Browsing by Subject "Ertrag"

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Eco-physiological studies on False Horn plantain
(2020) Dzomeku, Beloved Mensah; Wünsche, Jens Norbert
West Africa suffers from climate uncertainty, high levels of variability, lack of access to real-time and future climate information, and poor predictive capacity are common barriers to adaptation though the region is identified as climate-change hotspot. The regions vulnerability is heightened by its overdependence on rain-fed agriculture, with its sensitivity to climate change and variability. Rain-fed agriculture contributes 30% of GDP and employs about 70% of the population, and it is the main safety net of the rural poor. Drought affects plantain production in West Africa resulting in high level of food insecurity among the vulnerable. Under rain-fed production, achievable yield of plantain landraces are 11.0t/ha while the potential yield is 20t/ha. Plantain breeding is limited due to the complex nature of the breeding process. Plantain plant itself is a giant herbaceous plant occupying 6m2 of land hence only 1667 could occupy a hectare of land. The production system is faced with a myriad of challenges from inadequate healthy planting materials at the time of plantain through the production system to post-harvest. Unlike bananas which are mainly produce by multinational companies under irrigation, plantain production is mainly by smallholder farmers under rain-fed agriculture. Whereas banana production under irrigation is efficient, plantain production under rainfed production is haphazard and unsustainable. Farm sizes range between 0.4 to 5ha. Major limiting factors of the rainfed system is drought resulting in low yields and economic loses. Our study seeks to understand the effects of drought on the physiological responses of plantain crop under rainfed production. Different experiments were conducted to study the responses of various cultivars to on-farm rapid production of healthy planting materials. The results revealed that drought seriously affects natural regeneration of plantain planting materials as such new approaches need to be used for sufficient production. As each plantain plant produces averagely 42 leaves before flowering and each leaf has at least one axillary bud, it presupposes that 42 suckers should be produced at harvest. However, at harvest only 12 healthy suckers are produced around each plantain plant. The approach is able to exploit the full potential of every sucker to generate healthy planting materials. This technique therefore could be used to set up commercial propagation system for plantain planting material production. The study revealed Apantu and hybrid plantain FHIA-21 to show same responses. Plantain farmers can easily produce in large quantities healthy plantain planting materials using sawdust and building their own humidity chambers near water source. The study also showed that there is the potential for farmers to use this technique for establishing commercial propagation centres to generate healthy planting materials. We also studied the physiological responses of Apantu crop to water regimes and natural mycorrhization of plantains. Also, study was conducted on the fruit maturity index and the effect of climate variability on fruit micronutrient content. The natural mycorrhization of plantain roots was the first to be reported on plantain in Ghana. During the study it was observed that plantain roots were naturally colonised by mycorrhizae. However, this phenomenon was cultivar specific; with Apantu roots more colonised compared to Apem. Sustainable intensification of plantain production could be achieved through the use of beneficial soil microbes in production. Conventional production systems, however, do not promote the survival of these microbes. The study further revealed that plantains respond to water stress by reduction in stomatal density, movement and reduction in leaf area. In addition, early stages of water stress had little effect on the final yield of the crop. The anatomical and physiological studies were challenges faced in laticiferous plant like the plantain. However, drought stress at advance stage of growth of plantain adversely affect yields. Our study also showed that fruit maturity index could vary with seasons. The various maturity indices used in plantain production could not be used under rain-fed conditions; especially angularity. The angularity index used was observed not to be appropriate in the dry season. The study also revealed high α-carotene levels with seasonality and maturity in plantain. The high levels of provitamin A in plantain fruits during the dry season coincided with high incidence of sun’s UV index. This finding could play a significant role in the plantain industry as a food security crop the vulnerable who could not afford the high provitamin A foods especially for children under five years. However, the retention and bioavailability of the carotenoid after cooking need to be studied. In conclusion all the chapters showed clear understanding of the behaviour of plantain under severe adverse environmental conditions and conclusions drawn to guide future production of the crop. Under climate change with its complexities, further studies on plantain is needed to improve productivity to achieve food security in West Africa.
