Crop yield indicators. B

Determination of TLD based on qualitative assessment of soil

The determination method was proposed by the Belarusian Research Institute of Soil Science and Agrochemistry:

TLD = Bp*Cb*K (13)

Bp – soil quality, point;

Cb – price of arable land point, kg;

K – correction factor to the point price for the agrochemical properties of the soil.

TLD =32*50*0.94=15c/ha

Determination of programmable yield (PrU).

The value of the programmed yield is determined taking into account the difference between the COU and the TLD, which is compensated by introducing calculated doses of mineral and organic fertilizers. Thus, the programmed yield is calculated as a TLD with the increase in yield that should be obtained through fertilizers.

PrU – programmable yield, c/ha;

Дnpk – dose of mineral fertilizers, kg/ha;

Оnpk – payback of 1t of organic fertilizers, kg/t of product;

100 – conversion factor from kg to c.

The PrU level can also be determined by knowing the relative increase from fertilizers:

(15)

Pood – increase in yield from fertilizers, %

Thus, the yield of spring barley of 32 c/ha will be a guideline for the development of a structural model of a highly productive plant and sowing in general, as well as crop cultivation technology.

Table 7. Calculation of fertilizer doses for the programmed harvest based on the removal of nutrients. The yield of spring barley is 32 c/ha

Lit. designation	Indicators	Unit measured
	Removal of nutrients from the soil by one centner of crop
	The total removal of nutrients necessary to obtain the programmed harvest (Bo=B*U)
	Soil nutrient uptake coefficient
	The amount of nutrients received by plants from the soil (Ip=P1*Kp*0.1)
	Added organic fertilizers
	Nutrients entered into the soil with manure (Np=10*Sm*O)
	Coefficient of nutrient absorption of organic fertilizers (per year of crop cultivation)
	Nutrients from organic fertilizers will be used by plants (Io=Np*K1-2*0.1)
	The total amount of nutrients that plants can receive from soil and organic fertilizers (I = In + Io)
	It is necessary to add nutrients with mineral fertilizers (D=Wo-Ip)
	Coefficient of nutrient absorption of mineral fertilizers
	Dose of mineral fertilizers that must be applied taking into account their utilization rate (Dm=D:Km*100)
	Contains nutrients in fats
	Application rate of mineral fertilizers (Mu=Dm:St)

As can be seen from the table, the calculation of doses of mineral fertilizers is carried out taking into account the content of nutrients in the soil, taking into account the elements that entered the soil with mineral fertilizers, as well as taking into account the coefficient of their absorption by plants. To obtain the programmed yield, according to the calculation data, it is necessary to add 44 kg/ha of nitrogen in the active substance, 33.5 kg/ha of active ingredient phosphorus, 33.5 kg/ha of active ingredient to the soil. potassium This will be equal to the application of: 2 c/ha of UAN, 2.4 c/ha of simple superphosphate and 1 c/ha of potassium chloride.

Crop productivity is the main factor that determines the volume of crop production. When analyzing productivity, it is necessary to study the dynamics of growth for each crop or group of crops over a long period of time and identify reserves and opportunities for its further growth.

The yield level is the result of the influence of three complex factors - agrotechnical, natural and organizational. It fluctuates from year to year. To identify its development trend, you can use the moving average method during analysis. In this case, 5-10-year data on the yield of a particular crop (or group of crops) is processed as follows: for the first 3-5 years, a simple average is calculated, then the date is shifted by 1 year and the average is determined again, etc. The resulting series usually shows an upward or downward trend in yield levels.

For example, in the analyzed farm over the past 7 years the following change in the level of grain crop yields has been observed:

1996 1997 1998 1999 2000 2001 2002

21,5 22,8 16,5 20,3 19,7 23,4 21,0

Until 1998, grain yields increased, and since 1998 they began to decline. However, such a conclusion is not entirely correct. Let us process this series using the moving average method.

Let's take the yield levels of the first three years and calculate the simple average, it will be equal to 20.3 c = (21.5 + 22.8 + 16.5) : 3. Then we will shift the date by one and again for three years (1997,1998, 1999) let's calculate the average, which will be equal to 19.8 c, etc.

