In article recommendations about increase of biochemical indicators of quality of grain of corn are made. It is noted that in the course of all vegetation of corn it is necessary to provide an optimum nitric food.
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Requirements to quality of corn grain will be various depending on its use. So, an indicator of quality of grain of the corn used in a forage by an animal of nedroblenny or in the form of compound feed, the quantity of fodder units per grain unit of mass serves. This size is defined as the content of proteins, carbohydrates and the fats which are a part of grain, and comprehensibility of these substances.
Corn grain as the raw materials for production of starch, should have its greatest number and, therefore, less protein and fat. It is very important thus that from crushed endosperma a corn zernovka starch easily was washed away. For quality of the starch the important role is played by its ability klejsterizovatsya and to give viscous paste – the structure of its molecule, in particular, a ratio amilozy and amilopektina matters.
All these indicators are interconnected and define fodder advantages of grain of this important zernofurazhny culture. Appearance of grain considerably characterizes its quality. After all grains of corn of various hybrids differ among themselves in a form, color and a chemical composition. But the general for them is their high caloric content so on power value grain of corn hasn’t equal. In one kg of grain soderzhitsya1,34 fodder units, while in oats kg – 1 k.e., summer barley – 1,2-1,21 k.e., winter wheat – 1,2 k.e. Besides Nutritional value of grain of corn quite high also is equal 338 kcal/100 of. Corn grain considerably surpasses all other grain crops in percentage of fats, except for oats. The content of vitamins B to corn also above, than in other zernofurazhny cultures. In grain of this culture the content of carotene makes 5,7 mg/kg, in oats – 1,9 mg/kg, and in summer barley only 1,2 mg/kg.
The wealth and a variety ximicheskogosostava grains of corn cause its high food value. Therefore eyozerno apply to feeding of animal all types. Perevarimost of corn grain the high: KRS and pigs digest it for 90 %. Besides the organic substance from corn grain is digested for 33 % better, than from oats. And caloric content of grain of corn is higher, than other grain. So, in 100 g of corn grain 330 kcal, wheaten–295, barley – 267 and sravnitelnomalov oat grain – 257 contain.
Certainly, corn – unsurpassed grain – fodder and silosnayakultura. The content of protein in grain depending on conditions of cultivation can vary in very wide limits, reaching the maximum value in droughty years – 13,5-14 %. Fodder value of grain of corn depends not only from the contents in the squirrel, but also from its aminokislotny structure is mute. Unfortunately, corn proteins are defective on irreplaceable amino acid – to a lysine. Owing to inferiority of corn forages on aminokislotny structure the efficiency of vegetable protein in animal husbandry is very low. Therefore, according to zootechnical norms of feeding, to corn sterns it is necessary to add on the average 30-50 g of a perevarimy protein on one to. unit.
It is counted up that if to feed agricultural animals balanced on protein and other nutrients with sterns, for production of their meat it would be required twice less that would give the chance to save a half of used fodder grain. Zein containing in protein of corn, is acquired badly and consequently treats defective squirrels. Among all fractions of protein it contains the smallest quantity critical for grain of corn of amino acids – a lysine, methionine and triptofana. Because of the low maintenance of a lysine in sterns over 10-11 kg of vegetable protein now are spent for production of 1 kg of animal protein instead of 5-6 kg. It is necessary to emphasize also that the need of agricultural animals for amino acids more, than for 90 % is provided by proteins of a phytogenesis. It small efficiency of animals which fatten only corn grain without addition of high-grade albuminous forages speaks. Here put here in what. Protein of whom fabrics of an animal organism consist, is synthesized only from vegetable protein. The lysine regulates this process. From total of the albumens concentrated in grain of corn, on synthesis of animal protein 5-6 %, other part – a power material are used only. The insufficient amount of protein in a corn forage leads to its overexpenditure on creation of unit of cattle-breeding production and causes increase of its prime cost. If the aminokislotny composition of corn protein was balanced on a lysine, on synthesis of animal protein all would be used the grain corn. But actually it doesn’t occur, because the content in grain of the above-named organic substance remains rather low. Nowadays in our country there is no more powerful limiter of rates of increase in production of live stock products, than an albuminous underfeeding. After all protein – one of the most valuable nutrients of the forages influencing an organism of animals. Not casually Dutch scientist Nulder (1935) called it a protein that in transfer with Greek means main, i.e. the main.
