METHOD AND ARRANGEMENT FOR DETERMINING THE THOUSAND-GRAIN WEIGHT OF GRAINS

Description

[0001] The present invention relates to a method and an arrangement for determining a mass- and / or size-specific size of the grains of grain fruits. State of the art

[0002] Modern precision agriculture strives to optimally utilize available resources such as water, soil, seeds, and fertilizers to maximize yield potential while minimizing resource consumption. In current technology, yield maps are generated during harvesting using suitable measuring devices and simultaneous position tracking. These maps then allow for site-specific adjustments to fertilizer quantities and seed mixes based on yield (WO 86 / 05353 A1). Further refinement of subsequent precision agriculture or plant breeding measures is achieved by measuring the constituents of the harvested crop, such as starch and protein content (EP 2 189 781 A2, KR 2016 0037507 A, EP 3 366 104 A1).

[0003] While current methods measure the yield and, where applicable, the constituents of the harvested crop on a site-specific basis, a crucial aspect remains unaccounted for when harvesting grain crops such as cereals or corn: the dimensions or mass of the individual grains, which is typically measured as the so-called thousand-grain mass (or thousand-grain weight), or the number of grains per unit area of ​​the field. The yield, already measured on a site-specific basis according to the prior art—that is, the mass of the grains (hereafter referred to as "the grain") per unit area of ​​the field—can be calculated by multiplying the number of grains per unit area by the thousand-grain mass (divided by 1000). The thousand-grain mass is usually measured by counting 1000 grains and measuring their mass (alternatively, one could multiply the volume of 1000 grains by their mass density (mass per volume)).If any two of the agronomic parameters—yield, mass (or thousand-grain mass or volume and density of individual grains), and number of grains per unit area—are known, the third agronomic parameter can be calculated. However, currently only yield measurement is planned.

[0004] Grain size, thousand-grain weight, or grain dimensions contain important information for farmers. For example, a high thousand-grain weight or relatively large grains with low yields may indicate that yields could be increased by raising the number of grains per area, as more resources are available at the location than were used by the harvested plants. Conversely, relatively low thousand-grain weights or relatively small grains indicate excessively high grain numbers per area, as fewer resources are available at the location than would be needed to allow all potentially ripening grains to actually mature.The components grain count per area and thousand-grain weight can be influenced by adjusting the seeding rate (number of plants sown per area) and spring fertilization (influencing tillering and thus the number of ears / cobs / pods per area and the number of grains per ear / cob / pod). The number of grains sown per area can be influenced by the seeding rate, as more grains sown lead to more stems per area, which in turn results in more ears / cobs / pods and therefore more grains per area. This process also works in reverse.

[0005] The tillering of the plant (referring to the stage of branching growth) can also be influenced. The number of ears formed in cereals can be affected by spring fertilization. Higher fertilization results in more tillers, while reduced fertilization leads to fewer. These tillers later develop into ears, but they also produce leaf mass, which transpires water and, if there is too much leaf mass, can cause premature ripening.

[0006] Spring fertilization also determines the number of grains per ear, cob, or pod. This mechanism can therefore also influence the number of grains per unit area, as more shoots result in more ears and thus more grains. The number of grains per unit area also affects the thousand-grain weight (the more grains, the lower the thousand-grain weight, and vice versa if water is a limiting factor). For each location, there is an optimal ratio between the number of grains per unit area and the thousand-grain weight. The yield is composed of these two components. However, so far only the yield has been measured, without knowing how the number of grains and the thousand-grain weight interact or which factor might have been limiting the yield. Therefore, no statement can yet be made about the correct seeding rate or an appropriate dosage of fertilizer applications, as the individual components of the yield cannot be determined for each specific area.

[0007] Previously, the thousand-grain mass was assumed to be constant in the combine harvester for the purpose of indicating loss or over-grain quantity (EP 1 516 522 A2, DE 34 20 800 A1) and counted if necessary before harvesting.

