Crop mixtures are often beneficial in crop rotations to enhance resource utilization and yield stability. While targeted management, dependent on the local species composition, has the potential to ...increase the crop value, it comes at a higher expense in terms of field surveys. As fine-grained species distribution mapping of within-field variation is typically unfeasible, the potential of targeted management remains an open research area. In this work, we propose a new method for determining the biomass species composition from high resolution color images using a DeepLabv3+ based convolutional neural network. Data collection has been performed at four separate experimental plot trial sites over three growing seasons. The method is thoroughly evaluated by predicting the biomass composition of different grass clover mixtures using only an image of the canopy. With a relative biomass clover content prediction of R
= 0.91, we present new state-of-the-art results across the largely varying sites. Combining the algorithm with an all terrain vehicle (ATV)-mounted image acquisition system, we demonstrate a feasible method for robust coverage and species distribution mapping of 225 ha of mixed crops at a median capacity of 17 ha per hour at 173 images per hectare.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This article presents the data obtained from a field experiment in which grass–clover leys were fertilized with increasing N rates applied in either mineral N fertilizer and/or cattle slurry forms. ...The leys were composed of a 2–species mixture of white clover (Trifolium repens L.) and ryegrass (Lolium perenne L.) and a 4–species mixture of white clover, red clover (Trifolium pratense L.), festulolium (Festulolium braunii) and ryegrass. In total, eighty fields were established at two farm sites in the western part of Denmark on sandy soils and monitored for two herbage seasons (2018–2019). Dry matter yield, botanical composition, N concentration and the proportion of N derived from the atmosphere using the 15 N dilution method were recorded in the harvestable biomass after each cut. Furthermore, the specific growth, N uptake and quantitative biological N fixation of the species were determined.
The dataset can be used to establish the N balance, to calculate the optimal economic fertilization rate based on grass-clover composition and to predict N leaching and residual effect.
The data presented were thoroughly used and discussed in the research article “Contrasting effects of slurry and mineral fertilizer on N2 fixation in grass-clover mixtures”.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In dairy systems, grass–clover swards are fertilized with on–farm cattle slurry as a basic dressing and often supplemented with mineral fertilizer throughout the season. Uncertainty remains on ...consequences for N input from atmospheric N2-fixation by grassland legumes. The aim of this study was to examine the N response of slurry versus mineral N fertilization on clover dynamics, the proportion of N derived from the atmosphere (%Ndfa) and the quantitative N2-fixation (qBNF) using the 15N isotope dilution method. This was done in an on farm setting at two sites in two years with increasing rates of N fertilizer (0–480 kg available N ha-1) either of mineral N only or combined with application of cattle slurry. The leys were at one site composed a 2–species mixture of white clover (Trifolium repens L.) and ryegrass (Lolium perenne L.) and at the other site of a 4–species mixture of white clover, red clover (Trifolium pretense L.), festulolium (Festulolium braunii) and ryegrass. Species dynamics were significantly affected by fertilizer rate in the 2–species sward and by fertilizer rate and type in the 4–species sward. Reduction of the clover proportion in response to fertilization was due to a clover yield decrease (2–species sward) or a grass yield increase (4–species sward). In the 4–species sward, in treatments with mineral N only %Ndfa decreased markedly with N rate, whereas the corresponding slurry + mineral N treatments did not. Thus, apart from fertilization with mineral N only at one site the general picture was a relatively high (>80%) %Ndfa over the season when the N level was below 200–300 kg available N ha-1. The qBNF of the harvested biomass in sward without fertilization reached 193–216 kg N ha-1 in the 2–species sward and 203–286 kg N ha-1 in the 4–species sward. Clover persisted at high fertilization rates, but qBNF was reduced to 16–79 kg N ha-1 and 58–163 kg N ha-1 in 2– and 4–species swards, respectively. Interestingly, in the 4–species sward amended with slurry + mineral N, qBNF was high and independent of fertilization rate. We conclude that response of clover dynamics to N fertilization differed with fertilizer type and level – slurry have lower effect whereas the effect of mineral N only on N2-fixation is less predictable.
•N response of grass–clover leys was investigated as affected by mineral N or slurry.•Dry matter yield and grass fraction increased as expected with N level.•Leys at two sites showed two patterns of N2-fixation activity response to fertilizer type.•Slurry in combination with mineral N sustained high N2-fixation until 240 kg N ha-1.•Clover N2-fixation response to mineral N only was less predictable among sites.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Genotypic differences in root Mn uptake, root-to-shoot Mn translocation and photosynthetic responses to Mn deficiency are observed in maize.•The metal transport genes are differentially expressed in ...the roots of contrasting genotypes with different tolerance to low-Mn.•Time-course of changes in Fv/Fm values in response to Mn deficiency provides a useful screening index for low-Mn tolerance.
Deficiency of manganese (Mn) is a serious problem reducing crop yields on calcareous and sandy soils throughout the world. In maize, limited knowledge is available on genotypic differences in tolerance to low-Mn supply and the physiological mechanisms underlying this tolerance. In the present study we have evaluated twelve maize genotypes (inbred lines) for their tolerance to Mn deficiency. The evaluation was based on measurements of how low-Mn supply affected shoot biomass, leaf Mn concentrations, maximum quantum efficiency of photosystem II (Fv/Fm), photosynthetic net CO2 assimilation, root length, Mn uptake and root-shoot Mn translocation. Tolerant genotypes were able to maintain optimum Fv/Fm values under a longer period of Mn deficiency with less reduction of foliar Mn concentration and photosynthetic rate, resulting in less reduction of shoot biomass, compared to sensitive genotypes. Efficient root uptake of Mn and root-to-shoot translocation of Mn also contributed to improved tolerance to Mn-deficiency. The metal transport genes YSL, NRAMP, ZIP, CAX and MTP, involved in root Mn uptake, root-to-shoot Mn translocation and vacuolar Mn homeostasis, were more highly expressed in the efficient genotype K22compared to sensitive genotype BY815. With respect to breeding of maize cultivars with improved Mn-efficiency, the time-course of changes in Fv/Fm values in response to Mn-deficiency provides a useful screening index for low-Mn tolerance.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article presents the data obtained from a field experiment in which grass-clover leys were fertilized with increasing N rates applied in either mineral N fertilizer and/or cattle slurry forms. ...The leys were composed of a 2-species mixture of white clover (
.) and ryegrass (
.) and a 4-species mixture of white clover, red clover (
.), festulolium (
) and ryegrass. In total, eighty fields were established at two farm sites in the western part of Denmark on sandy soils and monitored for two herbage seasons (2018-2019). Dry matter yield, botanical composition, N concentration and the proportion of N derived from the atmosphere using the 15 N dilution method were recorded in the harvestable biomass after each cut. Furthermore, the specific growth, N uptake and quantitative biological N fixation of the species were determined. The dataset can be used to establish the N balance, to calculate the optimal economic fertilization rate based on grass-clover composition and to predict N leaching and residual effect. The data presented were thoroughly used and discussed in the research article "Contrasting effects of slurry and mineral fertilizer on N
fixation in grass-clover mixtures".
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Load filters
No result was selected!
Please select the results that you wish to export.
The search was successfully saved.
Editing
The search could not be saved.
Saved searches can be viewed in the list My searches.
The changes made to the saved search were saved successfully.
Save search
Shelf entry
No result was selected!
Adding material to shelf was successful.
Adding material to shelf was partly successful.
Adding material to shelf failed completely.
It was not necessary to add the material to the shelf.
Please select the results that you want to put on shelf!
On shelf the following records have been successfully added:
On shelf the following records have been successfully added:
PDF