Effects of weeds on yield and determination of economic thresholds for site-specific weed control using sensor technology
(2014) Keller, Martina; Gerhards, Roland
Weeds can cause high yield losses. Knowledge about the weeds occurring, their distribution within fields and their effects on the crop yield is important to achieve effective weed control. The critical period for weed control (CPWC) and the economic threshold (ET) are important key concepts and management tools in weed control. While the former helps to time weed control in crops of low competitiveness, the latter provides a decision aid to determine whether weed control is necessary. This decision is generally taken at the field level. Weeds have been found to be distributed heterogeneously within fields. Site-specific weed control (SSWC) addresses this sub-field variation by determining weed distribution as input, by taking control decisions in the decision component and by providing control measures as output at high spatial resolution. Sensor systems for automated weed recognition were identified as prerequisite for SSWC since costs for scouting are too high. While experiences with SSWC using sensor data as input are still scarce, studies showed that considerable herbicide savings could be achieved with SSWC. ETs can serve as thresholds for the decision component in SSWC systems. However, the commonly used ETs were suggested decades ago and have not been updated to changing conditions since. The same is the case for the CPWC in maize in Germany. In addition, the approaches to determine the CPWC are usually not based on economic considerations, which are highly relevant to farmers. Thus, the objectives of this thesis are: 1. To test different models and to provide a straightforward approach to integrate economical aspects in the concept of the CPWC for two weed control strategies: Herbicide based (Germany) and hoeing based (Benin); 2. To determine the effect of weeds on yield and to calculate ETs under current conditions which can be used for SSWC; 3. To evaluate the use of bi-spectral cameras and shape-based classification algorithms for weed detection in SSWC; and 4. To determine changes in weed frequencies, herbicide use and yield over the last 20 years in southwestern Germany. Datasets in maize from Germany and Benin served as input for the CPWC analyses. The log-logistic model was found to provide a similar fit as the commonly used models but its parameters are biologically meaningful. For Germany, analyses using a full cost model revealed that farmers should aim at applying herbicides early before the 4-leaf stage of maize. In Benin, where weed control is mainly done by hoeing, analyses showed that one well- timed weeding operation around the 10-leaf stage could already be cost-effective. A second weeding operation at a later stage would assure profit. The precision experimental design (PED) was employed to determine the effect of weeds, soil properties and herbicides on crop yield in three winter wheat trials. In this design, large field trials’ geodata of weed distribution, herbicide application, soil properties and yield are used to model the effects of the former three on yield. Galium aparine, other broadleaved weeds and Alopecurus myosuroides reduced yield by 17.5, 1.2 and 12.4 kg ha-1 plant-1 m2 determined by weed counts. The determined thresholds for SSWC with independently applied herbicides were 4, 48 and 12 plants m-2, respectively. Bi-spectral camera based weed–yield estimates were difficult to interpret showing that this technology still needs to be improved. However, large weed patches were correctly identified. ETs derived of field trials’ data carried out at several sites over 13 years in the framework of the ’Gemeinschaftsversuche Baden-Württemberg’ were 9.2-9.8 and 4.5-8.9 % absolute weed coverage for winter wheat and winter barley and 3.7% to 5.5% relative weed coverage for maize. Overall, the weed frequencies in winter cereals were found to be more stable than the weed frequencies in maize during the observation period. In maize, a frequency increase of thermophilic species was found. Trends of considerable yield increases of 0.16, 0.08 and 0.2 t ha-1 for winter wheat, winter barely and maize, respectively, were estimated if weeds were successfully controlled. In order to evaluate the use of bi-spectral cameras and shapebased classification algorithms for weed detection in SSWC, herbicides were applied site-specifically using weed densities determined by bi-spectral camera technology in a winter wheat and maize field. Threshold values were employed for decision taking. Using this approach herbicide savings between 58 and 83 % could be achieved. Such reductions in herbicide use would meet the demand of society to minimize the release of plant protection products in the environment. Misclassification occurred if weeds overlapped with crop plants and crop leaf tips were frequently misclassified as grass weeds. Improvements in equipment, especially between the interfaces of camera, classification algorithms, decision component and sprayer are advisable for further trials. In conclusion, the derived ETs can be easily implemented in a straightforward SSWC system or can serve as decision aid for farmers in winter wheat and winter barley. Further model testing and adjusting would be necessary. For maize, the use of ETs at the field level is not suggested by this study, however the need for early weed control is clearly demonstrated. Bi-spectral camera technology combined with classification algorithms to detect weeds is promising for research use and for SSWC, but still requires some technical improvements.
