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CHALLENGES FOR PLANT NUTRITION IN CHANGING ENVIRONMENTS International Workshop and Meeting of the German Society of Plant Nutrition 2012 University of Bonn September 5 – 8, 2012 Book of Abstracts Table of Contents Plenary Session: Introductory talks ................................................. 2 Plenary Session S1: Processes on leaf surfaces ................................. 5 Plenary Session S2: Plant water relations .......................................... 14 Plenary Session S3: Nutrient dynamics in changing environments .... 26 Plenary Session S4: Crop responses to nutrient imbalances ............. 38 Plenary Session S5: Phenotyping and early stress responses ........... 80 Poster Session P1: Fertilization (inorganic) ...................................... 92 Poster Session P2: Fertilization (organic) / Soil amendments ........ 110 Poster Session P3: Nutrient efficiency / Genomics ......................... 131 Poster Session P4: Root physiology / Root-soil interactions........... 148 Poster Session P5: Physiological response to abiotic stress .......... 169 Poster Session P6: Physiological response to nutrient imbalances 182 Poster Session P7: Nutrients and ecosystems / Climate change ... 200 Poster Session P8: Signalling / Quality / Phenotyping .................... 215 1 DGP Meeting September 5-9, 2012 Plenary Session: Introductory talks 2 DGP Meeting September 5-9, 2012 Plant nutrition in a changing environment. Patrick H. Brown Department of Plant Sciences, University of California, Davis, CA 95616, US; E-mail: [email protected] The scientific discipline of plant nutrition is wonderfully broad in its scale and its scope. From the exploration of the function of nutrients as signals and regulators of plant function, to the role of plant nutrients in agricultural productivity and food quality, to the exploration of the effects of nutrient losses on global environments, plant nutrition is a truly integrative discipline and will play a critical role in mans’ ability to adapt to environmental change. Plant nutrition is by design a multi-scale endeavor embracing science from the most fundamental principle to the grandest policy decisions. Thus the term ‘changing environments’ is equally broad in its implications and would include: 1) the explicit changes in the climate that affect plant nutrient relations (CO 2 enrichment, temperature shifts, altered biotic and abiotic stresses), 2) the growing public demand for better environmental stewardship, 3) the need for higher food quality, 4) a recognition of the challenges of diminishing nutrient resources and growing competition for those limited resources, 5) the changing nature of research funding and the loss of support for adaptive and translational research and 6) the changing manner in which agricultural producers and policy makers get their information and make their decisions. As plant nutritionists we clearly find ourselves in a changing environment. Understanding how the various aspects of this changing environment impact upon the field of plant nutrition will inform how we focus our efforts, and how we adapt and extend our research to our colleagues, to agricultural producers, to governments and policy makers and ultimately will determine how ‘useful’ our contributions will be. These issues will be discussed with examples drawn from the literature and from experiences in California and Australia. 3 DGP Meeting September 5-9, 2012 The mineral nutrition of plants and people Philip J. White The James Hutton Institute, Dundee, UK; E-mail: [email protected] Food security is defined as having sufficient, safe and nutritious food to meet the dietary needs of an active and healthy life. This presentation describes the role of plant mineral nutrition in crop production and dietary delivery of mineral elements essential to human wellbeing. Plants require at least 14 mineral elements. Fertilisers containing these elements are often applied to crops to maximise yields. However, the application of fertilisers has both economic and environmental costs. Research on agronomic strategies to improve the efficiency of fertiliser use by crops and genetic approaches to develop crops with improved acquisition and physiological use of mineral elements will be presented. Ultimately, plants provide humans with their minerals. Unfortunately, the diets of over 60% of the world’s population lack essential mineral elements. The concentrations of mineral elements in edible crops can be increased through either agronomic or genetic approaches. Soil or foliar fertilisers can be used to biofortify edible crops with, for example, iodine, selenium, iron and zinc. In addition, if the mineral element is present in the soil, crops can be developed for greater acquisition and accumulation in edible portions. Examples of the variation in mineral composition of edible crops will be given and the potential of crop genetics to deliver varieties to improve the mineral nutrition of humans will be discussed. 