[0008] Furthermore, the recording of grain dimensions using a camera and image processing for yield prediction in plants growing in a field (WO 2018 / 073163 A1, WO 2018 / 073093 A1) or in the case of lost grains (EP 2 742 791 A2) as well as the optical recording of harvested grains and evaluation for the determination of the thousand-grain weight under laboratory conditions (DD 277 756 A1, DD 157 483 A1, DE 297 09 234 U1, DE 196 45 068 C1, CN 110132384 A , CN 112 304 947 A and W. Wu et al., GainTKW: A Measurement System of Thousand Kernel Weight Based on the Android Platform, Agronomy 2018, 8, 178) has been described.

[0009] Previous measurements of starch and protein content and thousand kernel weights of certain wheat varieties have not shown any significant correlation between these parameters (Dobre, PS et al, Protein content, thousand kernel weight (tkw) and volumetric mass (vm) variability in a set of wheat mutated and mutated / recombinant dh lines, AgroLife Scientific Journal, Volume 5, No. 1, 2016, pages 59-62), which also applies analogously to the relationship between protein and starch content on the one hand and density and thousand kernel weight on the other in maize (Hilliard, J. et al., Starch content, test weight, and other quality parameters of corn produced in different maturity areas of Ontario, Crop Science Vol. 14,4 (1974), pages 546 to 548). Task

[0010] Therefore, all these methods are not suitable for determining one or more of the aforementioned mass-specific quantities (thousand-grain mass, density, grain dimensions) or other information from which one or more of the aforementioned quantities could be derived in a relatively simple way.

[0011] It is an object of the present invention to provide a method and an arrangement for measuring the mass- or size-specific dimensions of grains during harvesting that are improved compared to the prior art and that enable more detailed information about the harvested crop than previously possible. Likewise, it would allow for predictions regarding the appropriate sowing rate or the correct amounts of fertilizer for spring fertilization. Solution

[0012] This problem is solved by the teachings of claims 1, 9 and 10, wherein the subordinate claims describe advantageous embodiments.

[0013] A method and arrangement for measuring the thousand-grain weight of grains of grain fruits comprise the following steps or means of carrying it out: Recording a spectrum of grains to be examined using a near-infrared spectrometer; determining the content of the grains of constituents based on the spectrum, where the constituents are water, protein and starch or correlated therewith; and deriving the thousand-grain weight based on the determined content of the grains of constituents.

[0014] In other words, the thousand-grain weight is determined using spectra of the grain fruits, which are referred to below as grains or kernels. Further details are discussed in the figure description.

[0015] In this process, the content of the grain's constituents is determined based on its spectrum, and the thousand-grain weight is calculated based on this determined content. These constituents are water, protein, and starch, or correlated with them, as is the case, for example, with protein-correlated gluten.

[0016] The mass- and / or size-specific parameters can be continuously determined during the harvesting of grain crops using a harvesting machine and recorded georeferenced on a map. However, the method and associated equipment can also be used in a mobile or stationary manner at any location. Additionally, at least one component of the harvested crop can be measured and stored georeferenced on the map along with its mass- and / or size-specific parameters. Furthermore, the yield can be measured site-specifically and stored georeferenced on the map along with its mass- and / or size-specific parameters. The map can be used for planning agronomic measures. Example of implementation

[0017] These and other tasks, features, and advantages of the present invention will become obvious to the person skilled in the art after reading the following detailed description and considering the drawings. It shows: Fig. 1 a schematic side view of a harvesting machine with a measuring arrangement for the spectroscopic investigation of a harvested crop flow, Fig. 2 an enlarged side view of the outlet area of ​​the grain elevator of the harvesting machine made of Figure 1Fig. 3 is a diagram showing the relationship between thousand grain weight (TW) and protein content for a number of measurements; Fig. 4 is a diagram showing the relationship between thousand grain weight (TW) and starch content for a number of measurements; Fig. 5 is a diagram showing the relationship between measured and spectrally determined thousand grain weights (TW); Fig. 6 is a flowchart regarding the procedure for measuring thousand grain weight; and Fig. 7 is a flowchart for evaluating the measured thousand grain weight.