Fertilizer placement and the potential for its combination with bio-effectors to improve crop nutrient acquisition and yield
(2016) Nkebiwe, Peteh Mehdi; Müller, Torsten
Even when total nitrogen (N) and phosphorus (P) concentrations in most agricultural soils are high, the concentrations of plant-available N and P fractions are often inadequate for acceptable yield. In comparison to conventional fertilizer application by homogenous broadcast over the soil surface (with or without subsequent incorporation), fertilizer placement in defined soil areas/volumes close to seeds or crop roots is a more effective application method to enhance the plant-availability of applied fertilizers. Nevertheless, considerable root growth in subsurface nutrient patches or around concentrated fertilizer-depots (and/or improved nutrient influx rates in roots) is a prerequisite for improved uptake of placed nutrients. Furthermore, zones with intense rooting around placed fertilizer depots (“rhizosphere hotspots”) with high concentrations of organic nutrients released as root exudates may be favorable for the survival and establishment of inoculated plant-growth-promoting microorganisms (PGPMs), which mobilize nutrients in soil to favor plant growth. In the last three decades, several published field studies comparing fertilizer placement to fertilizer broadcast arrived at different and often conflicting results regarding their effects on yield and nutrient status of various crops. For this reason, the first task was to conduct a Meta-analysis on data in published peer-reviewed field studies on fertilizer placement that met a set of pre-defined criteria for inclusion. We investigated the relative effect of fertilizer placement for specific fertilizer formulations (e.g. NH4+ and CO(NH2)2 without or in combination with soluble P (HPO42-; H2PO4-); soluble K; solid or liquid manure) in a precise restricted area on surface or subsurface soil in comparison to fertilizer broadcast on yield, nutrient concentration and content in above-ground plant parts. We utilized data from a total of 40 field studies published between 1982 and 2015 (85% of studies published from 2000) that met our criteria. We used the method of “baseline contrasts” to compare different fertilizer placement treatments to fertilizer broadcast as a common control or baseline treatment. Results showed that overall, fertilizer placement led to +3.7% higher yields, +3.7% higher concentrations of nutrients in above-ground plant parts and +11.9% higher contents of nutrients also in above-ground plant parts than fertilizer broadcast application. Placement depth had a strong effect of the outcome of fertilizer placement because relative placement effects increased with increasing fertilizer placement depth. Composition of fertilizer formulations was also an important factor. High yields of fertilizer placement relative to fertilizer broadcast application were obtained for CO(NH2)2 in combination with soluble P (HPO42-; H2PO4-) (+27%) or NH4+ in combination with HPO42-; H2PO4- (+15%) (Nkebiwe et al., 2016 a: Field Crops Research 196: 389–401). The next aim was to investigate the effect of fertilizer placement in subsurface soil in combination with application of bio-effectors (BEs) (PGPMs and natural active substances such as humic acids and seaweed extracts) on root growth of crop plants, establishment of inoculated PGPM in the rhizosphere, grain and biomass production as well as plant nutrient status for maize (Zea mays L) and wheat (Triticum aestivum L) cultures. Through various pot and rhizobox experiments, we observed that placement of a subsurface concentrated NH4+-fertilizer depot stabilized with the nitrification inhibitor DMPP (3,4-di-methylpyrazolphosphate) induced dense rooting around the depot contributing to more efficient exploitation of the depot. For this, it was crucial the N persisted