Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Genetic diversity of potato for nitrogen use efficiency under low input conditions in Ethiopia
Getahun, Baye Berihun - \ 2017
University. Promotor(en): Richard Visser, co-promotor(en): Gerard van der Linden. - Wageningen : Wageningen University - ISBN 9789463436595 - 219
solanum tuberosum - potatoes - genetic diversity - nitrogen - plant breeding - ethiopia - nutrient use efficiency - aardappelen - genetische diversiteit - stikstof - plantenveredeling - ethiopië - nutriëntengebruiksefficiëntie

Potato is a prime food security crop for smallholder farmers in the highland part of North western Ethiopia. In this region, nutrient availability, especially nitrogen (N) is a major constraint for crop productivity. To obtain insight in the possibility of improving potato for growth under low N input conditions in Ethiopia, we evaluated CxE diploid back cross population, modern European and Ethiopian potato cultivars and local Ethiopian cultivars for their ability to grow and produce tubers under low and high N input conditions. The experiments were conducted under rainfed and irrigation conditions. Eighty-eight Dutch cultivars and 9 Ethiopian cultivars were evaluated in three locations in North-western Ethiopia, in 2013 and in 2015. The two years represent two different growth seasons: rain-fed (June-October 2013) and irrigated cultivation (February-June 2015). Similarly 100 CxE diploid back cross potato genotypes were evaluated in both rainfed and irrigation production seasons in 2014. The Growth of the plants was monitored throughout the growth cycle using canopy cover measurements, with modelled canopy characteristics, and other agronomic traits were measured as per the description. The effect of season and location was further investigated by a GGE Biplot genotype-by-environment interaction analysis, and genetic factors determining phenotypic traits and yield were identified through QTL mapping and association mapping. Ethiopian cultivars showed a remarkable, environment-dependent difference in utilisation of the canopy for tuber production. While total photosynthetic capacity was higher in Ethiopian cultivars than in Dutch cultivars in rainfed production season at Injibara, tuber production was higher in Dutch cultivars. This low radiation use efficiency was not observed in the other rain-fed location (Debre-Tabor). A Genotype by Environment analysis using GGE biplots demonstrates that, Irrespective of the N levels and locations, rainfed production season test environments were grouped as one mega environment and irrigation production season test environments as the other mega environment, indicating most of the variation for yield and nitrogen use efficiency (NUE) in the dataset may be caused by the effect of rain-fed vs irrigation season. Further trials are needed to confirm this result. The QTL mapping with the CxE diploid population and GWAS analysis with the Dutch cultivars discovered both season-environment and N-specific QTL as well as constitutive QTLs. Overall, N availability affects Dutch and Ethiopian cultivars differentially, with strong environmental interaction on canopy and yield traits. Rainfed and irrigated seasons in Ethiopia may require different breeding programs for improved yield under varying fertilizer levels. Both constitutive and environment-specific QTLs were identified that may be targets for breeding prorgams towards improved yield under Ethiopian cultivation conditions.

Greening of Ethiopian Dairy Value Chains: evaluation of environmental impacts and identification of interventions for sustainable intensification of dairy value chains
Vries, Marion de; Yigrem, Sintayehu ; Vellinga, Theun - \ 2016
Wageningen : Wageningen UR Livestock Research (Livestock Research report 948) - 69
dairy herds - dairy performance - improvement - dairy industry - sustainability - nutrient use efficiency - environmental impact - intensification - ethiopia - melkveestapel - melkresultaten - verbetering - zuivelindustrie - duurzaamheid (sustainability) - nutriëntengebruiksefficiëntie - milieueffect - intensivering - ethiopië
Development of a breeding strategy for nitrogen use efficiency in spinach (Spinacia oleracea L.)
Chan Navarrete, J.R. - \ 2016
University. Promotor(en): Edith Lammerts van Bueren, co-promotor(en): Oene Dolstra; Gerard van der Linden. - Wageningen : Wageningen University - ISBN 9789462577961 - 161 p.
spinacia oleracea - spinach - plant breeding - nitrogen - nutrient use efficiency - genetic mapping - nitrogen fertilizers - fertilizer application - genetic diversity - nitrogen response - spinazie - plantenveredeling - stikstof - nutriëntengebruiksefficiëntie - genetische kartering - stikstofmeststoffen - bemesting - genetische diversiteit - stikstofrespons