[0018] The present invention relates to the determination of the thousand-grain weight (and optionally the mass density, e.g., hectoliter weight, and / or the dimensions of grains) by means of a spectroscopic measurement. In the exemplary embodiment, this measurement is carried out on a harvesting machine, which allows for mapping of the measured values. However, it would also be possible to perform a measurement with a mobile or stationary spectrometer, e.g., in a laboratory, in or on a transport vehicle, or in a grain storage facility. Harvesting machine

[0019] The Figure 1 Figure 1 shows a self-propelled agricultural harvesting machine 10 in the form of a combine harvester with a frame 12, on both sides of which are front wheels 14 engaged with the ground, which serve to propel the harvesting machine 10 in a forward direction, which in the Figure 1The harvester 10 runs to the right and is equipped with rear, steerable wheels 16. Operation of the harvester 10 is controlled from the operator's cab 18. During harvesting, a cutting unit 20 is used to harvest grain-containing crops and feed them to an inclined conveyor 22. The harvested crop is conveyed by the inclined conveyor 22 to a guide drum 24, which then feeds the crop to an axial crop processing unit 26. In the following, directional terms such as front and rear refer to the forward direction of the harvester 10.

[0020] The crop processing unit 26 comprises a rotor housing and a rotor arranged therein, to which crop processing elements are attached. Instead of an axial crop processing unit 26, a tangential threshing drum and a subsequent axial separating device or straw walkers can also be used. Grain and chaff, which fall through a concave and a separating grate, are fed to a cleaning system 28 with a blower and oscillating lamellar sieves. The cleaning system 28 removes the chaff and conveys the clean grain via a screw conveyor 30 to a clean grain elevator 32, which conveys the clean grain into a transition housing 34, from which it is conveyed by means of another screw conveyor 36 into a grain tank 38. The clean grain in the grain tank 38 can be unloaded by a discharge screw conveyor 40 onto a grain wagon, trailer, or truck.Threshed straw leaving the crop processing unit 26 is ejected through an outlet from the crop processing unit 26 and fed to a discharge drum 42, which throws the straw to the rear or feeds it to a straw chopper (not shown).

[0021] The Figure 2Figure 1 shows an enlarged view of the transition housing 34. The elevator 32 is designed as a paddle conveyor and comprises one or more chains 44 that rotate around an upper deflection wheel 46 and a lower deflection wheel 48, one of which is driven. The chain 44 carries several paddle-shaped paddles 50 that discharge the conveyed grain approximately horizontally above the upper deflection wheel 46. The transition housing 34 includes a trough 52, in which the inlet of the further screw conveyor 36 is located, and which is bounded downwards and towards the elevator 32 by a wall 54. The lateral part of the wall 54 is connected by a roof-shaped section 62 to a rear wall 56 of a housing of the elevator 32, which is enclosed at the front by a front wall 58. The front wall 58 curves at its upper side into a cover 60 of the transition housing 34.On the side opposite the outlet of the elevator 32, the transition housing 34 is bounded upwards and forwards by a concavely curved baffle plate 64 of a throughput determination device 66, against which the grain thrown from the elevator 32 impacts.

[0022] The throughput measurement device 66 further comprises a housing 68 positioned on the outside of the baffle plate 64 and the transition housing 34, which is rigidly connected to the frame 12. A plate 70 is slidably mounted in the housing 68 by guides 72 in an oblique upward and forward direction. The plate 70 is rigidly connected to the baffle plate 64 by a tube 74 and can move with the baffle plate 64 and the tube 74 relative to the housing 68. A spring 76 biases the plate 70 downward and backward, so that the plate 70 is moved upward and forward against the force of the spring 76 by grain impacting the baffle plate 64. A position sensor 78 in the form of a potentiometer detects the position of the plate 70 and thus of the impact plate 64, so that its output signal is a measure of the mass throughput of the harvested crop flow delivered by the elevator 32. spectrometer