in the depot mainly as poorly mobile NH4+, in order to induce localized depot-zone root-growth as well as favorable chemical and biological changes in the rhizosphere to improve N and P uptake by crop plants. Through in vitro culture experiments on solid and liquid media, we could show that via acidification of the growth media, several selected microbial BEs were capable to solubilize sparingly soluble inorganic phosphates and also that these BEs showed considerable tolerance to high concentrations of NH4+ und DMPP. The latter indicated a potential for the BEs to colonize plant roots in NH4+-rich well rooted soil zones around a subsurface NH4+-fertilizer depot (Nkebiwe et al., 2016 c: Manuscript submitted). Through further pot experiments and four others experiments as Bachelor and Master theses conduction under my supervision, we observed that certain BEs that readily solubilized tri-calcium phosphates in vitro were able to mobilize rock phosphate (RP) applied in soil-based substrates when N was supplied as stabilized NH4++DMPP, thereby contributing to enhanced P uptake and growth of maize and wheat plants. The bacterial BE Pseudomonas sp. DSMZ 13134 and BE consortia products containing bacteria and fungi such as CombiFectorA were good candidates. BE-induced RP-solubilzation occurred mainly in substrates with low CaCO3 contents indicating low P sorption capacity for neutral and moderately alkaline soils. With CombiFectorA, maize P-acquisition from sewage sludge ash could be enhanced, thus increasing the efficiency of a sparingly soluble fertilizer based of recycled wastes. Possible explanations for the beneficial effects of best performing BEs to improve plant growth were enhanced solubility of sparingly soluble P fertilizers via acidification of the rhizosphere and release of nutrient-chelating substances as well as improvement of root growth for better spatial interception of nutrients (Nkebiwe et al., 2016 d: Manuscript in preparation). Alongside, more greenhouse and two field experiments (grain maize 2014 and maize silage 2015) were designed, planned, conducted and evaluated. A peer-reviewed paper from this work has already been published (Nkebiwe et al., 2016 b: Chemical and Biological Technologies in Agriculture 3:15). In the greenhouse and experiments, placement of a concentrated stabilized NH4+-fertilizer depot led to improved root and shoot growth, and increased shoot N and P contents. Through intense root growth of maize around the NH4+-depot, increased root-colonization by Pseudomonas sp. DSMZ 13134 close to seeds could be observed. In the field, many weeks after subsurface placement of the concentrated stabilized NH4+-depot, it could be shown that N considerably persisted in the depot-zone as NH4+, which strongly induced depot-zone root growth. Placement of the NH4+-depot led to +7.4 % increase in grain yield of maize (2014) and +5.8% increase in maize silage yield (2015) in comparison to fertilizer broadcast. Placement of Pseudomonas sp. DSMZ 13134 inoculum in the sowing row let to +7.1% increase in yield of maize silage (2015) in comparison to the non-inoculated control. In total, these results showed that precise placement of specific fertilizer formulations in combination with the application of selected PGPMs can lead to improved plant growth, improved N and P uptake with a potential to save resources.
Genome-wide prediction of testcross performance and phenotypic stability for important agronomic and quality traits in elite hybrid rye (Secale cereale L.)
(2016) Wang, Yu; Miedaner, Thomas
Genomic selection offers a greater potential for improving complex, quantitative traits in winter rye than marker-assisted selection. Prediction accuracies for grain yield for unrelated test populations have, however, to be improved. Nevertheless, they are already favorable for selecting phenotypic stability of quality traits.
