INFLUENCE OF TECHNOLOGY OF GROWING ON YIELD AND OIL CHEMICAL COMPOSITION OF LINSEED IN NON-CHERNOZEM ZONE OF RUSSIA

The influence of the level of mineral nutrition and rate of seed sowing on yield and fatty acid composition of linseed (Linum usitatissimum L.) in the Non-chernozem zone of Russia was studied. It was shown that the level of mineral fertilizers of N – 90, P2O5 – 60, and K2O – 60 kg/ha under the rate of sowing of 8 million seeds/ha provided maximum seed yield of 1.94 t/ha. A clear correlation between oil content and rate of sowing has not been established. Under an increasing level of mineral nutrition, oil content was slightly increased. The composition of oil was slightly changed under the influence of the studied factors.


Introduction
Seeds of flax (Linum usitatissimum L.) are rich in polyunsaturated fatty acids, which are a source of energy and structural components of phospholipid cell membranes of tissues in humans.Flax seed is also a source of protein, soluble polysaccharides, phenolic acids and flavonoids, phytin, tocopherols, lignans and other biologically active components.Nutritional value of 100 grams of flax seeds consists of: 28.88 g carbohydrates (including 1.55 g sugars and 27.3 g dietary fiber), 42.16 g oil (including 3.66 g saturated fatty acids, 7.53 g monounsaturated fatty acids and 28.73 g polyunsaturated fatty acids, 18.29 g proteins, 1.64 mg thiamine (vitamin B 1 ), 0.16 mg riboflavin (vitamin B 2 ), 3.08 mg niacin (vitamin B 3 ), 0.98 mg pantothenic acid (vitamin B 5 ), 0.47 mg vitamin B 6 , 0.6 mg vitamin C, 255 mg calcium, 5.73 mg iron, 392 mg magnesium, 642 mg phosphorus, 813 mg potassium, 4.34 mg zinc (USDA, 2011).Due to the high content of various biologically valuable substances seeds are an excellent component of food supply having healing properties.
In the Russian Federation, flax seed is available for oral usage as enveloping and emollient to reduce irritation in inflammatory and ulcerative processes of the mucous membranes of the gastrointestinal tract, as well as for external use in the form of compresses and poultices in different local inflammation processes.Flax seeds are used as an antitussive, as a laxative for the treatment of chronic constipation, in the diet for people with diabetes.Flax seed is also used as a component of a number of herbal medicinal products for treatment of certain types of breast, prostate, stomach, gynaecological and inflammatory diseases, and also for treatment of anemia, asthma, gastritis, hyperthyroidism, urethritis, nephrosclerosis.Flax seeds can also be used in various forms of diabetes in order to stabilize the concentration of sugar and lower cholesterol in blood.
At the same time, the volume of production of plant oil in Russia is not enough what causes a need to increase the amount of oil seed crop production.The main oil crops in the Non-chernozem zone of Russia are spring rape and sunflower.Sunflower for oil production is grown on small areas.This is due to the long period of its vegetation.In some years the seeds of sunflower do not mature, plants are often infected by diseases, and they are not tolerant to acidic soils.Spring rape, due to damage by a large number of pests and diseases, requires intensive chemical protection, which significantly increases the cost of production of oil seeds.Therefore, in addition to traditional oil crops, it is necessary to introduce some other oil plants into production, in particular linseed (FAO, 2011).
It is known that the introduction of new cultivars characterized by high yield and resistance to unfavorable environmental factors has great economic importance, as it is accessible and cheap way to increase agricultural production, including linseed.In the Non-chernozem zone of Russia experience of linseed cultivation is still at an experimental level and in commercial conditions in a number of farms of Ryazan region it shows that the seed yield of the crop can reach up to 20 t/ha and above (Vinogradov and Artemova, 2010;Vinogradov et al., 2012a).
For the first time in the Non-chernozem zone of Russia in 2007-2012 we carried out comprehensive investigations on the cultivation of linseed cultivar 'Sunlin', studied the characteristics of growth and development, yield, and chemical composition of seed depending on rate and date of sowing and level of mineral nutrition.