As a result, we obtain a new dynamic yield series:

_____________________________________________________________

1996-1998 1997-1999 1998-2000 1999- 2001 2000 -2002

______________________________________________________________

20,3 19,8 18,8 21,1 21,4

______________________________________________________________

Thus, during the period from 1996 to 2002, the yield of grain crops on this farm tended to increase; it increased by 1.1 c (21.4 - 20.3).

Productivity is a quantitative, complex indicator that depends on many factors. Natural climatic conditions have a great influence on its level: 1) air temperature, 2) groundwater level, 3) amount of precipitation, 4) quality and composition of the soil, 5) terrain, etc. Therefore, when studying the dynamics of yield, it is necessary to take into account agrometeorological features of each year during the growing season and harvest.

All agrotechnical measures for growing crops, as well as high-quality execution of all field work in a short time and other economic factors have a great influence on productivity. In the process of analysis, it is necessary to study the implementation of the plan for all agrotechnical measures, determine the effectiveness of each of them, and then calculate the impact of each activity on the level of yield and gross production. To do this, underfulfillment or overfulfillment of the plan for the volume of each activity is multiplied by the planned level of its payback, and the change in payback is multiplied by the actual volume of the corresponding activity.

Thus, to determine the payback of fertilizers, three analysis methods can be used: experimental, calculated, correlation

The most accurate method is experimental. Its essence lies in the organization of field experiments. By comparing the yield of experimental plots where fertilizers were applied and control plots where they were not applied, it is possible to determine the increase in yield due to the applied fertilizers. However, this method is used only in experimental farms.

The majority of farms use a calculation method to determine the payback of fertilizers. According to this method, the calculation of additionally obtained products per 1 c of fertilizers is carried out in the following way: first, the yield from the natural fertility of the soil is calculated, for which the quality of the land in points is multiplied by the price of the point, which is determined by the regional agrochemical laboratory. Then the difference between the actual and estimated yield is divided by the number of applied fertilizers per 1 hectare of crops of a given crop and, thus, determine the increase in yield per 1 quintal of fertilizers (NPK)

Ok = (Uf – Ur): Kf, where

Ok – payback for 1 quintal of fertilizers,

Uf and Ur - actual and calculated yield levels;

Kf – the actual amount of fertilizer applied per 1 hectare of crop crops, centners

Calculation of payback of fertilizers

______________________________________________________________

Indicators Rye

______________________________________________________________

1. Soil quality, score 46

2.Price 1 point, c 0.36

3.Calculated yield level (from natural (46 × 0.36)

fertility c\ha 16.6

4. Actual yield, c\ha 25

5. Increase in productivity due to the application of fertilizers, c 8.4 (25-16.6)

6. Amount of applied fertilizers per 1 hectare, c 2

7. Actual payback of 1 c of fertilizer, c 4.2 (25-16.6): 2

8. Standard (planned) payback of 1 c of fertilizer, c 5.0

______________________________________________________________

These tables indicate that the payback plan for fertilizers when growing rye has not been fulfilled. A decrease in the payback of fertilizers can occur due to their imbalance, low quality, timing and methods of their application. Therefore, during the analysis process, all these reasons must be analyzed.

If there is a sufficient number of observations about the crop yield and the amount of fertilizer applied to it, correlation analysis can be used to determine the payback of fertilizers.

The increase in yield largely depends on the seeding rate, quality and variety of seeds. Reducing the seeding rate and the use of substandard seeds reduces crop yields. Therefore, during the analysis process, it is necessary to calculate how much the yield has decreased due to this factor. For example, if the norm is 450 plants per 1 sq. m actually sprouted 300, then we should expect that the yield of this crop will be lower than calculated by 20-30%.

In the process of analysis, they also find out which varieties are cultivated on the farm, and how timely variety change and variety renewal are carried out.

The yield of agricultural crops depends significantly on the applied crop rotations, which must be observed in each farm. In the introduction of crop rotations, there are two types:

1 - introduction, when the crop rotation project is transferred to nature, i.e. the fields are cut according to it;

2 - development, when the transition period is over, and agricultural crops are placed in the fields in accordance with the adopted scheme and crop rotation plan.

The structure of sown areas has a great influence on the average level of yield. For example, if among grain crops high-yielding crops have the largest share compared to the base year, then the average yield becomes higher.