Physiological, metabolic and molecular basis of biennial bearing in apple
(2023) Kofler, Julian; Zörb, Christian
Alternate or biennial bearing in apple (Malus ×domestica Borkh.) is characterized by ‘On’ years with high crop load and inhibited floral bud initiation and ‘Off’ years with little crop load and promoted formation of floral buds, respectively. Apple cultivars differ in their degree of biennial bearing behavior. The cropping irregularity has severe effects on quality and yield of apple harvests in commercial orchards and thereby directly poses an economic risk to apple growers. The aim of this study was to contribute to the understanding of the underlying mechanisms of biennial bearing in apple by analyzing the physiological processes in bud meristems during the time of flower bud induction. A field experiment was conducted during the growing seasons 2015 and 2016 and provided bud meristems of various developmental stages for a variety of analyses. The regular bearing cultivar ‘Royal Gala’ and the biennial bearing cultivar ‘Fuji’ allowed the comparison of two different developmental responses to high and low crop load treatments. Buds from 2-year-old spurs were sampled starting approximately four weeks after full bloom. Histological analysis of bud meristems successfully identified the time point of flower bud initiation in both cultivars at the experimental site. The onset of flower bud initiation was affected by crop load, cultivar and heat accumulation. While heavy cropping delayed the onset in ‘Royal Gala’ trees for 20 days compared to ‘Royal Gala’ trees with no crop load, bud initiation in heavy cropping ‘Fuji’ trees was negligible. ‘Fuji’ trees with no crop load started initiating buds 19 days earlier than ‘Royal Gala’ trees with the same cropping status. Proteomic profiling of the buds sampled during flower bud induction and during flower bud initiation revealed distinct differences in specific protein abundances depending on the cropping status. Buds from trees with a high crop load, where the flower bud initiation was inhibited and the buds primarily remained in a vegetative state, showed a decreased abundance of enzymes belonging to the phenylpropanoid and flavonoid pathways. Specifically, PAL was reduced, which could lead to less active auxin due to the reduced production of chlorogenic acid and thereby inhibiting flower bud formation. Furthermore, increased abundances of histone deacetylase and ferritins were also found in buds from high cropping trees, indicating that histone modification and building up enough iron storage capacities are involved in the vegetative bud development. Buds growing on non-cropping trees with a high rate of flower bud initiation, showed significantly higher concentrations of proteins involved in histone and DNA methylation. Metabolomic profiling and next-generation RNA sequencing showed that thiamine, chlorogenic acid, and an adenine derivative play a role in metabolic pathways promoting early flower bud development in apple, and that tryptophan was more abundant in buds collected from high-cropping trees compared to non-cropping trees. The selection of proteins, metabolites, and genes that the current work produced through its broad, non-targeted approach provides a comprehensive data base for future, more targeted analyses. The results of this study lay a thorough baseline to contribute to the identification of biological markers that are linked to a certain bearing behavior. Such markers can accelerate and facilitate breeding programs aimed at selecting apple cultivars, that are less prone to biennial bearing.
Prediction of hybrid performance in maize using molecular markers
(2008) Schrag, Tobias; Melchinger, Albrecht E.