Spinach (Spinacia oleracea L.) is one of the most consumed leafy vegetables worldwide and it is considered to be highly nutritious. Spinach is a short-cycle leafy crop that has a high demand for nitrogen in order to rapidly come to a harvestable product that has the required dark green colour within a reasonable harvest window. In commercial production of spinach the recovery of N is poor, which may result in environmental pollution. To increase sustainability of both organic and conventional spinach cultivation there is a need to reduce the dependency on high levels of nitrogen. Growers therefore urgently need cultivars with a satisfactory yield under reduced N input conditions. Nitrogen use efficiency (NUE), defined as the ability to produce high biomass per unit N applied, is low in spinach. The present study aims to evaluate spinach genotypes for selectable traits under varying N supply and provide tools and knowledge to facilitate the development of varieties with good yield, quality and stability under low N input. To minimise environmental variation affecting the identification of traits related to NUE a screening method was developed using a hydroponics system. The genetic diversity for NUE related traits was first studied with 24 commercial cultivars under contrasting levels of N supply based on the Ingestad model with a steady-state N application. This demonstrated that the hydroponics screening strategy as a pre-screening tool enabled reliable detection of heritable variation among cultivars for NUE-related traits under optimal as well as suboptimal N input. Shoot dry weight and leaf area were preferred selectable traits for the detection of heritable differences contributing to NUE in spinach. The effect of N application strategy was examined in seven cultivars grown under hydroponics conditions with low and high N levels supplied either as a single bulk N application resembling N fertilization in field cultivation, or a steady-state N application according to Ingestad. The latter application strategy provided more stable and reproducible conditions for determination of genetic differences in NUE under low N conditions for a short-cycle leafy vegetable crop. Several tools for molecular genetic evaluation of NUE in spinach were provided as well, including a SNP marker set for marker-assisted breeding, a genetic mapping population with a corresponding genetic map, and the identification of two major QTL regions contributing to growth under low N conditions. With these tools, an efficient strategy for breeding for NUE efficiency in spinach would include screening under controlled conditions at high and low N using leaf area, biomass and root to shoot ratio as selectable traits, and QTL identification of genetic factors that can be targeted and combined using marker-assisted selection. An in depth genotype by environment interaction analysis using six field trials showed that environmental factors like temperature, soil, and management strongly influence nitrogen availability in the soil in a short cycle crop like spinach. This severely complicates selection and breeding for NUE of spinach under field conditions, and emphasizes the importance of performing trials under better controllable conditions for genetic dissection of NUE and discovery of genetic factors contributing to NUE. It also underscores the importance of validating these findings in various field trials. Multi-environment field trials with different levels of N fertilization will then allow selection of cultivars that combine stable performance under various low input growing conditions with high yields under more favorable conditions.

Variation in phosphorus acquisition efficiency among maize varieties as related to mycorrhizal functioning
Wang, X.X. - \ 2016
University. Promotor(en): Thomas Kuijper; Ellis Hoffland, co-promotor(en): G. Feng. - Wageningen : Wageningen University - ISBN 9789462577985 - 168 p.
zea mays - mycorrhizas - maize - phosphorus - nutrient use efficiency - vesicular arbuscular mycorrhizas - nutrient uptake - varieties - mycorrhizae - maïs - fosfor - nutriëntengebruiksefficiëntie - vesiculair-arbusculaire mycorrhizae - voedingsstoffenopname (planten) - rassen (planten)

Phosphorus (P) is a main limiting factor for agricultural production, but overusing P fertilizer has brought serious environmental damages in China. Improving P acquisition efficiency of agricultural crops is an urgent topic. It has been proven repeatedly that arbuscular mycorrhizal fungi (AMF) and genetic diversity within one crop plant can play important roles in P uptake by crops. The main objective of this thesis was to understand the role of the arbuscular mycorrhizal symbiosis in P acquisition efficiency of different maize varieties. The specific objectives were to test: 1) how P uptake by maize varieties responds to colonization by the native AMF community in the field; and 2) whether AMF hyphae take up P for plants from phytate which is the most abundant organic P form in soil; 3) whether mixing maize cultivars can improve maize productivity and whether AMF can play a role in this system; and 4) how AMF species (or community) legacy affects successional maize growth. In this thesis, I combined field experiments and greenhouse experiments and made use of maize genetic diversity and (native) AMF to improve P (including inorganic and organic P) acquisition.

The effects of one single AMF species on maize growth and nutrient uptake have been well studied, but how maize varieties respond to the native AMF community has been insufficiently studied. In Chapter 2, I focused on how maize varieties responded to the native AMF community by using rotated cores in the field, to compare mycorrhizal responsiveness among 20 maize varieties and the difference of the AMF native community of four maize varieties (two old landraces and two modern hybrids). The results indicated that, 1) increased P fertilizer significantly reduced mycorrhizal responsiveness in the field; 2) a complicated relationship exists between mycorrhizal responsiveness in the field and pot experiment; 3) there was no significant difference between old and modern maize varieties in terms of mycorrhizal responsiveness and colonization; 4) there were only small differences in AMF community composition among the four maize varieties. By comparing mycorrhizal responsiveness of maize varieties between in the pot experiment and in the field experiment (with in-growth cores), I found mycorrhizal responsiveness of maize varieties in the pot experiment was significantly larger than that in the field experiment. Thus, mycorrhizal responsiveness of varieties within one cereal plant species tested classically in pots may not present their realistically mycorrhizal responsiveness in field.

Phytate is the most abundant form of organic P in soil. To explore the potential of phytate utilization by plants is agriculturally and environmentally essential. Increased P nutrition of mycorrhizal plants derived from phytate has been reported, indicating that phytate can be a potential P source. However, earlier studies assessed phytate use by using acid phosphatase rather than phytase, and did not consider that phytate adsorption could lead to phosphate release. Thus, I investigated the effect of mycorrhizal hyphae-mediated phytase activity on P uptake by maize in Chapter 3. I conducted a rhizobox experiment to explore phytate use by mycorrhizal hyphae for two maize varieties. The results showed that: 1) phytate addition increased phytase and acid phosphatase activity, and resulted in increased P uptake and plant biomass; 2) the increase in P uptake and biomass were correlated with the increase of phytase activity but not with the increase of acid phosphatase activity; 3) lower phytate addition rate increased, but higher addition rates decreased hyphal length density. I conclude that P from phytate can be used by mycorrhizal plants, but that the phytate contribution to plant nutrition is likely limited. Phytase activity is a more relevant indicator to assess phytate use. In addition, there was a significant interaction between maize varieties and AMF species in taking up P from phytate, which implies there is a possibility to combine different maize varieties to increase total yield using phytate. Besides, I used an empirical relationship to assess phosphate release due to phytate addition. My calculation implies that phosphate desorption cannot be ignored when assessing phytate use, particularly when a large amount of phytate is applied as a P source.