To determine the effect of structure on the average yield level, you can use the index method using the following formula:

Device = ∑ У1 × S1 ∑ У1 × So

_________ : ___________

where: Y1 – yield of the reporting year, c\ha

S1 – area of ​​the reporting year, ha

So – base year area.ha

The timing of sowing and harvesting has a great influence on yield. The optimal time for sowing early grain crops is no more than 4-5 days, harvesting is 10-12 days. Deviation causes a decrease in yield.

The yield of agricultural crops, in addition to the listed factors, depends on a number of other agrotechnical measures: the quality and methods of soil cultivation, placement of crops in crop rotation fields, methods and timing of crop care, etc.

Programming is the development of a set of interrelated activities, the timely and high-quality implementation of which ensures the achievement of the planned yield. This direction in agronomy reflects the achievements of a large number of related sciences - plant physiology, agriculture, crop production, soil science, agrochemistry, meteorology, agrophysics, as well as mathematics, cybernetics and economics. The main goal of programming is to move to the widespread use in agronomy of quantitative models and electronic computing technology, which allows you to quickly process information about the factors affecting plant growth and select the best option for agrotechnical measures aimed at obtaining the programmed yield.

One of the main principles of modern agricultural production is the use of intensive farming methods to increase crop yields and product quality. Obtaining high yields of agricultural crops is possible only by creating optimal conditions for the transformation and metabolism in the plant body, starting from photosynthesis and ending with the formation of the final products of plant life.

For the continuous operation of green plant leaves, a constant flow of energy resources is required: light, various elements of mineral nutrition, water, heat, carbon dioxide and oxygen. An optimal combination of external factors is also necessary: ​​soil fertility, cultivation techniques, soil humidity and temperature, allowing plants to realize their potential.

The level of plant nutrition, the varieties used, cultivation technology and weather conditions are in close relationship, determining the amount of yield. A sharp deviation of any factor from the norm can be decisive and limit the achievement of high yields.

Obtaining the highest possible yield most often depends on unregulated, partially or difficult to regulate factors (light, heat, moisture supply), which can limit the growth and development of plants.

The missing amount of one or another factor can be compensated by appropriate agricultural techniques. Agricultural techniques can weaken or strengthen the influence of life factors on the growth, development of plants and crop formation.

The problem of increasing the production of grain and other agricultural products is solved mainly by increasing the productivity of arable land. This is facilitated by a new direction in agronomic science - yield programming. It is based on meeting the needs of plants for vital environmental factors and the targeted formation of crops to obtain a given yield.

Thus, the basis of the method of programming agricultural crop yields is the forecast of possible yields, as well as the development and practical implementation of crop cultivation technology that best suits its biological characteristics.

There are the following principles of crop programming (according to I.S. Shatilov):

The first principle provides for the use of hydrothermal indicators of the environment when determining the level of productivity.

The 2nd principle is taken into account when determining the potential yield of agricultural plants and is based on the dependence of the yield on the arrival of PAR and the coefficient of use of photosynthetically active radiation by plants.

The 3rd principle involves determining the potential capabilities of a crop and selecting varieties for cultivation in specific natural conditions according to their potential capabilities.

The 4th principle is the relationship between yield and the photosynthetic potential formed in the agrophytocenosis and involves the formation of such a photosynthetic potential that ensures a high yield.

The 5th principle presupposes the mandatory and correct application of the basic laws of scientific agriculture and crop production.

The 6th principle is to develop a fertilization system that takes into account the effective fertility of the soil, as well as the plant's need for nutrients necessary to produce a high-quality programmed crop.

The 7th principle is the development and application of a set of agrotechnical measures that takes into account the requirements of the crop (variety) for growing conditions, as well as the conditions of the agrometeorological situation. The precise implementation of the developed set of agrotechnical measures should ensure the production of the programmed harvest.

The 8th principle provides for providing plants with moisture in optimal quantities, in non-irrigated conditions - determining and maintaining the level of productivity based on climatic conditions and characteristics of the zone.

The 9th principle is the principle of mandatory protection of plants from pests, diseases, and weeds, ensuring the cultivation of healthy plants.

The 10th principle provides for the creation of a data bank on the biological characteristics of field crops, their growing conditions, experimental materials evaluating various agricultural techniques and operations, and the use of modern computer technology.

In the yield programming method, calculations lead to the following levels:

Potential yield (PU) – the maximum possible level of yield; limited by the arrival of PAR, its efficiency and the biological characteristics of the crop and variety.