[0023] Furthermore, in the Figure 1 and 2Spectrometers 80a and 80b are shown at two different positions. Typically, only one of the spectrometers 80a or 80b is installed. The two spectrometers 80a and 80b shown serve to illustrate different positioning options. The spectrometers 80a and 80b have an identical design, which is discussed below using spectrometer 80a as an example. Spectrometer 80a comprises a housing 82 with an opening in which a window 84 is arranged. The window of this window is preferably made of sapphire glass or another sufficiently wear-resistant material that is sufficiently transparent in the wavelength range of the light used in the investigation. Inside the housing 82 is a light source 86 that illuminates the crop flow discharged by the elevator 32 through the window 84 with broadband, so-called white light, which typically covers the near-infrared range.Light reflected from the crop flow re-enters the housing 82 through the window 84, is directed there by a lens system 88 onto a dispersive element 90 in the form of a concave mirror with a grating structure attached to its underside. This grating deflects the light in directions dependent on the wavelength and finally reaches a detector 92 with an array of light-sensitive elements that emit signals dependent on the intensity of the received light. The method described here is only one possible embodiment of a spectrometer arrangement for measuring constituents in agricultural products. It is also possible to position the light source opposite the window 84 so that light illuminating the crop strikes the lens system. Measurements can also be performed in a spherical arrangement (see WO 2019 / 14997 A1). The dispersive element can also be designed differently, e.g.The detector 92 can be a transmission grating or a MEMS. An evaluation unit 94 connected to the detector 92 evaluates the output signals of the detector 92 and provides spectra and / or information derived therefrom, e.g., proportions of constituents in the crop stream. Suitable spectrometers are described in DE 199 22 867 A1 and DE 10 2004 048 103 A1, the disclosures of which are incorporated into the present documents by reference.

[0024] The spectrometer 80a is arranged above the cover 60 of the transition housing 34, with the window 84 located within an opening in a ramp 96, which is positioned directly upstream of the baffle plate 64. The ramp 96 serves to direct the crop flow discharged from the elevator 32 onto the baffle plate 64 and, in particular, to prevent grain from being undesirably discharged onto the outer edge of the baffle plate 64 at the leading edge relative to the crop flow. Thanks to the relatively small angle of the ramp 96 and the window 84, which can be, for example, between 3 and 5°, the mass flow of the crop provides a self-cleaning function for the glazing or pane of the window 84 of the spectrometer 80a. This prevents soiling or the accumulation of deposits of crop residue or other dirt particles on the pane of the window 84.

[0025] Spectrometer 80b, on the other hand, is arranged at the downstream end of the baffle plate 64, with window 84 extending obliquely downwards and backwards towards the center of the trough 52. The windows 84 of both spectrometers 80a and 80b are surrounded by the flow of harvested material, so that any impurities are carried away and do not adhere to the windows 84.

[0026] The evaluation unit 94 of the spectrometer 80a or 80b and the position sensor 78 of the throughput determination unit 66 are connected via a bus system or an associated cable or via radio or optically to a recording unit 98, which is located in the operator cabin 18, cf. Figure 1The recording device 98 is further connected to a positioning device 100 in the form of an antenna and receiving equipment for receiving and processing signals from a satellite-based positioning system, e.g., GPS and / or GLONASS and / or Eureka. The signals from the evaluation unit 94 of the spectrometer 80a or 80b and the position sensor 78 of the throughput measurement device 66 are thus georeferenced and recorded by the recording device 98 so that they can later be used for billing purposes or for use in precision agriculture. These signals can also be used for the automatic adjustment of components of the harvesting machine 10, for example, to adjust the fan speed and sieve opening width of the cleaning system 28 or the speed of the axial crop processing unit 26.Mounting the spectrometer(s) 80a and / or 80b and the throughput measurement device 66 in close proximity has the advantage that measurements of the same crop are recorded, meaning that the temporal correlation of the measurements is very good. However, it would also be possible to mount the spectrometer 80a or 80b at any other location on the harvesting machine 10, for example on the elevator 32 or a separate measuring chamber that can be filled by the elevator 32 (see CA 2 182 989 C or EP 1 305 994 A1) or on the screw conveyor 30. Analysis of the spectra

[0027] The object of the present invention is to determine a mass- and / or size-specific dimension of the harvested grain, for example, its thousand-grain weight, mass density, and / or dimensions. The size (dimensions, i.e., length and / or diameter and / or volume) of the grains and the mass measured in kg or g, or the weight of the individual grains measured in N (Newtons), varies not only depending on the type of crop but also on the specific location, because the grains become larger or smaller depending on the supply of water, light, soil properties, plant density, fertilization, etc. Furthermore, depending on local conditions, more or fewer plants grow, producing more or fewer grains. This also affects the yield, which can be calculated by multiplying the number of grains per unit area by their respective mass.For agronomic purposes, it is therefore useful to obtain a map showing a quantity dependent on the mass and / or size of the grains, based on which subsequent measures can be planned for specific locations. The quantity in question is, in particular, the thousand-grain weight, which is a commonly used agronomically.