Material and Methods
Experiments were carried out at Agrotechnological Station of Agrotechnological Ryazan State University named after P.A. Kostychev.Soil in experimental plots was gray forest medium loamy, content of humus was from 3.6 to 3.8%, phosphorus 169 mg/kg, potassium 132 mg/kg, and exchange acidity (extract of potassium chloride) 5.7 -5.8.
Previous crops were winter cereals.Common agricultural practices for this area have been used and they have been done in optimal time.The following mineral fertilizers were used: ammonium nitrate (34.25% N), double superphosphate (49% P 2 O 5 ) and potash (40% K 2 O).Linseed was studied at the following mineral nutrition levels: N -60 kg/ha; N -60, P 2 O 5 -60, and K 2 O -60 kg/ha; N -90, P 2 O 5 -60, and K 2 O -60 kg/ha; N -120, P 2 O 5 -60, and K 2 O -60 kg/ha.As a control the plot without fertilizer application was used.Mineral fertilizers were added under pre-plant cultivation.
Sowing was carried out in the first decade of May and drilling depth of seeds was 2 cm.Harvesting was organized mechanically and manually in the dead ripe stage.
An investigation of the efficiency of herbicides and their tank mixtures on the treatment of linseed plants of cultivar 'Sunlin' was carried out in the period of plant length near 7-8 cm by: 1) Agritoks in a dose 0.8 L/ha + Panther -1 L/ha; 2) Pruner-Turbo -0.1 L/ha + Panther -1 L/ha; 3) Cortez -6 g/ha + Harmani -20 g/ha; 4) Lenok -0.01 kg/ha.Fluid consumption rate was 250 L/ha.The survey and monitoring during the growing season were carried out on the basis of "Methods of cultivar testing of agricultural crops" (Dospehov, 1979).