Maize breeders develop a large number of inbred lines in each breeding cycle, but, owing to resource constraints, evaluate only a small proportion of all possible crosses among these lines in field trials. Therefore, predicting the performance of hybrids by utilising the data available from related crosses to identify untested but promising hybrids is extremely important. The objectives of this thesis research were to develop and evaluate methods for marker-based prediction of hybrid performance (HP) in unbalanced data as typically generated in commercial maize hybrid breeding programs. For HP prediction, a promising approach uses the sum of effects across quantitative trait loci (QTL) as predictor. However, comparison of this approach with established prediction methods based on general combining ability (GCA) was lacking. In addition, prediction of specific combining ability (SCA) is also possible with this approach, but was so far not used for HP prediction. The objectives of the first study in this thesis were to identify QTL for grain yield and grain dry matter content, combine GCA with marker-based SCA estimates for HP prediction, and compare marker-based prediction with established methods. Hybrids from four Dent × Flint factorial mating experiments were evaluated in field trials and their parental inbreds were genotyped with amplified fragment length polymorphism (AFLP) markers. Efficiency for prediction of hybrids, of which both parents were testcross evaluated (Type 2), was assessed by leave-one-out cross-validation. The established GCA-based method predicted HP better than the approach exclusively based on markers. However, with greater relevance of SCA, combining GCA with marker-based SCA estimates was superior compared with HP prediction based on GCA only. Linkage disequilibrium between markers was expected to reduce the prediction efficiency due to inflated QTL effects and reduced power. Thus, in the second study, multiple linear regression (MLR) with forward selection was employed for HP prediction. In addition, adjacent markers in strong linkage disequilibrium were combined into haplotype blocks. An approach based on total effects of associated markers (TEAM) was developed for multi-allelic haplotype blocks. Genome scans to search for significant QTL involve multiple testing of many markers, which increases the rate of false-positive associations. Thus, the TEAM approach was enhanced by controlling the false discovery rate. Considerable loss of marker information can be caused by few missing observations, if the prediction method depends on complete marker data. Therefore, the TEAM approach was improved to cope with missing marker observations. Modification of the cross-validation procedure reflected, that often only a subset of parental lines is crossed with all lines from the opposite heterotic group in a factorial mating design. The prediction approaches were evaluated with the same field data as in the previous study. The results suggested that with haplotype blocks instead of original marker data, similar or higher efficiencies for HP prediction can be achieved. Marker-based HP prediction of inter-group crosses between lines, which were marker genotyped but not testcross evaluated, was not investigated hitherto. Heterosis, which considerably contributes to maize grain yield, was so far not incorporated into marker-based HP prediction. Combined analyses of field trials from multiple experiments of a breeding program provide valuable data for HP prediction. With a mixed linear model analysis of such unbalanced data from nine factorial mating experiments, best linear unbiased prediction (BLUP) values for HP, GCA, SCA, line per se performance, and heterosis of 400 hybrids were obtained in the third study. The prediction efficiency was assessed in cross-validation for prediction of hybrids, of which none (Type 0) or one (Type 1) parental inbred was testcross evaluated. An extension of the established HP prediction method based on BLUP of GCA and SCA, but not using marker data, resulted in prediction efficiency intermediate for Type 1 and very low for Type 0 hybrids. Combining line per se with marker-based heterosis estimates (TEAM-LM) mostly resulted in the highest prediction efficiencies of grain yield and grain dry matter content for both Type 0 and Type 1 hybrids. For the heterotic trait grain yield, the highest prediction efficiencies were generally obtained with marker-based TEAM approaches. In conclusion, this thesis research provided methods for the marker-based prediction of HP. The experimental results suggested that marker-based HP prediction is an efficient tool which supports the selection of superior hybrids and has great potential to accelerate commercial hybrid breeding programs in a very cost-effective manner. The significance of marker-based HP prediction is further enhanced by recent advances in production of doubled haploid lines and high-throughput technologies for rapid and inexpensive marker assays.
Rubber production in Continental Southeast Asia : its potentialities and limitations
(2019) Golbon, Reza; Sauerborn, Joachim
This thesis focuses on three climate-related aspects of Para rubber (Hevea brasiliensis) cultivation in areas where altitudes and latitudes higher than its endemic range create conditions which are labeled nontraditional, suboptimal or marginal for rubber cultivation: 1. rubber yield in relation to the meteorological conditions preceding harvest events, 2. potential geographical shifts in rubber cultivation through climate change and 3. assessment of climate driven susceptibility to South American leaf blight (Pseudocercospora ulei) of rubber.