[0028] In the prior art, the measurement of constituents (protein and starch content) in grain is already known and established. Near-infrared spectroscopy is typically used for this purpose. The relative moisture, starch, or protein content (as a percentage) in the dry or total mass of a sample is measured. Calibration data is stored in the evaluation unit 94 of the spectrometer 80a and / or 80b, based on which the measured spectra are converted into the aforementioned constituent content. This evaluation (also with regard to the other agronomic data discussed below) can also be performed in the recording unit 98 or on any other computer on the harvester 10 or on a remote computer to which the spectra are wirelessly transmitted, or the spectra can first be recorded (especially georeferenced) and later evaluated on any computer.

[0029] Since grain weight is a structural parameter and not a chemical quantity, it cannot prima facie be assumed that the thousand-grain weight or a related agronomic quantity (in particular the mass density or hectoliter weight of the grain or its dimensions) could be measured using a near-infrared spectrometer (cf. the measurements by Dobre et al. and Hilliard et al., ibid.).

[0030] Closer examination, however, reveals a surprising fact: due to the physiology of plant growth, it is still possible to estimate grain weight based on its constituent values, and thus grain weight can be determined, at least approximately, using constituent sensors. This is because, for example, wheat grains form inner protein nuclei of similar size. The starch body grows around these protein nuclei, and its final size depends on the nutritional status of the individual plant. For this reason, a heavy and large grain typically has a high starch-to-protein ratio, while a light and small grain has a low starch-to-protein ratio.

[0031] In this regard, reference should be made to the Figures 3 and 4References are made to data showing protein content, starch content, and thousand-grain weight (TW) for various samples. The different points represent a reference measurement (i.e., a set of measurements for a specific wheat variety used to establish calibration data), new data for the same variety (determined later), data from durum wheat, and some measurements from Dobre et al., op. cit. It is evident that certain correlations can be observed when measuring within a variety or even within similar grain types. For example, the thousand-grain weight decreases with increasing protein content, while it increases with increasing starch content. Different coefficients would be appropriate for the evaluation of the measurements for durum wheat and those from Dobre et al.

[0032] Using mathematical methods, a suitable equation was created based on the reference measurement, with which the thousand grain weight (TKW) can be modeled: TKW ∼ c 0 + c 1 * Stärke % / Protein % + c 2 * Feuchte % / Protein % * 1 − Feuchte % / 100

[0033] A corresponding curve is in the Figure 5 The graph shows a comparison of thousand-grain weights measured using equation (1) and those calculated using equation (1). The coefficients c0, c1, and c2 used for this comparison were determined using the reference material and applied to samples of the same grain variety (new data). A usable correlation was found between the reference measurement and the new data. Therefore, it is possible to determine the thousand-grain weight using the spectra measured with spectrometer 80a or 80b. Durum wheat is a different variety, as is the grain investigated in the paper by Dobre et al. The plot shows that the coefficients c0, c1, and c2 are unsuitable for durum wheat, and appropriate, adjusted coefficients still need to be determined.

[0034] The protein and starch content are determined by the ingredient sensor (spectrometer 80a, 80b) with respect to the dry mass, and the moisture content is determined with respect to the total mass. The constants c0, c1, and c2 can be determined for each grain variety under investigation through calibration measurements. They differ for different varieties, and it may be necessary to use different equations for other varieties or types of grain.

[0035] The relationship between the thousand grain weight and constituents can, instead of using equation (1), also be modeled or learned by more general functions such as neural networks, or the thousand grain weight could be determined directly from the NIR spectra (analogous to the previous procedure for determining constituents from the spectra by generating calibration data).