Results and Discussion
The rate of sowing and level of mineral nutrition affect the phenological phases of plants.Fertilizing increased inter-phase periods and increased the length of vegetative period for 3 -6 days.The effect of nitrogen fertilizer on the linear growth of the plants began to manifest in a phase of 'christmas tree'.From this period up to the flowering phase there was a rapid growth of plants.After flowering, the linear growth of plants was usually stopped.When increasing doses of fertilizers, especially nitrogen, there was an increase in the leaf area.
During our investigations linseed plants had greater heat requirements, especially in the period of maturity.At low temperatures, germination of seeds and growth of seedlings became significantly slower.In the first period of growth, before flowering, the plants endured drought well.
From sowing to maturity linseed plants go through several successive phases of development associated with morphological changes in the structure and the formation of new organs (leaves, stems, reproductive organs).During the life cycle of linseed plants, there are the following phases of development: seedlings, 'christmas tree', rapid growth, budding, flowering, and ripening.The maximum growth of above ground dry matter weight was observed in the period from the rapid growth phase to the flowering stage.After that it decreased as a result of physiological processes.
Plants of cultivar 'Sunlin' were of average height and with dense foliage.Intensive root growth was marked at the early phases of development.
The period from sowing to seedlings, on average, lasted no more than 8 -10 days in the soil temperature 7 -8°C.For the germination seeds required about 120 -140% of water of its own weight, which is significantly less in comparison with many other crops.
During investigation the period from seedling to full maturity of plants was within 94 -117 days.There were considerable variations of the growing season length due to the difference of meteorological conditions of the years.Less warm weather and abundant rainfall lengthened growing season (2006,2008), and, conversely, warmer and less humid weather reduced the length of the growing season (2007,2010,2011).
Mineral fertilizers, particularly nitrogen, have increased the performance of the structural elements of yield.When increasing level of mineral nutrition the number of balls per plant and mass of 1000 seeds increased, which led to increasing of yield.
During investigations the yield of seeds ranged from 1.41 to 1.94 t/ha, depending on the studied factors.The highest yield was obtained in the variant with N -90, P 2 O 5 -60, and K 2 O -60 kg/ha and rate of sowing of 8 million seeds per ha (1.94 t/ha).All doses of fertilizers increased the yield of linseed.However, a high level of mineral nutrition and rates of sowing provided the highest yield.
At the same time, further increasing of the rate of sowing was less effective.The sowing rate of 10-12 millions of viable seeds per hectare caused selfshadowing of the plants, accompanied by decreasing of sowing quality of obtained seeds, increasing moisture of plants and seeds, especially at harvest period.In such variants, especially in dry conditions due to competition between plants there was worse capsule formation and they were smaller.Productivity of plants with high rate of sowing was lower even in comparison with the productivity of plants with rate of sowing of 4 million seeds per ha.
The use of herbicides reduced the contamination of crops, stimulated plant growth, and increased crop yield.Herbicide tank mixes have provided a significant increase of seed yield in relation to control variant.The greatest effect was observed when using Agritoks at a dose of 0.8 L/ha and Panther -1 L/ha (yield -2.29 t/ha) (Kuntsevich et al., 2013).A clear correlation between the change of oil content in the seeds and herbicide treatment has not been established (Table 1).
It is known that the oil content in the seeds of linseed and yield of oil depend on the cultivar.In our experiments content of oil in the seeds was within 39.9 -43.5%.It was noted that a clear correlation between oil content and rate of sowing has not been established.However, oil content was slightly increased with the increasing of doses of mineral fertilizers (by 0.5 -0.7%).Linseed protein contains many different amino acids.The protein of 'Sunlin' cultivar has a unique set of essential amino acids, especially it has a high content of threonine and isoleucine.Such high content of these amino acids in the protein was not found in any of the studied oil crops (Table 2).One of the main indicators of oil quality is its fatty acid composition.Linseed oil is low in saturated fatty acids (Vinogradov et al., 2010;Vinogradov et al., 2012b).Vegetable oils are rich in unsaturated fatty acids (linoleic, linolenic acid, oleic acid) which are not produced in the human body.They are biologically more valuable than animal fats that are characterized by increased content of saturated acids (palmitic, stearic) (USDA; 2011).The content of unsaturated fatty acids in 'Sunlin' cultivar was in the range of 90.1 -91.5%.
The active component of linseed oil is linoleic fatty acid.The share of this acid in linseed oil varies considerably depending on the cultivar, growing conditions and period of harvesting.'Sunlin' cultivar is characterized by a low content of linoleic acid.Therefore, it can be cultivated for the production of food, medical and dietary linseed oil (Table 3).We have created some lines of linseed different not only in the complex of morphological and agronomic characteristics, but also in the composition of fatty acids (Table 4).In the future, on the basis of them it will be possible to develop new cultivars for different directions of use.In our experiments the quality of oil, according to the content of fatty acids in it, was changed a little regarding the studied factors.However, when using higher levels of mineral nutrition, the content of linoleic acid decreased.At the same time the content of linolenic acid increased up to 0.4 -0.6%.
The yield of oil in our experiments depended on crop yield.Therefore, growing cultivar 'Sunlin' with sowing rate of 8 million seeds per ha and using N -90, P 2 O 5 -60, and K 2 O -60 kg/ha provides the maximum yield of oil which reaches 962 kg/ha.

Conclusion
Using of fertilizers stimulated the development of plants and increased crop yields.A fertilizer provided a significant increase in seed yield in comparison with the variant without fertilizers.The most effective rate of sowing was 8 million seeds per ha.A clear correlation between oil content and rate of sowing has not been established.When increasing the level of mineral nutrition, oil content slightly increased.The composition of oil slightly changed under the influence of the studied factors.

Table 1 .
Elements of yield structure, productivity and oil content of linseed cultivar 'Sunlin' depending on herbicide treatment.

Table 2 .
Content of essential amino acids in the protein of oil crops (g/100 g of protein).

Table 3 .
Fatty acid composition of the oil in major oil crops.

Table 4 .
The concentration of fatty acids in the oil of some developed lines of linseed (%).