Spatial combination of sensor data deriving from mobile platforms for precision farming applications
(2019) Zecha, Christoph Walter; Gerhards, Roland
This thesis combines optical sensors on a ground and on an aerial platform for field measurements in wheat, to identify nitrogen (N) levels, estimating biomass (BM) and predicting yield. The Multiplex Research (MP) fluorescence sensor was used for the first time in wheat. The individual objectives were: (i) Evaluation of different available sensors and sensor platforms used in Precision Farming (PF) to quantify the crop nutrition status, (ii) Acquisition of ground and aerial sensor data with two ground spectrometers, an aerial spectrometer and a ground fluorescence sensor, (iii) Development of effective post-processing methods for correction of the sensor data, (iv) Analysis and evaluation of the sensors with regard to the mapping of biomass, yield and nitrogen content in the plant, and (v) Yield simulation as a function of different sensor signals. This thesis contains three papers, published in international peer-reviewed journals. The first publication is a literature review on sensor platforms used in agricultural research. A subdivision of sensors and their applications was done, based on a detailed categorization model. It evaluates strengths and weaknesses, and discusses research results gathered with aerial and ground platforms with different sensors. Also, autonomous robots and swarm technologies suitable for PF tasks were reviewed. The second publication focuses on spectral and fluorescence sensors for BM, yield and N detection. The ground sensors were mounted on the Hohenheim research sensor platform “Sensicle”. A further spectrometer was installed in a fixed-wing Unmanned Aerial Vehicle (UAV). In this study, the sensors of the Sensicle and the UAV were used to determine plant characteristics and yield of three-year field trials at the research station Ihinger Hof, Renningen (Germany), an institution of the University of Hohenheim, Stuttgart (Germany). Winter wheat (Triticum aestivum L.) was sown on three research fields, with different N levels applied to each field. The measurements in the field were geo-referenced and logged with an absolute GPS accuracy of ±2.5 cm. The GPS data of the UAV was corrected based on the pitch and roll position of the UAV at each measurement. In the first step of the data analysis, raw data obtained from the sensors was post-processed and was converted into indices and ratios relating to plant characteristics. The converted ground sensor data were analysed, and the results of the correlations were interpreted related to the dependent variables (DV) BM weight, wheat yield and available N. The results showed significant positive correlations between the DV’s and the Sensicle sensor data. For the third paper, the UAV sensor data was included into the evaluations. The UAV data analysis revealed low significant results for only one field in the year 2011. A multirotor UAV was considered as a more viable aerial platform, that allows for more precision and higher payload. Thereby, the ground sensors showed their strength at a close measuring distance to the plant and a smaller measurement footprint. The results of the two ground spectrometers showed significant positive correlations between yield and the indices from CropSpec, NDVI (Normalised Difference Vegetation Index) and REIP (Red-Edge Inflection Point). Also, FERARI and SFR (Simple Fluorescence Ratio) of the MP fluorescence sensor were chosen for the yield prediction model analysis. With the available N, CropSpec and REIP correlated significantly. The BM weight correlated with REIP even at a very early growing stage (Z 31), and with SAVI (Soil-Adjusted Vegetation Index) at ripening stage (Z 85). REIP, FERARI and SFR showed high correlations to the available N, especially in June and July. The ratios and signals of the MP sensor were highly significant compared to the BM weight above Z 85. Both ground spectrometers are suitable for data comparison and data combination with the active MP fluorescence sensor. Through a combination of fluorescence ratios and spectrometer indices, linear models for the prediction of wheat yield were generated, correlating significantly over the course of the vegetative period for research field Lammwirt (LW) in 2012. The best model for field LW in 2012 was selected for cross-validation with the measurements of the fields Inneres Täle (IT) and Riech (RI) in 2011 and 2012. However, it was not significant. By exchanging only one spectral index with a fluorescence ratio in a similar linear model, it showed significant correlations. This work successfully proves the combination of different sensor ratios and indices for the detection of plant characteristics, offering better and more robust predictions and quantifications of field parameters without employing destructive methods. The MP sensor proved to be universally applicable, showing significant correlations to the investigated characteristics such as BM weight, wheat yield and available N.