster , etc. They are applied in a phase of a kushcheniye of the grain. From the listed preparations the most effective Lontrel, an optimum dose of introduction on crops of winter wheat of 250 – 375 g/hectares is considered. In crops grain herbicide of Laren-of 8 g/hectares showed also high efficiency. All-destructive preparations on a basis glifosfata are better for using during the postharvest period: optimum dose of a preparation of 2-4 kg/hectares. Most often for destruction of a sow-thistle pink the group preparation glifosfatov – Raundap, is used by a dose of 3 l/hectares.
According to the Nikolaev experimental station, they received the greatest effect at Raundap’s introduction, a dose of 4 l/hectares; plants of a sow-thistle were in a phase of sockets in height 15-20 see. According to their data, in the south of Ukraine Raundap’s application till the end of September yields the best results. In later terms efficiency of a preparation decreased.
It is also noticed that at application of herbicides together with superficial active substances, the Trend type, efficiency of herbicides increases that gives the chance to reduce a preparation dose by 10-15 %.
On extra arable lands herbicide is applied to fight against a sow-thistle the Arsenal, by norm of 2-3 l/hectares, providing weed destruction for 90-95 %.
From experience of fight against a sow-thistle pink in stationary experience of the Crimean institute APP. In the experience put on fields of institute in 1975, separate elements of system of agriculture where ways of processing of the soil entered were studied; on their background norms of a food of plants and ways of fight against weeds were studied.
In the first rotation of a devyatipolny crop rotation quantity of weeds including a sow-thistle pink, it was minimized. Alternation of cultures in a crop rotation the following: black steam, winter wheat, winter barley, corn on a green forage, the winter wheat, the occupied steam, winter wheat, summer barley, sunflower. Such crop rotation where the grain occupy 55,6 %, couples of 22,2 %, and sunflower of 11,1 %, on structure of cultivated areas is considered the best for fight against weed vegetation. Fight against it consisted in strict observance of all agroreceptions directed on its mechanical destruction. In crops of grain grains and corn agrotechnical receptions were supplemented with introduction of herbicides of group 2,4 D, on sunflower crops – Treflan’s soil herbicide and his analogs.
In the second rotation of a crop rotation herbicides applied only in crops winter grain and only at excess of a threshold of injuriousness of weeds. In crops of summer barley and in occupied to pair herbicides weren’t applied in crops propashny too applied only agrotechnical measures of fight.
The quantity of weeds in the second rotation decreased seven times, in comparison with the first. Allotments with curtains of a sow-thistle pink were on the strict account from the moment of a laying of experience. The quantity them was minimized, and the sizes of 1,5-2 m in diameter were observed generally on fields propashny.
In the last rotation of a crop rotation (1996-2005) the quantity of annual weeds remained at one level with the second rotation, and here sow-thistle existence increased for the simple reason a little: the field of a hospital is on a joint of three farms, at which lands in recent years mass reproduction of a sow-thistle pink was observed by a seed way.
It means that fight against this weed should be complex, including precautionary measures, agrotechnical and chemical. All actions are required to be carried out in due time and qualitatively. Distribution of this weed is possible and it is necessary to keep control.
To. ZHENCHENKO, Village TOMASHOV, research associates of the APP Crimean institute.