ISSN 2305-9397. Ғылым және білім. 2022. № 3-3 (68)____ _
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with the crop provides the highest stability of yield. With low phosphate content in the soil and
insufficient fertilizer application, the coefficient of yield variation can reach 20% [18,19].
The content of mobile phosphorus does not depend on vaporization, the amount remains low
at the level, decreasing with depth. Phosphorus is needed most by plants between stemming and
flowering. The phosphorus supply of rapeseed plants comes mainly from soil reserves (70-80%). For
more complete use of phosphorus by plants it should be at least 6-8 mg per 100 g of soil. Along with
the regular application of phosphorus fertilizers, maintaining the optimal content of mobile
phosphorus is possible through appropriate main soil tillage [20,21]. Over the years of research on
experimental variants, the content of mobile phosphorus varies in the upper 0-20 cm layer of
8.1-9.8 mg /1000 g of soil.
Conditions of crop moisture supply.
The accumulation of moisture usually occurs partly in the autumn period and mainly in winter
due to the use of winter precipitation. By the sowing of spring rapeseed plants in 2016, the reserves of
productive moisture in pure, zero and minimum vapors ranged from 57.6 to 88.5 mm, and were at the
level by the end of following in 2015 (Table 3).
Table 3 – Dynamics of productive moisture reserves in the soil by crops in the 0-100 cm layer 2015-
2017, mm
Predecessor
First crop, wheat
2015
Second crop, rapeseed
2016
Third crop, wheat
2017
before
sowing
before
harvesting
before
sowing
before
harvesting
before
harvesting
before
harvesting
St Clean ploughing
process
120.4
48.2
88.5
32.5
77.8
16.2
Zero ploughing process
111.5
43.1
84.6
36.4
70.4
18.1
Minimum ploughing
process
113.6
46.4
82.3
37.2
71.6
17.8
Occupied ploughing
process
88.4
42.5
72.3
24.5
65.6
16.0
Legume crop
80.9
35.2
57.6
23.2
61.5
15.2
These variants of the experiment practically only retain the accumulated moisture during this
period, while all precipitation during the autumn-spring period is lost.
Crop yield. As noted above, the methods of preparing precursors had an impact on the content
of productive moisture in the soil. Over the years of research, yield data indicate a positive effect of
various methods of preparing precursors on the yield of spring wheat and rapeseed.
Table 4 – Yield of spring wheat and rapeseed in a four-field crop rotation, c/ha 2015-2017
Predecessor
Yield, c/ha
Average
deviation
from control
for rotation,
±
first crop,
wheat
2015
second
crop,
rapeseed
2016
third crop,
wheat 2017
1
2
3
4
5
6
St Clean ploughing
process
14,4
14,0
12,5
13,6
-
Zero ploughing
process
16,8
17,1
14,5
16,1
+2,5
Minimum ploughing
process
16,7
17,3
14,7
16,2
+2,6
Occupied ploughing
process
13,8
15,7
13,4
14,3
+0,7
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