[0036] One possible approach for measuring and mapping the thousand-grain weight is described in the Figure 6As shown. After starting in step 101, in step 102 the parameters for the respective harvested crop (grain breeding) are loaded into a memory of the evaluation unit 94. The parameters include calibration data for converting the spectra into moisture, protein, and starch content, and the constants c0, c1, and c2 from equation (1). In step 104, one or more spectra are recorded. In step 106, the moisture, protein, and starch content are determined based on the spectrum or spectra and the calibration data. In step 108, the thousand-grain weight (TWW) is determined using equation (1). In step 110, the nutrient content and the thousand-grain weight are plotted on a map using position signals from the positioning unit 100. Step 110 is followed again by step 104, unless the process is completed when the field is harvested.The determination and mapping of thousand-grain weight can also be carried out subsequently, e.g., in a farm management information system. Protein, starch, and moisture (or their spectra) can be mapped and later analyzed.

[0037] In step 108, the determined thousand-grain weight can be referenced to the location where the grains grew in a manner known per se, cf. EP 3 008 990 A2, i.e., the travel time of the harvested crop between harvesting and sensing and the distance traveled by the harvesting machine 10 or position determination device 100 in the meantime can be compensated.

[0038] Furthermore, the yield (in volume or mass per unit area) can be measured and mapped using the throughput determination device 66 (see also EP 3 901 588 A1 and the prior art cited therein), and the mass density (hectoliter weight, etc.) of the grain can be calculated based on the yield and the thousand-grain weight. Alternatively or additionally, the number of grains per unit area of ​​the field can be determined based on the yield and the thousand-grain weight. Reference is made to the earlier patent application DE 10 2022 110 185.1, the disclosure of which is incorporated into these documents by reference.

[0039] The thousand-grain weight is also correlated with the density (hectoliter weight), so the latter could also be determined using a modified model based on the spectra or constituents. Similarly, due to the relationships between constituents and grain dimensions discussed above, the spectra also contain information about the dimensions. These can therefore be determined from the spectra, analogous to the procedure for the thousand-grain weight, either indirectly via the constituents or directly from the spectra using appropriate calibration data. Further uses of the thousand-grain weight

[0040] According to the procedure of Figure 6The generated map can be transmitted via data transmission or portable storage device to a farmer's or agronomist's stationary or mobile computer and used for planning agronomic measures. These measures can be planned based on grain mass and / or the number of grains per unit area and / or their dimensions (which can be calculated based on other parameters and yield, or, in the case of dimensions, determined directly from spectra, as described in the previous paragraph). In particular, seeding rates can be planned based on the number of grains per unit area and / or their dimensions and / or their mass.

[0041] The Figure 7 shows a possible approach to using the procedures according to Figure 6generated map. After starting in step 120, in step 122 the map is called up on any computer, i.e., loaded into its memory. The computer can be a desktop computer located in the office of the farmer or a contracted agronomist, whose field is being harvested with harvester 10 according to the procedure of Figure 6The map can be displayed two-dimensionally on a display device in step 122, where different thousand-grain weights (or any other quantity representative of the dimensions, mass, or weight of the grains or their number per unit area) are indicated by colors or other means (grayscale, hatching, etc.). The map can also include one or more nutrient contents of the harvested crop, measured and mapped using the near-infrared sensor 80a, 80b. These one or more nutrient contents, e.g., the protein content of the harvested crop, can also be displayed. Similarly, one or more other field properties, e.g.,The soil type or site-specific varying or constant fertilizer applications across the field, or measured nutrients in the soil, or the yield (in grains or mass per area), or the number of plants sown per unit area, can be used as a basis for calculation.

[0042] In step 124, yield-limiting factors can be identified and displayed using the aforementioned map and, in particular, the site-specific recorded thousand-grain weights or one or more other parameters representative of the dimensions, mass, or weight of the grains or their number per unit area. Furthermore, the (in the procedure according to Figure 6 The yield per unit area, also measured and recorded on a site-specific basis with the throughput determination device 66, is displayed and / or used to calculate the number of grains per unit area based on the thousand grain masses.

[0043] Documenting the (thousand-) grain mass and / or grain volume makes it possible to define the composition of the yield at each location within the field. A given yield can thus be based on a larger number of smaller grains per area or a smaller number of larger grains per area. To further clarify this, the number of grains per area can be calculated by dividing the yield, also mapped at specific locations and measured in units of mass per area (e.g., by the throughput measurement device 66 in the grain elevator 32), by the mapped (thousand-) grain mass.