The economic essence of a problem of forages and fodder protein consists that they in structure of expenses for production of milk make 40-60 %, on production of meat – 65-70 %, pork of-40-60 %, broilers – 70-75 %, eggs – 50-65 %. Unfortunately, in Ukraine many years the considerable deficiency of a fodder protein which is annually making 1,5 million t is observed. In this regard efficiency of animals and a bird low because of what 33 % of production don’t reach, in 1,5 times increases an expense of forages on production of milk, meat, eggs, wool, and prime cost of this production the high. With increase in the content of protein its nutritional (fodder) value increases in grain of corn, though biological value of the protein decreases a little. Due to the annual increase of requirement for the balanced sterns receiving high-albuminous hybrids of corn has big practical value.
The experiences which have been carried out at Institute of a grain farm of UAAN, it was established that increase of the content of protein generally occurs at the expense of invaluable in the fodder relation of zeinovy fraction. In this case share reduction not zeinovy proteins in grain reduces its quality a little. According to IZH UAAN in the Ukrainian steppe one fodder unit of corn the insignificant quantity of a perevarimy protein is necessary. So, when harvesting this culture in a phase of dairy ripeness of grain the maintenance of a protein makes 75 g in 1 to. e., in dairy and wax ripeness – 65 g, and in full ripeness only – 53 g. The content of protein in grain – a changeable sign which, depending on cultivation conditions, can vary in very wide limits – from 7 to 14 %, reaching the maximum value in droughty years of 13,5-14 %. It kolichestvov the present steadily decreases that is natural, reduces its fodder advantages.
It speaks, first of all, the strengthened selection of this culture on high productivity indifferently to quality of grain, and also an intensive use of an arable land without introduction of enough of fertilizers. Decrease in the content in grain of the crude protein, observed now, it is also possible to explain the following reasons:
Ø development of erosive processes;
Ø unproductive losses of nitrogen;
Ø reduction of volumes of introduction of nitric fertilizers;
Ø introduction of the new hybrids providing more big crops, being accompanied formation of zernovka of the large sizes;
Ø vypakhannost of soils etc.
In scientific literature the fact of decrease in the content in protein grain at increase in the sizes of zernovka and growth of productivity gained the name effect of diluting. According to this "effect", as a result of increase of productivity of grain of hybrids of corn, there is a decrease in the contents in it a crude protein. Carried-out supervision showed that usually at poor harvests grain is formed small, and at the high – large. In a fine grain the amount of protein is always higher, than in the large. This results from the fact that in endosperme protein is distributed non-uniformly: its contents is higher in the peripheral part adjoining an aleyronovy layer, and to the center endosperma it decreases. Existing inverse relationship between size of a grain yield of corn and the contents in the squirrel is mute was is noted in works of many authors. Investigating at genetic level existing interrelation between size of a crop and the contents in the squirrel is mute, existence of inverse relationship was noted. But it at all doesn’t mean that selection has no prospects in increase of the content of protein in grain and the removal of hybrids of corn which is at the same time combining high productivity and a belkovost. It only indicates need of control over the content in protein grain at all stages of selection.
On a grain belkovost strong influence is rendered by weather conditions, and among the agrotechnical receptions influencing this indicator, two are allocated with the productivity, generally: predecessors and fertilizers. The researches executed in IZH UAAN and other scientific institutions, it is convincingly shown that doses of brought fertilizers and initial level of providing plants nitrogen it is possible to regulate interrelation between size of a grain yield and the content of protein in it.
The contents and composition of proteins sharply change depending on soil climatic conditions, features of the agrotechnology, sowed hybrids and applied fertilizers. Among climatic factors in the greatest measure influence the content of protein in grain of a condition of moistening: than less than moisture and the temperature is higher, the content of protein is higher than subjects. So, grown up in a steppe zone of Ukraine the corn contains in grain for 1-2 % of protein more than its similar hybrid which has been grown up in the Forest-steppes and Polesye. Such changes are connected with transpiratsiya increase under the influence of high temperature and low relative humidity of atmospheric air. However, in this case it is necessary to note also that very strong decrease in humidity of the soil, to 35 % of PPV, is on the contrary accompanied by weakening of intake of nitrogen in plants. Therefore in years when during formation, naliva and maturing of grain there are soil and air droughts, its contents in vegetative weight becomes the main source of intake of nitrogen in grain. In that case when the soil contains enough of mobile forms of nitrogen and water, especially during time naliva grains, crucial importance in grain supply by nitrogen will belong to root system. It testifies that the content of protein in grain of corn changes under the influence of cultivation conditions. But in these conditions increase oho the contents grows out not of synthesis strengthening, and braking of adjournment of starch in grain. In this case high temperature of air strengthens breath of plants, promotes excessive expenses of carbohydrates owing to what protein accumulation in grain increases. At lower temperature breath of plants is weakened and increases accumulation of carbohydrates.
