Сельское хозяйство/3. Земледелие, грунтоведение и агрохимия

Candidate of Agricultural Sciences Shilov M.P., 4rd year student of ABF

Lyubimova E.V.

RSE «Kostanay State University named by A.Baytursinov», Kazakhstan

The effectiveness of nitric fertilizers having NO-TILL technology in droughty temperate steppes of Northern Kazakhstan

Introducing saving-resource technologies of agricultural crops cultivating based on zero tilling is a modern direction at the steppe farming. At the same time it brings to have the ability to low nitric-mineralized of black soil and generates a need to put nitric fertilizers into the fallow corn of crop rotation. In this regard the sample black soil of Kostanay region was examined to identify the effectiveness of different doses of nitric fertilizers for wheat after the second pair in the rotation fallow - spring wheat-wheat-wheat.

The experiment is used the chemical fallow with herbicide gliphosate. It is eliminated all the mechanical processing of wheat in crop rotation. Chaff was milled and spread over the surface the soil on fields everywhere. Nitric and phosphorus fertilizers were put into aisles with the sowing complex. Such fertilizers were used as the amount nitrate (at the rate of 34 %) simple granular superphosphate (at the rate of 19,5 %). The nitrate nitrogen was determinate by the ionometric method in a soil and mobile phosphorus on Machigin. Experimental design presented in table 1.

The researches of nitric conditions showed that the provision the check variant was low with a nitric which had a content on the basis of 6,3 mg/kg equal 0-40 in a layer before sowing wheat the second time (table 1). This figure usually amounts 12-15mg/kg during normal processing zone and rates as medium and high. Obviously, such reduction happens due to sharp suppression of nitrification process on zero tilling.

Table 1

The dynamic of being nitrate nitrogen and agility phosphorus in the soil on wheat growth stage, on the basis of mg/kg (average for 2011-2012)

Variant	Development phase			Average per the season
	Sowing	Outlet to the tube	Harvesting
1. Chaff 2,0 t (control)	6,3/13,4	3,4/13,1	3,2/13,2	4,3/13,2
2. Chaff 2,0 t + P20	6,4/15,2	3,7/13,8	3,0/13,5	4,2/14,2
3. Chaff 2,0 t + N30	8,8/13,7	8,5/14,6	5,2/14,0	7,5/14,1
4. Chaff 2,0 t +N30 P20	9,7/15,0	9,2/15,9	4,8/14,8	8,0/15,2
5. Chaff 2,0 t +N45 P20	10,8/15,4	11,2/16,2	5,6/15,3	9,2/15,6

*numerator - N-NO₃ in the 0-40 sm soil layer, denominator – P₂O₅ in the 0-20 sm layer.

Using of superphosphate P₂₀ recommended dose had no effect at the nitrogen content to sowing the amount was at the control level on the basis of 6,4 mg/kg. The situation has changed when nitrogen fertilizer is applied at a dose of N₃₀. The nitrogen content in the soil is increased from 34 to 44% and reaches the value of 8.8 mg/kg. But it does not change the gradation of security, it remains low, but it can significantly make effect on a growth as a whole and on the development of plant, especially in the initial phase of growth with poor root system developing. Putting P₂₀ intensifies the process of production of nitrates by 10 percent; it gives the opportunity to bring the number up to 9,7 mg/kg. However, only nitrogen dose changes the limits of supply on the basis of 45 kg a.s. and the limit increases its content to 10.8 mg/kg with soil transformation into average gradation.

The content of nitrogen falls steeply to 3,4 and 3,7 mg/kg with the bringing of some form of phosphate fertilizers (P₂₀) in the phase of the tube exit under control. It is impossible clarify only such a reduction near from 54 to 60 % using wheat plant. Obviously, most of the soil nitrogen is absorbed by microorganisms in the decay straw. This decline does not occur when applying nitrogen fertilizers. So at a dose of N₃₀, both separately and in combination P₂₀, there was no significant reduction of nitrate nitrogen – 8,5-9, 2 mg/kg. Further increase of the dose (N ₄₅) even increases the amount - 11.2 mg/kg. Obviously, an additional application of nitrogen in the soil is not only a source for the microorganisms, but also enhances the process for nitrification. All this eventually increases nitrogen nutrition wheat and further reduces its yield.

The availability of nitrogen phase of booting to harvest virtually unchanged and remained very low is from 3,2 to 3,0 mg/kg before harvesting wheat on the options with the introduction of straw, both separately and phosphate fertilizers. The amount during nitrogen fertilizer embedding was slightly higher. It’s from 4,8 to 5,6 mg/kg, which can positively affect the grain filling.

The dynamics of phosphorus regime in the experiment was much less pronounced. It’s substantially the same 13,4 and 13,2 mg/kg on the control version of mobile phosphorus content before sowing and harvesting period, which is characterized by low degree of security of this element. Superphosphate (P₂₀) adding changes the low level of provision on average one, with is 15,2 mg/kg. However, these changes occur only at the time of application them, though its amount decreases to a low level again is 13,8 mg/kg and remains unchanged for harvest is 13,5 mg/kg in the phase of booting. Although there is no significantly alter the phosphorus mode with implementation of nitrogen fertilizer, but it brings in some features of the dynamics. Therefore, the dose amount of available phosphorus N30 embodiment corresponds to the control is 13,7 mg/kg before sowing. However, the content of wheat is increased by 7 % and 14,6 mg/kg in the phase of booting. Apparently, nitrogen fertilizers increase soil microbial activity, which leads to additional release of phosphorus from the hard-to-reach connections. This process passes when a joint application of nitrogen and phosphate fertilizers is most active. This contributes to the fact that on the options N₃₀P₂₀ and N₄₅P₂₀ security and phosphorus was at the average level throughout the growing season of wheat in the end.

Marked features impacted on the productivity of wheat in the conditions of mineral nutrition (table 2). So, the least yield was got on control variant and was amounted 14,1 c/ha, that explained as low ensure of nitrogenous and phosphorus to all growth stage of cultivation.

Table 2

Making the effect of different doses of nitrogen fertilizers on the yield of spring wheat, с/ha (average for 2011 - 2012).

Variant	Yields, с/ha	increase grain		Payback 1 kg active substance (a.s.) by grain, kg
		с/ha	%
1. Chaff 2.0 tones (control)	14,1	-	-	-
2. Chaff 2.0 tones + Р20	15,1	1,0	7	5,0
3. Chaff 2.0 tones +N30	15,9	1,8	12	6,0
4. Chaff 2.0 tones +N30P20	18,4	4,3	30	8,6
5. Chaff 2.0 tones +N45P20	19,3	4,8	36	7,3
LSD05	0,9	-	-	-

Although the separate introduction of the P₂₀ and N₃₀ increased yields, respectively by 1,0 c (7%) and 1,8 y (12%), but their action was ineffective. Joint their using increases the productivity of wheat to 18.4 с/ha sharply, while the increase relative to the control reaches 4,3 с/ha or 30%. Increasing doses of nitrogen in combination up to 45 kg a.s. had no big effect on productivity growth. Compared with the previous version of grain growth was only 0,5 с/ha.

The choice of rational dose nitrogen-phosphorus fertilizers is derived from analysis of recoupment by 1 kg a.s. of fertilizer grain wheat. This figure was the best option for N₃₀P₂₀, where 1 kg of batteries was paid off in 8,6 kg of grain. Only 1 kg of fertilizer produced only 7,3 kg of grain by N₄₅P₂₀ on the background despite continued growth yield. The separate putting of N₃₀ and P₂₀ had the lowest rate of recoupment, respectively it was only 5,0 and 6,0 kg.