Climatically ensured yield (CSY) is the yield that can be obtained in specific climatic conditions while optimizing all other factors of plant life. The COE is limited by climate elements and weather.

Really possible yield (TPU) is the maximum yield that can be obtained on a particular field, with its real fertility under prevailing meteorological conditions. TLD is limited by soil fertility.

Programmable (resource- and technically supported) yield (PrU) is the yield that is planned to be obtained on a specific field in accordance with a set of developed agrotechnical measures. The level of PrU is determined through the value of COU and TLU by optimizing the nutritional regime of the soil.

Productivity in production (YP) is the actual achieved level of productivity in a particular farm.

Determination of potential yield (PU)

The level of potential yield depends on the biological properties of the crop or variety; the amount of energy of passing photosynthetically active radiation and the amount of energy accumulated in the biomass of the crop; nutrients in the soil; level of agricultural technology and meteorological conditions.

The methodology for calculating PU based on the arrival of PAR and its utilization rate was proposed by prof. A. A. Nichiporovich:

Calculation of PU for the use of mid-level phased arrays:

PU – potential biological productivity of absolutely dry biomass, centners;

∑QPAR – income of the total PAR during the growing season of the crop in the zone, billion kcal/ha (kJ/ha);

K – planned efficiency of phased array;

q is the caloric content of 1 kg of dry crop biomass, kcal/kg (kJ/kg).

To obtain the PU of an economically valuable part of the crop, it is necessary to apply the following formula:

C – the sum of the components of the harvest (grain + straw);

In st – standard humidity.

Determination of climate-stable yield (CY)

The methodology for calculating moisture resources (MCW) is based on determining the ratio of the amount of moisture available to plants during the growing season and the total consumption of moisture to create a unit of crop:

t/ha or 51.5 c/ha,

KOUw – climatically ensured yield of the main products at standard humidity, t/ha;

Wms – moisture content of a meter layer of soil during the resumption of spring vegetation or before spring sowing, mm;

Ov.p. – amount of precipitation during the growing season, mm;

Ko is the coefficient of usefulness of precipitation;

Kw – water consumption coefficient, mm × ha/c or m³/t;

C – the sum of the parts of the main and by-products;

Vst – standard humidity.

Determination of climate-provided yield based on heat resources (COU t°)

The calculation method is based on a preliminary determination of the bioclimatic productivity potential (BPP) and is calculated using the following formula:

∑t°›10° – sum of active temperatures in the region;

1000° is the sum of temperatures at the northern border of agriculture.

Therefore:

52.9 × 1.15 = 60.8 c/ha.

- β – coefficient reflecting the level of farming culture and corresponding to the coefficient of PAR use, %: 1.0; 2.0; 3.0; 4.0 - respectively 10; 20; thirty; 40.

KOU t° – yield of absolutely dry biomass, i.e. feed. units/ha.

To determine the climate-provided yield based on heat resources, I needed the following calculation data:

Conversion factor of units/ha to c/ha = 1.15;

The sum of active temperatures in the region is more than 10°С = 2299°С

Determination of truly possible yield (TPL)

TLD is the level of productivity that can be achieved on a specific field, taking into account real soil fertility. The determination method was proposed by the Belarusian Research Institute of Soil Science and Agrochemistry:

Bp – soil quality, point;

CB – price of arable land point;

K – correction factor to the point price for the agrochemical properties of the soil.

Really possible yield with intensive cultivation technology:

TLD = 37 * 52 * 0.89 = 1712 t/ha or 17.1 c/ha.

Determination of programmable yield (PrU)

The programmed yield is determined taking into account the difference between the COU and the TEU, which is compensated by introducing calculated doses of mineral and organic fertilizers. Thus, PrU is calculated as a TLD with an increase in yield, which should be obtained through fertilizers. We determine the PrU level based on the increase from fertilizers using the formula:

PrU - programmable yield;

DNPK – dose of mineral fertilizers;

ONPK – payback of 1 kg NPK, kg of products;

Do.u. – dose of organic fertilizers, t/ha;

Oo.u. – payback of 1 ton of organic fertilizers, kg/t of product;

100 – conversion factor from kg to c;

Pood – increase in yield from fertilizers.