In multispecies natural ecosystems, AMF can play a key role in enhancing plant productivity. However, their role in enhancing crop productivity in mixed cropping systems is still poorly understood. In Chapter 4, I conducted both greenhouse and field experiments to investigate whether mixing maize varieties with different P acquisition strategies could lead to overyielding, and what roles AMF play in this system with two maize varieties. The results showed that mixing maize varieties resulted in overyielding, both in P uptake and shoot biomass, but only when plants were mycorrhizal. At the same time, I found higher hyphal length density and higher AMF diversity in mixtures compared to the monocultures in the field experiment, and higher colonization rate and higher hyphal length density in mixtures in the pot experiment. Thus, I propose that overyielding by mixing maize varieties might be due to increased mycorrhizal performance leading to more P uptake. I also used the partitioning formula to calculate the contribution through the selection effect and complementarity effect to overyielding. I found that the increase of the total yield and P uptake in mixtures was largely due to complementarity effect, implying that relative overyielding and enhanced P uptake were not due to enhanced competitive ability by the larger variety. The results of Chapter 4 suggest that mixing mycorrhizal maize varieties might be beneficial for enhancing productivity and P uptake efficiency.

Plant - soil feedback experiments have shown that AMF can play a crucial role in determining the direction and magnitude of that feedback. Most studies investigated plant - soil feedback dynamics between different plant species. However, it is unknown to what extent one variety of an agricultural crop can affect the performance of another variety of that same crop through plant - soil feedback. In Chapter 5, I carried out a two-phase experiment in a greenhouse, including conditioning phase and test phase to determine plant - soil feedbacks in the absence and presence of AMF species or community, to test the effects of AMF on feedback dynamics. The results in Chapter 5 showed that: 1) in the conditioning phase, both maize varieties were differentially influenced by different AMF species compared to non-mycorrhizal control; 2) in the feedback phase, non-mycorrhizal maize exhibited negative feedback dynamics for biomass and P-uptake; 3) on the feedback phase, mycorrhizal maize generally exhibited positive feedback dynamics for biomass and P-uptake. The interaction coefficient was largest with the mixture of three different AMF species. The interaction coefficient for shoot and P uptake were significantly correlated with the coefficient for mycorrhizal colonization. These results imply that different maize varieties are affected differently by different AMF species, thereby influencing the productivity of the subsequent maize variety. The results also raise questions how AMF influence rhizosphere biota and how maize varieties may select more beneficial AMF.

In Chapter 6, I integrate the results from previous chapters. I discuss possible relationships between (negative) plant - soil feedback effect (due to pathogen) and the mycorrhizal effect on overyielding and improved P uptake due to mixing maize varieties (compared to the monoculture). I also discuss the linkage between phosphorus acquisition efficiency and mycorrhizal responsiveness within one crop species, and the relationship between plant genetic diversity and plant - soil feedback effects, and try to come up with a conceptual model how mixing maize varieties in the presence of AMF could be beneficial.

Nitrogen use efficiency in potato : an integrated agronomic, physiological and genetic approach
Ospina Nieto, C.A. - \ 2016
University. Promotor(en): Paul Struik; Edith Lammerts van Bueren, co-promotor(en): Gerard van der Linden. - Wageningen : Wageningen University - ISBN 9789462576469 - 177 p.
solanum tuberosum - potatoes - nitrogen - nutrient use efficiency - plant breeding - crop physiology - plant physiology - quantitative trait loci - cultivars - aardappelen - stikstof - nutriëntengebruiksefficiëntie - plantenveredeling - gewasfysiologie - plantenfysiologie - loci voor kwantitatief kenmerk