[0044] The calculated number of grains per unit area and / or their dimensions or mass can provide insights into whether potential yields have been wasted in plant cultivation. For example, a small number of large grains indicates potential for a higher yield. In this case, the seeding rate could be increased, or tillering could be influenced by sufficient spring fertilization, meaning more plants per unit area should be cultivated in the future. Conversely, a large number of small grains (shriveled grains) indicates insufficient water and / or nutrients to support the number of plants cultivated per unit area. In this case, the seeding rate should be reduced and / or the fertilization and, if necessary, the water supply adjusted.To easily identify such relationships, a map can be displayed showing the thousand-grain weight divided by the number of grains per unit area (or its reciprocal). High values ​​for thousand-grain weight divided by the number of grains per unit area would indicate an increase in seeding rate / strengthening of tillering, while low values ​​would indicate a decrease.

[0045] The described recording and mapping of the thousand-grain mass and / or dimensions of the grains and / or number of grains per unit area thus helps the farmer or agronomist to adapt crop production measures to changing soils and conditions.

[0046] In step 124, a map showing the limiting factors can be created. This map can display, for specific locations, which agronomic measures were lacking or could be improved. In particular, missing or excess fertilizer can be determined based on protein content, missing or excess water based on grain size, and excessive sowing or tillering based on thousand-grain weight and the number of grains per area.

[0047] In step 126, a new fertilization and sowing map is created, incorporating the conclusions drawn in step 124. Based on the displayed data, the farmer or commissioned agronomist can then determine which measures are appropriate at which locations, whether qualitative or quantitative. Alternatively, a computer-aided algorithm can be used, particularly one that is self-learning, meaning it gradually learns, based on previous measures and their measured effects, which measures are most effective for the field in question.

[0048] The map created in the described manner, showing the site-specific measures to be implemented, is taken into account in step 128 during a subsequent measure, particularly in the following cultivation cycle.

[0049] After all this, it is evident that the site-specifically recorded and mapped grain weights can be determined using the signals from spectrometers 80a and 80b, and that, by including the yield data, further agronomic parameters can be determined (number of grains per unit area and mass density, which can also be measured using the spectra). These agronomic parameters form a useful basis for planning subsequent measures, in particular the site-specific seeding rate and an adapted spring fertilization, in order to sufficiently influence the number of grains per area and the thousand-grain weight and achieve the yield target. As explained above, these parameters can be determined from any selection of the following measured and mapped values: yield, grain dimensions (or mass), and number of grains per unit area.

Claims

1. Method for measuring the thousand kernel weight of grains of grain crops, comprising the following steps: recording a spectrum of the grains to be studied by means of a spectrometer (80a, 80b) operating in the near-infrared range, determining the contents of ingredients of the studied grains on the basis of the spectrum, wherein the ingredients are water, protein and starch or are correlated therewith; and deriving the thousand kernel weight of the studied grains on the basis of the determined contents of ingredients of the studied grains.

2. Method according to Claim 1, wherein the thousand kernel weight is determined continuously during harvesting of the grains by means of a harvester (10) on a different crop in each case and is recorded georeferenced in a map.

3. Method according to Claim 2, wherein the determined contents of ingredients are stored georeferenced in the map together with the thousand kernel weight.

4. Method according to Claim 2 or 3, wherein the yield is additionally measured subarea-specifically and is stored georeferenced in the map together with the thousand kernel weight, the map being usable for planning agronomic measures.

5. Arrangement for measuring the thousand kernel weight of grains of grain crops, comprising: a spectrometer (80a, 80b) operating in the near-infrared range, which is configured to record a spectrum of grains of the grain crops to be studied, and an evaluation device (94), which is configured: to determine the contents of ingredients of the studied grains on the basis of the spectrum, wherein the ingredients are water, protein and starch or are correlated therewith; and to derive the thousand kernel weight on the basis of the determined contents of the ingredients of the grains.

6. Harvester (10) comprising an arrangement according to Claim 5.