This formula can be written as follows:

Pud = 100 – Bp

Pud = 100 – 37 = 63

Programmable yield with intensive cultivation technology:

Increase in yield from fertilizers Table 3

In this section, we got acquainted with the basic methods of yield programming and made sure that:

Potential yield (PU) is the maximum possible level of yield (it is limited by the arrival of PAR, efficiency, biological characteristics of the crop), which is 172 c/ha, PU of the economically valuable part of the crop is within 80 c/ha;

Climatically ensured yield (CY) - the yield that can be obtained in specific climatic conditions (CY is limited by climate elements and weather), which is 62.3 c/ha;

Really possible yield (TPL) is the maximum yield that can be obtained on a specific field, with its real fertility in the prevailing meteorological conditions (TPL is limited by soil fertility), and is: with conventional cultivation technology 17.8 c/ha, and with intensive – 23.1 c/ha;

Programmable (resource- and technically supported) yield (PRU) is the yield that is planned to be obtained on a specific field in accordance with a set of developed agrotechnical measures (the level of the PrU is determined through the value of CUC and TD by optimizing the nutritional regime of the soil); this indicator in our case will be equal to 40.0 c/ha for cultivation using conventional technology, and 51.3 c/ha for intensive cultivation.

Crop types based on the state of the crops are determined by visually assessing the crops at different periods of their development. When assessing by eye, depending on the time of assessment, the density of seedlings, the degree of plant development, the degree of tillering, the corresponding density of plant standing, the size of the ear, etc. are taken into account. The assessment of crops is carried out by agronomic personnel and is expressed in a comparative qualitative characteristic (poor, below average, average, above average, good), points (1, 2, 3, 4, 5), centners, as a percentage of the average level.

Standing yield before timely harvesting can be determined in three ways:

• - eye-wise, by carefully inspecting the crops before harvesting (the so-called subjective method);
• - instrumentally, by selectively placing meters on crops before harvesting (objective method);
• - by calculating(by balance calculation method ) based on complete actual collection data and sample loss data.

The standing harvest before the start of timely harvesting and the barn harvest differ by the amount of actual losses. Therefore, knowing two of these three indicators, you can calculate the value of the third. However, standing yield and losses can only be estimated approximately. Therefore, balance equations between the noted indicators will have some kind of error in determining losses or standing crops.

Currently, statistics take the actual harvest as the main indicator. Until 1961, the amount of losses was determined selectively.

Both when assessing the standing crop yield and when analyzing the level of actual harvest per 1 hectare, it is necessary to clearly represent the constituent elements that directly determine the yield value. For example, the yield level of sugar beets depends on the number of plants (standing density) per hectare and the average weight of the roots, potatoes - on the number of bushes and the average weight of tubers per bush. For root and tuber crops, the value of these elements is often taken into account selectively when determining crop types. By comparing such values ​​with the corresponding standards for various stages of the growing season, a conclusion is drawn about the possible level of yield.

The yield level of cereal grain crops is composed of the following elements: the number of ears, the number of grains in an ear, the absolute weight of the grain. Therefore, having certain selective data on the value of these elements, grain yield per hectare in centners can be determined by the following formula:

U NK = K*Z*A 100000

Where TO-number of ears per 1 m2;

Z- number of grains in an ear;

A--absolute grain weight, i.e. weight of 1000 grains, g.

When assessing the yield on a farm by eye, areas with visible differences in yield are considered separately. After determining the yield for each field, the weighted average for the farm is found.

Species yield and productivity-- These are the sizes of the emerging crop and the emerging yield, established by the state of crops at certain points during the growing season, sometimes taking into account meteorological conditions and some manifestations of economic life.

For a long time, the assessment of crop yields has been included in the program of a special statistical report.

Harvest and standing yield represent the sizes of grown agricultural products, established before the start of timely harvesting. This category of harvest and yield of agricultural crops is determined either on the basis of a subjective generalized assessment for a certain date, or the results of selective imposition of meters on crops before harvesting or other materials. Yield and standing yield were also determined using a number of methods. So, for example, from 1947 to 1953, the determination of yield was carried out by the State Inspectorate for Determining Yields based on reports from collective and state farms on yields, the results of selective marking of crops before harvesting, data on yields at variety testing sites of the State Commission for Variety Testing Sites, meteorological materials stations, as well as information on the condition of crops throughout the growing season.