Nitrogen (N) fertilizers increased food production over the last 60 years, but also contributed significantly to the use of fossil energy and the total amount of reactive N in the environment. Agriculture needs to reduce N input and increase nitrogen use efficiency (NUE). Legislation like the Nitrate Directive (91/767/EEC) and the Water Framework Directive (2000/60/EC) forces a reduction in N supply in crop production. The effects of this constraint on yield and quality of potato are expected to be significant since N plays an important role in the vegetative development and production of potato. Considerable amounts of N are needed as N recovery is notoriously low due to the small and shallow roots. The overall aim of this thesis is to improve the nitrogen use efficiency of potato under low nitrogen supply. Specific aims are i) to understand the N effects on potato performance, especially under low N input, ii) to quantify the genotypic variation under contrasting N inputs, iii) to identify quantitative trait loci associated with the crop’s response to nitrogen. We used ecophysiological models to dissect the canopy development into biological meaningful parameters as phenotyping tools. Two potato populations (a set of tetraploid cultivars and a biparental diploid population) were phenotyped in the field under two contrasting N levels. Additionally, a set of 6 cultivars from three maturity groups (early, middle and late) were phenotyped in more detail under 5 nitrogen conditions combining two input levels and two fertilizers types plus a control without nitrogen fertilisation. The curve-fit parameters were, together with other agronomical traits, used in the agronomic and genetic analysis. Our approach using the ecophysiological models captured the phenotypic response to N, enhancing the interpretation of the nitrogen effects and of the differences among maturity types. The nitrogen effects on canopy development resulted in large differences in light interception, tuber yield, tuber size distribution and nitrogen uptake. There were differences in the response to nitrogen between the diploid biparental population and the set of tetraploid cultivars. In general, in the diploid population, having less vigour and therefore less potential to respond to the extra nitrogen, the time required to complete each phase of the canopy development was longer than in the set of tetraploids. In the set of cultivars the rate of early vegetative growth was higher, the onset of the phase with maximum canopy cover was earlier, and the duration of maximum canopy was longer than for the diploid population. However, in both the diploid and the tetraploid population maturity was the major factor accounting for genetic variation in canopy development and tuber development traits. The genotypic differences were reflected in quantitative trait loci that were either N dependent or N independent, with pleiotropic regions affecting most of the maturity-related traits. Few traits showed quantitative trait loci on common regions that were not maturity related like those on chromosomes 2 and 6 (association mapping) or linkage groups ma_VI, pa_VIII pa_XI. Maturity obscures other genotype-dependent physiological traits; therefore it is imperative to find traits that are responsible for genotypic variation, but not related to maturity type. Moreover the results showed that nitrogen use efficiency under low nitrogen input is higher than under high nitrogen input, and higher for late cultivars than for early cultivars. Therefore, breeding for nitrogen use efficiency under low input requires direct selection combined with good response to extra nitrogen and should be done within each maturity group. Finally in a broader context we discussed the need of high-throughput phenotyping in breeding for complex traits, like those involving efficiency, to make the most of the large amount of genetic data, all possible based on advances in technology in remote sensing and images analysis.

Keywords: Association mapping, Breeding for low input, Canopy development, Maturity type, Nitrogen use efficiency, Potato, Solanum tuberosum, Quantitative trait loci.

Evaluation of king oyster mushroom strains (Pleurotus eryngii) on selective lignin degradation in wheat straw: An update
Sonnenberg, A.S.M. ; Visser, M.H.M. ; Lavrijssen, B. ; Cone, J.W. ; Hendrickx, P.M. - \ 2016
Wageningen : Wageningen UR (PPO/PRI report 2016-4) - 21 p.
mushrooms - edible fungi - lignin - postharvest quality - agaricus bisporus - composts - nutrient use efficiency - pleurotus eryngii - lentinula edodes - wheat straw - miscanthus - straw - paddestoelen - eetbare paddestoelen - lignine - kwaliteit na de oogst - compost - nutriëntengebruiksefficiëntie - tarwestro - stro
The collection of Plant Breeding contains a large number of strains of Pleurotus eryngii and Lentinula edodes, two fungi producing edible mushrooms and also known by their selective degradation of lignin in lignocellulosic materials.
Rekenregels van de KringloopWijzer : achtergronden van BEX, BEA, BEN, BEP en BEC: actualisatie van de 4 maart 2014 versie
Schroder, J.J. ; Šebek, L.B. ; Reijs, J.W. ; Oenema, J. ; Goselink, R.M.A. ; Conijn, J.G. ; Boer, J. - \ 2016
Wageningen UR (PRI-rapport 640) - 103 p.
dierhouderij - duurzame veehouderij - melkproducerende dieren - melkveehouderij - landbouw - mestbeleid - modules - berekening - dierlijke meststoffen - excretie - emissiereductie - nutriëntengebruiksefficiëntie - kringlopen - animal husbandry - sustainable animal husbandry - milk yielding animals - dairy farming - agriculture - manure policy - calculation - animal manures - excretion - emission reduction - nutrient use efficiency - cycling
Bijgaand rapport beschrijft de rekenregels van de KringloopWijzer. De KringloopWijzer is een model waarmee agrarische ondernemers op basis van hun eigen bedrijfsgegevens een schatting kunnen maken van de benutting van aangevoerde nutriënten, met name stikstof (N) en fosfor (P), en van de omvang en aard van verliezen aan N, P en koolstof (C). Die schatters kunnen gebruikt worden voor het benoemen van verbeterpunten binnen het bedrijf en als verantwoording naar overheden en verwerkers. Voor de overheid biedt de KringloopWijzer mogelijkheden om generieke wetgeving te vervangen door maatwerk. Voor de verwerkende industrie is het bovendien mogelijk om het streven naar duurzaamheid meetbaar te maken ten behoeve van consumenten. De hier beschreven rapportversie bevat een aantal verbeteringen en aanvullingen ten opzichte van de versie uit 2014. Ze heeft bovendien niet langer betrekking op alleen melkvee en ruwvoergewassen, maar is ook geschikt voor bedrijven met een neventak akkerbouw en/of een neventak hokdieren. De rekenregels zijn waar mogelijk voorzien van onderbouwende referenties. Aan een verdere toetsing van deze rekenregels wordt nog voortdurend onderzoek verricht.
De P-benutting door het vee van melkveebedrijven, de impact van minimumwaarden en een tool voor verbetering
Oenema, J. ; Aarts, H.F.M. - \ 2015
Plant Research International (PRI) (PRI Rapport ) - 25 p.
cattle - dairy cattle - cattle feeding - phosphate - excretion - use efficiency - nutrient use efficiency - efficiency - feed conversion efficiency - rundvee - melkvee - rundveevoeding - fosfaat - excretie - gebruiksefficiëntie - nutriëntengebruiksefficiëntie - efficiëntie - voederconversievermogen
In 2013 was de P(benutting van de Nederlandse melkveestapel gemiddeld 30%. De benutting neemt de laatste twee decennia toe met ongeveer 0.25 procentpunt per jaar, met name door het beter presteren van melkkoeien en de afname van het aandeel jongvee. Om onder het plafond van 84.9 miljoen kg fosfaat(excretie te blijven zal een uitbreiding van de melkproductie met 10% gepaard moeten gaan met een verbetering van de benutting van de veestapel met 0.8 procentpunt; een uitbreiding met 20% of 30% verlangt een verbetering van respectievelijk 2.7 procentpunt en 4.5 procentpunt. Bij indeling van bedrijven in klassen, naar grondsoort en intensiteit (melk/ha), blijkt dat de 10% best scorende bedrijven een benutting realiseren die 5.4 tot 7.6 procentpunt hoger is dan die van de 10% slechts scorende. Als de 10%, 20% of 30% slechts scorende bedrijven gedwongen worden de minimum prestatie te realiseren van de resterende 90%, 80% of 70% leidt dit per stap tot een verbetering van 0.2 procentpunt; bij 30% dus tot 0.6 procentpunt. Besproken wordt de opzet van een tool waarmee de veehouder wordt geholpen de P(benutting te verbeteren.
Exploring options for improving water and nitrogen use efficiency in crop production systems
Qin, W. - \ 2015
University. Promotor(en): Oene Oenema, co-promotor(en): C. Hu; Marius Heinen. - Wageningen : Wageningen University - ISBN 9789462575035 - 188
gewasproductie - agrarische productiesystemen - watergebruiksrendement - stikstof - nutriëntengebruiksefficiëntie - mulchen - fertigatie - crop production - agricultural production systems - water use efficiency - nitrogen - nutrient use efficiency - mulching - fertigation

