Длительное 32-летнее применение удобрений на плодородие чернозема обыкновенного и продуктивность сахарной свеклы | LONG TERM 32-YEAR-OLD APPLICATION OF FERTILIZERS FOR THE FERTILITY OF THE ORDINARY BLACK SOIL AND PRODUCTIVITY OF SUGAR BEET

The article deals with the effectiveness of mineral and organic fertilizers in long-term application (for more than thirty years) according to the influence on the fertility of ordinary black soil of the Western Ciscaucasia and productivity of sugar beet. The investigations were carried out in the long-term stationary experiment laid on the experimental stationary section "Severokubanskaya agricultural experimental station" of P.P. Lukyanenko Krasnodar Agricultural Research Institute. The experiment was laid simultaneously in time and space in two ten-course crop rotations and combined grain-grass tilled. In the structure of sown areas sugar beet occupied 10% of crop rotation area and was placed after the winter wheat. During three rotations it was studied: 1- control without fertilizer with natural forming level of mineral nutrition; 2- minimal dose N21P26K16 3- medium dose N43P52K33 ; 4 - N43P52K33, 5- high dose N96P104K68; 6- organo-mineral system¹ N43P52K34 + 12 t/ha of manure; 7- organo-mineral system² N20P24K34 + II-III rotations tillage of straw crop + 6 t/ha of manure; 8- medium dose P52K33; 9- medium dose N43K33; 10- medium dose N43K52. The soil which is used by organo-mineral system with increased and high standards of mineral fertilizers had higher concentration of mineral nitrogen. Long systematic application of fertilizer had more noticeable effect on soil phosphorus regime. The provision of soil by exchange potassium tended to decline from rotation to rotation. If at the completion of the first rotation the content of this battery was at the level 362,0-433,0 mg / kg of soil, in 2010, these values were 356,0-405,0 mg / kg of soil, remaining at the level of increased and high provision characterized to ordinary black-soil. Fertilizers for crop rotation provided almost equal yield increase: in the first rotation - 4,9-16,0 t / ha in the second 5,3- 17,1, the third 6,1-15,5 t / ha. In the moderate favorable for moisture and temperature conditions during the first and third rotation (hydrothermal index 0,8- 0,76), the value of sugar beet yield was 30,1-46,1 and 35,7-52,1 t / ha, in comparison with tougher conditions for the second rotation (hydrothermal index 0,41- 1,96) higher up to 2,6-6,5 9,2-16,0 t / ha. Research carried out in long-term stationary experiment showed that long-term use of fertilizers prevents to the loss of soil organic substances, supporting the humus content at the level of 3.95-3.99%, and organicsystems contribute to its reproduction to 4,01-4,21%. soil nitrogen state is stabilized. However, there is a tendency of decrease of the exchange potassium in mineral fertilizer systems. In the conditions of insufficient moisture supply of the northern zone of Krasnodar region the most applicable norm is N60P90R60, both in mineral and organic-systems, ensuring the collection of root crops within 43,0-45,2 t / ha, with an estimated amount of sugar 6,92-7, 14 t / ha. The given systems of fertilizer provide the yield of root crops 53,3-56,0 t / ha with the synthesis of sugar 8,19-8,70 t / ha. Increasing the rate of fertilizer in 2 times from medium to N120P160R120 doesn’t increase the productivity, reduce sugar content of root crop to 0.4-0.8%. It is undesirable to use fertilizer that are unbalanced in nutrition elements in which root crops yield declines from 5.4 to 19.0%, and current biological sugar from 6,1 to 25,9%