During this period, harvest and standing yield were considered the main assessment indicators of the level of development of crop production industries. Moreover, according to harvest and standing yield data, the amount of payment in kind for work performed by machine and tractor stations on collective farms was determined.

In subsequent years, the crop and standing yield were used for different purposes. On many farms, the size of the grown yield of a number of agricultural crops is determined during control threshing. Materials about this serve as a guide in harvesting work. State statistics bodies used data on control harvests among other materials in the study of losses during harvesting.

Under normal economic conditions harvest And normal economic productivity understand: harvest and standing yield minus the so-called normal losses at a given level of development of agricultural technology and production organization. From 1933 to 1939, these categories were considered basic in statistics. Gross harvest in the modern sense is the amount of collected and capitalized products from the harvested main, repeated and inter-row crops of certain agricultural crops. Since 1994, gross grain production in statistics has been taken into account as a final indicator in physical mass after processing (cleaning and drying). For ongoing monitoring of harvesting, gross harvest; is shown in the initially capitalized mass.

For vegetables in protected soil, the gross harvest is determined as the sum of products collected from all turnovers by type of structure. A general collection of vegetables from all types of protected ground structures is also established, as well as a general collection of vegetables from open and protected ground. The gross harvest of fruits, berries and grapes includes products collected not only from plantings at fruit-bearing age, but also from young plantings that have not been put into operation.

Average yield agricultural crops (harvest per 1 hectare) is determined by dividing the gross harvest from the main crops (without intermediate, repeated and inter-row crops) by the specified spring productive sown area of ​​these crops.

The fact that the spring productive area is used in the calculation stimulates the harvesting of the sown area. When calculating the average yield for the actually harvested area, it may turn out that a farm that allowed crops to die in summer, as well as left crops unharvested, will have a higher yield level compared to farms that completely harvested the entire sown area. For greenhouse vegetables, the average yield is found by dividing the gross harvest from all rotations by the used sown area for the first rotation. For perennial plantings, when calculating the average yield, the gross harvest from plantings at fruit-bearing age and the area of ​​only fruit-bearing plantings are taken into account, regardless of whether there was a harvest from these plantings in the reporting year or not.

Categories barn harvest And barn yield in statistics are interpreted ambiguously. It is believed that a barn harvest is a harvest that arrived in barns, warehouses and was recorded in one order or another. Or is it a harvest collected in the farm’s barns and documented. There is also an understanding of the barn harvest as the volume of harvest received by the farm. From 1954 to 1964, state statistics bodies published harvest data under the heading Gross harvest (barn harvest) of grain crops. In subsequent years, publications use only the term gross collection.

Harvest and yield are both forecast indicators.

Crop productivity is the main factor that determines the volume of crop production. When analyzing productivity, it is necessary to study the dynamics of its growth for each crop or group of crops, conduct an inter-farm comparative analysis, establish the degree of fulfillment of the plan for the yield of each crop and calculate the influence of factors on changes in its value.

Factors affecting yield
	Natural and climatic	Soil fertility
	Mechanical composition of the soil
	Terrain
	Temperature
	Ground water level
	Amount of precipitation, etc.
	Economic	Quantity, quality and structure of applied fertilizers
	Quality and timing of all field work
	Seed quality
	Changing the varietal composition of crops
	Liming and gypsuming of soil
	Control of plant diseases and pests
	Alternation of crops in crop rotation fields, etc.

In the process of analysis, it is necessary to study the dynamics and implementation of the plan for all agrotechnical measures, determine the effectiveness of each of them (yield increase per 1 centner of fertilizers, unit of work performed) and then calculate the impact of each activity on the level of yield and gross harvest of products. Let's consider the calculation method using the example of fertilizing fields.

Provision of the enterprise with organic and mineral fertilizers determined by comparing the actual amount of harvested and used fertilizers (statistical reporting on the use of fertilizers) with the planned need (calculation of fertilizer needs by crop).

At the end of the year it is calculated actual payback of fertilizers for each crop:

Ok = (U f - U r) / K f;

Where OK– payback 1 c NPK;

U f – actual crop yield;

Ur – yield from natural soil fertility without the use of fertilizers (according to

agronomic accounting data);

TO f – the actual amount of fertilizer applied per 1 hectare of crop crops, c NРК.

Reduced payback on fertilizers may occur due to their imbalance, poor quality, timing and methods of application to the soil.