Water and nitrogen (N) are two key limiting factors in global crop production. However, the optimization of water and N use is often studied separately, and the interactions between water and N use in crop production are often neglected. Lack of systematic and quantitative understanding of the interactions between water and N use may lead to misleading and/or biased recommendations. The main objective of this thesis research was ‘to increase the understanding of interactions between water and N use in crop production’. The specific objectives were (i) to analyse water and N use and their interactions in crop yields and in water and N use efficiencies (WUE and NUE), and (ii) to explore options for increasing crop yields and water and N use efficiencies simultaneously.

In this thesis, I combined the use of literature review and meta-analysis, long-term field experiments and soil-crop modelling to quantify relationships between water and N use and their interactions in crop yields, WUE and NUE, and to explore options for improving the productivity and sustainability of two important and contrasting crop systems (i.e., annual cereal and perennial orange systems).

In arid and semi-arid regions, such as the Loess Plateau, I found that the water loss via soil evaporation was large as much as 60 to 70% of total rainfall and thereby significantly limited wheat yields. Soil mulching can effectively reduce soil evaporation thereby increasing crop yields by up to 60%. In sub-humid regions, the productivity and sustainability of rainfed wheat-soybean rotation systems can be constrained by soil fertility and other factors besides water and nutrient management. Fertilization and soil organic amendments greatly increased wheat yield and WUE, but decreased NUE.

In advanced fertigated orange production systems, a main challenge is to optimize water and N use for optimal yield while minimizing environmental pollution. Fertigation provides opportunities to simultaneously optimize water and N use in orange production systems. Optimization of water and N supply is, however, complicated in practice due to erratic and uncontrollable rainfall, which may lead to large incidental losses. Improving water and N input can significantly and simultaneously increase orange yield, WUE and NUE (by 20, 30 and 40% respectively). Importantly, even with optimal water and N input levels, fractionation (split) strategies can significantly increase orange yield and reduce N losses.

In conclusion, rainfed cereal crop yields, WUE and NUE in dryland agriculture can be increased by up to 60%, with currently available knowledge and soil mulching techniques. In many regions in the world, there is still a large gap between observed farm yield and attainable yield by best management. Given large potentials in low-performing agricultural systems, investments in knowledge and education, infrastructures and subsidies should also be prioritized for these regions. Potentially, this will significantly contribute to local and global food security at large.