Quality of grain, is generally created during the period naliva grains when products of photosynthesis are transformed to spare substances. Therefore during this period plants need the increased nitric food, i.e. providing with their azotsoderzhashchy mineral nutrients in optimum quantity. And at their deficiency in the soil nitrogen in grain will mainly arrive from vegetative bodies of plants that is usually observed during the second period of vegetation when grain is formed. By this time in the soil usually the content of mineral nitrogen low, and protein of grain is formed, first of all, by mobilization of nitrogen of vegetative parts of a plant (leaves, stalks). These two sources of supply of plants are mutually connected by nitrogen, but aren’t equivalent. From the soil during this period nitrogen arrives in grain, generally in a mineral form, while from vegetative weight – mainly in an organic form. That is why it is important to provide an optimum nitric food in the course of all vegetation of corn, and also to combine the main application of fertilizers with nitric podkormkami.
In process of grain maturing in it the maintenance of a crude protein and, respectively, albuminous nitrogen decreases at simultaneous increase of starch. It is possible to explain it strengthening of process of receipt in grain at the last stages of its development of carbohydrates (the general sugars). The content of fat raises also. In process of grain maturing in it the maintenance of cindery elements and cellulose naturally decreases. The small content in the ripened grain of water-soluble substances provides its good stability to defeat by microorganisms at storage.
For the twenty years’ period, from 1986 to 2006, at Erastovsky experimental station of IZH UAAN more than 40 field experiments, including 5 stationary during which the questions connected with fertilizer agrocenozov of corn were studied were carried out. In each of them considered efficiency of fertilizers in crops of corn and at the same time annually selected practically by all options of experiences grain samples in which defined the main biochemical indicators of its quality.
Generalization of the experimental material collected so far showed that direct influence on education and protein accumulation in grain renders only nitrogen. Unilateral strengthening of a phosphoric and potash food or doesn’t influence the content of protein in grain, or reduces it. But such action of these elements on accumulation of protein is indirect, it is mediated by change of size of a crop. It, of course, at all doesn’t mean that phosphorus, potassium both others macro – and microcells aren’t necessary for protein synthesis in a plant. They are absolutely necessary, t.k their shortcoming brakes formation of protein in plants therefore their growth is slowed down and the crop decreases. But for the characteristic of quality of grain the absolute amount of protein in grain from hectare, and its percentage in grain is important not.
Positive correlation dependence between the content of the general nitrogen in plants in a phase of 5-6 leaves and the content of protein in corn grain (is established to r = 0,408 – 0,904). The interrelation analysis between the content in grain of protein and its aminokislotny structure showed that the increase in level of a nitric food leads to growth of the content in protein grain, but it is carried out, first of all, at the expense of its spirtorastvorimy fraction – zeina. This fraction of protein, unfortunately, defective as doesn’t contain in the structure of a lysine and has only traces triptofana.
Quality of grain of corn is influenced optimum by full mineral fertilizer. At gradual increase in the content of nutrients in the soil amount of the general nitrogen in grain and its belkovost increase. By researches it is established that by optimization of a mineral food and, first of all, nitric, it is possible to raise the content of protein in grain for 1-2 %, and also to provide increase of productivity of grain of early ripe and sredneranny hybrids to level mid-season and srednepozdny. But it is for this purpose very important to create conditions of good security of plants nitrogen in grain formation. The carried-out researches allow to draw the following conclusions:
1) optimum conditions for receiving grain with the high content of protein is good security of plants with the nitrogen, some deficiency of moisture and the increased temperature during the period naliva grains;
2) at improvement of conditions nitric pitaniyarasteniye by application of mineral fertilizers the increase in the content of protein in grain goes, generally at the expense of invaluable in the fodder relation of zeinovy fraction, at the expense of this factor it is possible to raise the content of protein in grain for 1-2 %.
S. Kramaryov, main research associate of laboratory of agrochemistry and soil science of Institute of a grain farm of UAAN, doctor of agricultural sciences.