MICROHUMIN EFFICIENCY AT GROWING OF HULLESS OAT OF SKARB UKRAINY VARIETY AT DIFFERENT LEVELS OF NITROGEN NUTRITION OF PLANTS

It was shown that pre-sowing seeds treatment of hulless oat with Microhumin preparation can reduce the dose of nitrogen fertilizer on 20 kg/ha by reactant. The highest yield increase – 0.65–0.77 t/ha was received in the variants with N20P60K60 and N40P60K60 background. Additional yield in variants with inoculation and under N60P60K60 dose of fertilizer was 0.5 t/ha. It was established that yield increase was obtained mainly due to the higher grain mass and index of productive tillering.

Currently the world area under oat exceeds 25 million hectares. In Ukraine oat are grown as supporting fodder grains. Sown area of oats during the recent years has ranged within 300 -450 thousand hectares, while its main growing areas are concentrated in Polyssia and the Carpathian Mountains. The largest producers of grain oats for many years had remained Chernihiv region -about 130 thousand tons per year, Zhytomyr region -85-90 tons and Sumy region -80-85 tons [1].
Along with hulled oats the hulless oat is becoming more important for agricultural production and processing industry. The yield potential of modern varieties of hulless oat is about 5-6 t/ha. Crops can be used for food and fodder purposes without processing, which reduces labor and production costs.
The high price of commodity grain of hulless oats in foreign markets (200-240 USD/t), and the big importance of this crop on the Ukrainian market, including baby foods, requires optimization of cultivation technologies, including fertilization system, maximizing the level of its biologization.
Thus, the aim of our study was to determine the possibility of using microbial preparation Mikrohumin as an alternative to certain fertilizers dose in cultivation technology of hulless oats.
Materials and methods. Experiments were carried out on sod-podzol loamy light cultivated soils of Institute of Agricultural Microbiology and Agricultural Manufacture NAAS. The soils were formed on the layered water-glacial deposits. By the particle-size composition of parent-material horizons of sod-podzol soils of the area are sandy loam and light sandy loam soils.
A characteristic feature of sod-podzol sandy loam soils is homogeneous of its mineralogical composition with quartz domination. It results in significant permeability of the soil profile, low buffering, poorness of parent-material horizons with mineral nutrients, magnesium and calcium, low absorbing ability in relation to exchange cations, unstable structure, tendency to crust formation, soil capping and poor microbiological activity. That causes significant cost of farming practices, including cost of fertilizers.
Fertilizers were applied in the form of ammonium nitrate, superphosphate and potassium chloride. Phosphorus-potassium fertilizers were applied in autumn, while nitrogen -at crop cultivation.
Mikrohumin, used in the experiment, is a complex biological preparation based on the bacteria of Azospirillum genus and extract of vermicompost, which contains physiologically active substances. Besides compounds of hormonal action, vermicompost contains vitamins, macro elements and trace elements in chelate forms due to their interaction with the available in vermicompost amino acids and organic acids, including humic and fulvic acids. It should also be noted, that due to the intensive development of microorganisms substrate accumulate polysaccharides of bacterial origin during vermicomposting of organic matter. Preparation dosage -200 grams per hectare seed rate.
Cultivation techniques for hulless oats were common for the area. Variety -Skarb Ukrainy. Seeding period -second decade of April. Seeding rate -Results and discussion. The average data for three years of research indicate that complete application of mineral fertilizers N 60 P 60 K 60 had ensured 3.4 t/ha of oats yield which was 2.4 times above the productivity in control variants -1.44 t/ha. Reducing of nitrogen dose to N 40 had caused yield decrease on 0.38 t/ha or 11 %, while lowering of nitrogen fertilization dose to N 20 had resulted in -0.87 t/ha or 26 % decrease.
Yield increase in variants with Mikrohumin inoculation had ranged from 0.50 to 0.77 t/ha and was the largest in variants with low doses of nitrogen N 20 -N 40 (Table 2). Pre-sowing seeds inoculation with Mikrohumin had ensured 1.94 t/ha of yield in control variant and 3.90 t/ha in variant with full dose of fertilizer N 60 P 60 K 60 that was two times greater than in control. Exclusion of nitrogen had resulted in yield decrease to 2.56 t / ha (34 %), application of N 20 dose -to 3.18 t/ha (18 %), and N 40 dose -to 3.79 t/ha (3 %).
The hulless oats yield within 3.02-3.18 t/ha was obtained both at application of 40 kg/ha of mineral nitrogen dose and Microhumin inoculation on N 20 P 60 K 60 background, indicating the equivalence of the impact of the inoculant to no less than 20 kg/ha dose of mineral nitrogen. Observed features were also confirmed by grain yield ranging within the 2.56-2.53 t/ha in variants with phosphorus-potassium fertilizers (N 0 P 60 K 60 ) and seeds treatment with Mikrohumin and N 20 P 60 K 60 fertilizer dose without inoculation. At the same time, the N 40 P 60 K 60 dose of nitrogen combined with inoculation was more effective than application of N 60 P 60 K 60 . At this yield increase was 0.39 t/ha (Table 2).