Snelle meettechnieken voor nutriëntenbenutting bij landbouwhuisdieren
Vrolijk, M. ; Goselink, R.M.A. ; Veldkamp, T. - \ 2015
Wageningen : Wageningen UR Livestock Research (Livestock Research rapport 902) - 43
vee - veevoeding - nutriëntengebruiksefficiëntie - voedingsstoffenopname (mens en dier) - meettechnieken - voedingsfysiologie - livestock - livestock feeding - nutrient use efficiency - nutrient intake - measurement techniques - nutrition physiology
Efficient feeding of animals in livestock production deserves constant attention. Feed is input for milk, meat and egg production. It is a challenge to use nutrients as efficiently as possible, and produce ‘more with less’. Feeding the animals at their requirements can be improved if the effects of nutrient intake can be measured within a short time. This project made an overview of possible ‘rapid measuring techniques’ to be used in the near future. Each technique was scored for relevance, technical feasibility, practical application and the investment needed for development (time and money). From an expert workshop, measuring by means of sensor boluses or fluorescent markers as well as manure analysis, were defined as most promising for future research and practice.
Physiology and genetics of root growth, resource capture and resource use efficiency in lettuce (Lactuca sativa L.)
Kerbiriou, P.J. - \ 2014
University. Promotor(en): Edith Lammerts van Bueren; Paul Struik, co-promotor(en): Tjeerd-Jan Stomph. - Wageningen : Wageningen University - ISBN 9789462570863 - 179
lactuca sativa - slasoorten - cultivars - groei - wortels - scheuten - plantenontwikkeling - nutriëntengebruiksefficiëntie - voedingsfysiologie - watergebruiksrendement - genetische variatie - droogteresistentie - tolerantie van variëteiten - genotype-milieu interactie - biologische plantenveredeling - lettuces - growth - roots - shoots - plant development - nutrient use efficiency - nutrition physiology - water use efficiency - genetic variation - drought resistance - varietal tolerance - genotype environment interaction - organic plant breeding
Sturen op bodemvruchtbaarheid
Oenema, J. ; Verloop, J. - \ 2014
Nieuwsbrief Koeien & Kansen (2014)40. - p. 3 - 3.
bodemvruchtbaarheid - nutriëntengebruiksefficiëntie - bodembeheer - veehouderij - melkveehouderij - soil fertility - nutrient use efficiency - soil management - livestock farming - dairy farming
Een goede bodemvruchtbaarheid is de basis voor efficiënt nutriëntengebruik. De afgelopen 14 jaar hebben Koeien & Kansen-bedrijven de nutriënten N en P op efficiënte wijze benut zonder de (gemiddelde) bodemvruchtbaarheid aan te tasten.
Perspectieven voor veredeling op stikstofefficiëntie bij sluitkool (Literatuuroverzicht)
Hospers-Brands, M. ; Ji, Y. ; Struik, P.C. ; Lammerts Van Bueren, E. - \ 2014
Driebergen : Louis Bolk Instituut - 36
brassica oleracea var. capitata - plantenveredeling - stikstof - nutriëntengebruiksefficiëntie - literatuuroverzichten - biologische landbouw - plant breeding - nitrogen - nutrient use efficiency - literature reviews - organic farming
Kool is een belangrijk gewas in Nederland. Koolsoorten vragen veel stikstof (ca. 300 kg N/ha)voor een goede groei, dikwijls meer dan binnen de huidige regelgeving in een biologische vruchtwisseling kan worden geleverd. Stikstof verhoogt de opbrengst, maar bij een hoog stikstofaanbod bereikt de opbrengst een plafond. Er is in het verleden veel onderzoek gedaan om de bemesting te optimaliseren. Voor een verdere verduurzaming van de teelt is het de vraag welke rassen robuust genoeg zijn om bij een beperkte hoeveelheid stikstof en wisselende weers- en groeiomstandigheden toch een economisch acceptabele en stabiele opbrengst te geven. En welke planteigenschappen spelen daarbij een cruciale rol? Door middel van literatuuronderzoek, gesprekken met deskundigen en veldbezoeken is nagegaan wat de perspectieven zijn om te veredelen op stikstofefficiëntie bij koolsoorten, met name bij sluitkool. Stikstofefficiëntie is de resultante van twee componenten: stikstofopname-efficiëntie en stikstofgebruiksefficiëntie. Deze aspecten moeten steeds in onderlinge relatie onderzocht worden, omdat rassen diverse combinaties van strategieën kunnen ontwikkelen om efficiënt met een laag stikstofaanbod om te kunnen gaan. Weliswaar is het meeste onderzoek naar stikstofefficiëntie bij Brassica gewassen gedaan aan koolzaad, Chinese kool en bloemkool, maar uit dit voorliggende onderzoek zijn goede aanknopingspunten gevonden voor verbetering van stikstofefficiëntie bij sluitkool. Voor de opname van stikstof is goede beworteling een voorwaarde. Kool blijkt diep te kunnen wortelen en efficiënt stikstof uit de bodem te kunnen opnemen. Er is echter nog geen onderzoek gedaan naar mogelijke rasverschillen in beworteling (diepte, intensiteit, en plasticiteit) bij sluitkool onder een laag stikstofaanbod. Omdat in de biologische teelt stikstof bij koude minder makkelijk beschikbaar komt, is het belangrijk om in bewortelingsonderzoek vooral ook vroege rassen te betrekken. Daarbij is het tevens van belang diverse locaties in het onderzoek te betrekken omdat verschillen in beworteling niet onder alle omstandigheden tot expressie komen. Uit de literatuur valt af te leiden dat voor kool vooral winst te behalen is bij het verbeteren van de gebruiksefficiëntie. Daarbij lijkt het van belang dat het omblad zo lang mogelijk, tot aan de oogst, actief blijft teneinde de stikstofopname te stimuleren. Ook de herverdeling van stikstof van het oude blad naar het jonge (binnen)blad dat de kool vormt en dat niet fotosynthetisch actief kan zijn, is belangrijk. Deze gebruiksprocessen en de verhouding tussen omblad en jong blad en daarmee samenhangende gebruiksprocessen kunnen verschillen voor vroege, middelvroege en late rassen. Nader onderzoek moet uitwijzen wat de ideale verhouding van omblad en kool (harvest index) is in relatie tot stikstofefficiëntie, en of bladstand en bladopbouw daarbij een rol spelen. Daarbij zou het interessant kunnen zijn te onderzoeken of ook andere selectiecriteria van belang kunnen zijn, zoals de bebladeringsindex (bladoppervlak/grondoppervlak, m2/m2), specifiek bladoppervlak (bladoppervlak/bladgewicht, cm2/g), nitraatreductase en / of chlorofylgehalte of -fluorescentie.
Nutrient use efficiency in the food chain of China
Ma, L. - \ 2014
University. Promotor(en): Oene Oenema, co-promotor(en): Gerard Velthof; F. Zhang. - Wageningen : Wageningen University - ISBN 9789461738448 - 193
stikstofmeststoffen - fosformeststoffen - voedselketens - voedselzekerheid - kosten voor voedsel - milieueffect - nutrientenbeheer - kringlopen - nutriëntengebruiksefficiëntie - china - nitrogen fertilizers - phosphorus fertilizers - food chains - food security - food costs - environmental impact - nutrient management - cycling - nutrient use efficiency