Correlation analysis can also be used to determine the payback of fertilizers provided that there is a sufficient number of observations about the yield of the crop and the amount of fertilizer applied to it. Let's consider the calculation method using the data in Table 2.1.

Table 2.1. Initial data for calculating the dependence of barley yield ( Y) from the amount of fertilizer applied per 1 ha of crops ( X)

Field number	X	Y	XY	X 2	Y2	Y x
	1,5	18,0	27,00	2,25	324,00	16,5
	2,0	19,7	39,40	4,00	388,09	19,5
	2,2	20,8	45,76	4,84	432,64	20,7
	2,5	22,5	56,25	6,25	506,25	22,5
	2,8	22,3	62,44	7,84	497,29	24,3
	3,0	24,8	74,40	9,00	615,04	25,5
	3,5	25,4	88,90	12,25	645,16	28,5
	3,8	31,3	123,12	14,44	1043,29	30,3
	4,2	34,2	143,64	17,64	1169,64	32,7
	4,5	35,0	157,50	20,25	1225,00	34,5
Total	30,0	255,0	819,00	99,00	6846,00	255,0

The data presented for 10 plots show that with an increase in the dose of fertilizers, the yield of grain crops increases on average. If you build a graph, you can see that the relationship between these indicators is straightforward and can be expressed by a straight line equation:

Y x = a + bx,

Where Y– yield, c/ha;

X– amount of fertilizer applied per 1 hectare, c NPK;

A And b– parameters of the equation that need to be found.

To find the coefficient values a And b, it is necessary to solve the following system of equations:

na + bSx = Sy;

aSx + bSx 2 = Sxy,

Values ​​of å X, å y, å xy, å X 2 are calculated based on the initial data in Table 2.6. Let's substitute the obtained values ​​into the system of equations and solve it using the elimination method:

3 10A+ 30b = 255; -30A - 90b= -765;

30A + 99b =819; 30A + 99b= 819.

From here b = 6; A= 7.5. After this, the coupling equation will look like:

Y X = 7,5 + 6X.

What do these parameters represent in this equation? Coefficient A- this is a constant yield value, not related to the amount of fertilizer applied (with X=0). Coefficient b shows that with an increase in the amount of fertilizer by 1 c/ha, the yield of grain crops increases by 6 c/ha.

In addition to the connection equation, in correlation analysis the correlation coefficient is calculated, which characterizes the close relationship between the studied indicators:

Its value is close to 1. This indicates a very close, almost proportional relationship between crop yield and field fertilization. Determination coefficient ( d = r 2 = 0.92) shows that the change in yield on a given farm depends 92% on the degree of soil fertilization. It follows from this that the results of correlation analysis can be used to calculate reserves for yield growth and to determine its level for the future. Knowing, for example, that next year 4 quintals will be contributed NPK per 1 hectare of grain crops, one can expect their yield to be 31.5 c/ha ( Y x= 7.5+ 6´4) provided that the relationships between other factors do not change.

You can also install how much the yield of each crop has changed due to changes in the amount of fertilizer applied and the level of their payback. For this purpose, the change in the dose of fertilizers for crops must be multiplied by the basic level of their payback, and the change in the payback level by the actual dose of fertilizers for the reporting period.

The crop variety has a great influence on the yield.. If the proportion of more productive varieties increases, then as a result the average crop yield increases, and vice versa. The influence of this factor on changes in crop yield can be calculated using the method of chain substitution or absolute differences, as well as by the structure of crops (Table 2.12).

If you use the method of absolute differences, then the calculation is carried out in the following way: the change in the specific gravity of each variety in the total sown area of ​​the crop is multiplied by the basic yield level of the corresponding variety and the results are summed up:

The yield of agricultural crops, in addition to the listed factors, depends on a number of other agrotechnical measures: the quality and methods of tillage, placement of crops in crop rotation fields, methods and timing of crop care, the use of biological and chemical crop protection agents, liming, gypsuming of soil, etc. d. During the analysis, it is necessary to establish how the plan for all agrotechnical activities has been implemented. In case of underfulfillment of the plan for individual activities, it is necessary to find out the reasons, and, if possible, loss of production.

For this purpose, it is necessary to compare the yield in the fields where the corresponding measures were carried out and where they were not carried out (or in a different way, at a different time, in a different volume). The resulting yield difference is multiplied by the area on which it was not carried out.