Key words: Nitrogen, phosphorus, food chain, food pyramid, food system, food security, food cost, environmental impacts, nutrient cycling, nutrient management

Nitrogen (N) and phosphorus (P) fertilizer applications have greatly contributed to the increased global food production during the last decades, but have also contributed to decreasing N and P use efficiencies (NUE and PUE) in the food production - consumption chain, and to increased N and P losses to air and water, with major ecological implications.

The aim of this thesis is to increase the quantitative understanding of N and P flows and losses in the food production - consumption chain in China at regional level in the past 30 years and to develop strategies to increase NUE and PUE in the food chain. A novel ‘food chain’ approach and the NUFER model were developed to analyse N and P flows in crop production, animal production, food processing and retail, and households. Data were derived from statistical sources, literature and field surveys.

Between 1980 and 2005, NUE and PUE decreased in crop production, increased in the animal production and decreased in the whole food chain. Total N losses to water and atmosphere almost tripled between 1980 (14.3 Tg) and 2005 (42.8 Tg), and P losses to water systems increased from 0.5 to 3.0 Tg. There were significant regional differences in NUE, PUE, and N and P losses; regions with high N and P losses were in Beijing and Tianjin metropolitans, Pearl River Delta, and Yangzi River Delta. Urban expansion is a major driving force for change; total N losses increased 2.9 folds, and P losses increased even 37 folds during the development of Beijing metropolitan, between 1978 and 2008. Scenario analyses indicated that implementation of a package of integrated nutrient management measures, combined with diet changes and increased imports of animal food and feed, are the most effective management options for increasing NUE and PUE, and for decreasing N and P losses.

Application of the food chain approach and the NUFER model can help policy makers in China to plan food production - consumption chains, and thereby manage N and P flows in this chain at regional level.

Cattle slurry on grassland - application methods and nitrogen use efficiency
Lalor, S.T.J. - \ 2014
University. Promotor(en): Oene Oenema, co-promotor(en): Jaap Schroder; Egbert Lantinga. - Wageningen : Wageningen University - ISBN 9789461738264 - 184
graslanden - rundveedrijfmest - bemesting - nutriëntengebruiksefficiëntie - stikstof - melkveehouderij - emissiereductie - grasslands - cattle slurry - fertilizer application - nutrient use efficiency - nitrogen - dairy farming - emission reduction

Cattle slurry represents a significant resource on grassland-based farming systems. The objective of this thesis was to investigate and devise cattle slurry application methods and strategies that can be implemented on grassland farms to improve the efficiency with which nitrogen (N) in cattle slurry is recycled. The research focused on slurry application method and timing techniques that have been shown to reduce ammonia emissions following slurry application. Further, it was investigated whether the reduction in ammonia emissions translates into an increase in the N fertiliser replacement value (NFRV) of applied slurry. The study also included an economic analysis of the costs and benefits of low-emission slurry application methods, including a sensitivity analysis of the impact of costs that are likely to vary between farms.

A modelling study showed that low-emission application methods, which reduce herbage contamination and therefore permit slurry application into taller grass swards, increase the opportunity for application in spring when the slurry NFRV is relatively high due to the prevailing weather conditions that reduce ammonia volatilisation. The extent to which the opportunity for application in spring can be extended is affected by soil type, with more opportunity being afforded on more freely drained soil types. The extent to which herbage contamination is reduced by the low-emission application method was also affected by the grass height at application. Application methods that permit damage free traffic into taller swards permit greater potential to extend the opportunity for spring application.

In multi-year and multi-site field experiments, the NFRV of cattle slurry applied to grassland was increased by application using trailing shoe in short grass swards compared with conventional broadcast application using splash-plate. The NFRV was also higher when slurry was applied in April compared with June. However, there was no advantage over splash-plate in using the trailing shoe application method in taller grass swards, as the damage to the sward by the machinery traffic negated the benefits of reduced ammonia volatilisation.

An economic assessment showed that there was a net cost associated with adopting low-emission application methods on farms. The benefit of mineral N fertiliser savings due to ammonia emission abatement was not sufficient to offset the additional costs of adoption. The sensitivity analysis showed that the factors that had greatest impact on the costs were the assumed ammonia emission abatement potentials, the volume of slurry being applied annually with each machine, and the hourly work rate of the equipment. The capital costs of increased tractor power contributed significantly to the total capital costs of adoption of low-emission equipment.

The results of this work were combined with literature data to devise updated NFRVs for slurry application to grassland in Ireland. The new advice includes differentiation of NFRVs based on application method, timing and residual N release. This represents a major step forward in advice to farmers for slurry application, and farmers have responded through improved management of application timing. The study shows that the combination of more application in spring and adopting low-emission application methods have a role to play in improving N efficiency from slurry in the future.

Popeye gaat duurzaam! Groene Veredeling 12 juni 2013
Linden, Gerard van der - \ 2013
plant breeding - spinach - leafy vegetables - field vegetables - nutrient use efficiency - molecular breeding - sustainable agriculture - organic farming
Lucerne (Medicago sativa) or grass-clover as cut-and-carry fertilizers in organic agriculture
Burgt, G.J.H.M. van der; Eekeren, N.J.M. van; Scholberg, J.M.S. ; Koopmans, C.J. - \ 2013
In: The role of grasslands in a green future : threats and perspectives in less favoured areas / Helgadóttir, A., Hopkins, A., EGF (Grassland science in Europe 18) - p. 123 - 125.
bemesting - groenbemesters - organische meststoffen - veldproeven - vollegrondsteelt - medicago sativa - luzerne - grasklaver - biologische landbouw - nutriëntengebruiksefficiëntie - fertilizer application - green manures - organic fertilizers - field tests - outdoor cropping - lucerne - grass-clover swards - organic farming - nutrient use efficiency
Onfarm nitrogen fixation is a driving force in organic agriculture. The efficiency with which this nitrogen is used can be increased by using lucerne (Medicago sativa) or grassclover directly as sources of fertilizer on arable land: cutandcarry fertilizers. In two arable crops, the use of lucerne and grassclover as fertilizers was compared with the use of poultry manure and slurry. The nitrogenuse efficiency at crop level was comparable or better for the cutandcarry fertilizers as compared to the animal manures. The relative P and K content of these fertilizers came closer to the crop demand than that of the poultry manure. Crop yields were comparable or better when using lucerne or grassclover as fertilizer. It is concluded that cutandcarry fertilizers are a serious alternative for manure as part of an overall farm soil fertility strategy.
Kleinschalige bioraffinage in de Achterhoek; een duurzame oplossing voor het mestprobleem
Sanders, J.P.M. ; Doorn, W.J. van; Krimpen, M.M. van; Cremers, H. - \ 2013
Wageningen : Wageningen Universiteit, Livestock Research - 34
voedermiddelbewerking - grasmaaisel - maïs - bioraffinage - nutriëntengebruiksefficiëntie - mestoverschotten - regionale ontwikkeling - rundveevoeding - varkensvoeding - melkveehouderij - achterhoek - nederland - biobased economy - feed processing - grass clippings - maize - biorefinery - nutrient use efficiency - manure surpluses - regional development - cattle feeding - pig feeding - dairy farming - netherlands
We kampen in Nederland al decennia met een mestprobleem, in feite een mest overschot. In dit rapport worden nieuwe aanpakken van dit probleem voorgesteld, gedeeltelijk gecombineerd met verlaging van mineralen in het voer. De nieuwe aanpak wordt mogelijk indien we er in slagen de efficiëntie van de diervoeders te verbeteren en indien we de belangrijkste componenten van het diervoeder, eiwit en de energie behoefte van de dieren, in Nederland zelf te produceren. Bioraffinage van met name gras en in op termijn ook van mais, is doorslaggevend omdat we daarmee de componenten voor de rundveevoeders kunnen ontsluiten waardoor een hoger rendement wordt bereikt. Door graseiwit in te zetten als varkensvoeder zijn we niet langer afhankelijk van de import van sojaschroot en andere restproducten uit de plantaardige olie verwerkende industrie. Wanneer we deze bioraffinage uitvoeren in kleinschalige fabriekjes, voor de maisraffinage het liefst gekoppeld aan een biogas vergistingsinstallatie, dan kunnen de mineralen die niet voor het dier nodig zijn, direct zonder dure concentreringsbehandelingen naar het agrarische veld terug gebracht worden als bemesting.
Verhoging benutting stikstof en fosfaat door rijenbemesting
Geel, W.C.A. van - \ 2013
bemesting - rijenbemesting - nutriëntengebruiksefficiëntie - stikstof - fosfaat - veldproeven - consumptieaardappelen - aardappelen - zaai-uien - uien - akkerbouw - fertilizer application - band placement - nutrient use efficiency - nitrogen - phosphate - field tests - table potatoes - potatoes - spring-sown onions - onions - arable farming
Poster met onderzoeksinformatie.
Nieuwe bijmestsystemen en -strategieën voor aardappel op zand- en lössgrond : resultaten veldonderzoek
Schans, D.A. van der; Kroonen-Backbier, B.M.A. ; Geel, W.C.A. van; Malda, J.T. - \ 2013 2013 (2013)6 mei.
bemesting - aardappelen - stikstof - monitoring - beslissingsondersteunende systemen - veldproeven - nutriëntengebruiksefficiëntie - zandgronden - lössgronden - akkerbouw - landbouwkundig onderzoek - fertilizer application - potatoes - nitrogen - decision support systems - field tests - nutrient use efficiency - sandy soils - loess soils - arable farming - agricultural research
PPO en Altic voeren voor het Masterplan MineralenManagement (MMM) onderzoek uit naar mogelijkheden om de stikstofbenutting van aardappel te verbeteren door de ontwikkeling van nieuwe of verbeterde stikstofbijmestsystemen. Die systemen zijn in 2011/2012 ontworpen en er is een plan van aanpak opgesteld om ze gedurende twee jaar te toetsen in veldproeven. Dit (tussen)rapport gaat in op de veldproeven van 2012 die zijn uitgevoerd op een zuidoostelijke zandgrond (Vredepeel) en op löss (Hulsberg).
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