4 DGP Meeting September 5-9, 2012 Plenary Session S1: Processes on leaf surfaces 5 DGP Meeting September 5-9, 2012 Functions of and processes on leaf surfaces Markus Riederer Julius-von-Sachs-Institut für Biowissenschaften, University of Würzburg, Julius-von-Sachs-Platz 3, Würzburg, Germany; E-mail: [email protected] 6 DGP Meeting September 5-9, 2012 Foliar fertilization of crops Victoria Fernández Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain; Email: [email protected] Foliar fertilisation is an increasingly-used agricultural practice which may help to increase crop yields and quality while contributing to a rational use of fertilizers when applied in combination with soil treatments. However, many factors influencing the effectiveness of foliar sprays and the process of foliar uptake and translocation remain unclear, which hinders the development of reliable foliar fertilization strategies and may lead to variable plant responses to the treatments. In the course of this presentation the current state of knowledge on foliar nutrient sprays will be revised within a physiological, physico-chemical and agronomic context, focusing on the constrains and opportunities of applying nutrients to crop plants via the foliage. 7 DGP Meeting September 5-9, 2012 The role of stomata in foliar fertilization Thomas Eichert University of Bonn, Institute of Crop Science and Resource Conservation (INRES), Dept. of Plant Nutrition, Karlrobert-Kreiten-Str. 13, D 53115 Bonn, Germany; E-mail: [email protected] Foliar fertilization is a common practice to quickly correct nutrient deficiencies, especially under conditions of limited soil nutrient availability. For a long time it was assumed that foliar nutrient uptake is restricted to the cuticle, while stomata were supposed to be impermeable to foliar-applied solutes. In our studies we found evidence that this paradigm needs to be revised (Fernández and Eichert 2009, Eichert and Fernández 2012). Our results indicate that solute uptake through stomata is in fact possible (Eichert and Burkhardt 2001) and that the stomatal penetration pathway can be as important as the cuticular pathway (Eichert and Goldbach 2008). Experiments using N compounds or nm-particles showed that the stomatal pathway enables penetration of substances as large as 40 nm (Eichert and Goldbach 2008, Eichert et al. 2008) whereas our estimations of pore sizes in cuticles of stomata-free, intact leaves yielded diameters of 4-5 nm (Eichert and Goldbach 2008). These results are in accordance with field observations that large molecules (e.g., Fe-chelates) can penetrate stomata-free upper leaf surfaces and that uptake rates of mineral nutrients are frequently larger through the stomata-bearing lower leaf surface than through the upper surface. References Eichert T, Burkhardt J (2001) Quantification of stomatal uptake of ionic solutes using a new model system. Journal of Experimental Botany 52: 771-781. Eichert T, Fernández V (2012) Uptake and Release of Mineral Elements by Leaves and Other Aerial Plant Parts. In: Marschner’s Mineral Nutrition of Higher Plants, 3rd edition, Academic Press, pp. 71-84 Eichert T, Goldbach HE (2008) Equivalent pore radii of hydrophilic foliar uptake routes in stomatous and astomatous leaf surfaces – further evidence for a stomatal pathway. Physiologia Plantarum 132: 491–502. Eichert T, Kurtz A, Steiner U, Goldbach HE (2008) Size exclusion limits and lateral heterogeneity of the stomatal foliar uptake pathway for aqueous solutes and water-suspended nanoparticles. Physiologia Plantarum 134: 151–160. Fernández V, Eichert, T (2009) Uptake of hydrophilic solutes through plant leaves: current state of knowledge and perspectives of foliar fertilization. Critical Reviews in Plant Sciences 28: 36-68 8 DGP Meeting September 5-9, 2012 Biofortification of field vegetables with iodine: efficiency of soil and foliar fertilization techniques Patrick Lawson, Roman Czauderna and Diemo Daum University of Applied Sciences Osnabrück, Faculty of Agricultural Science and Landscape Architecture E-mail: [email protected] Introduction Iodine is an essential trace element for the synthesis of thyroid hormones in the human body. An inadequate dietary iodine intake has certain negative effects on human health. According to the World Health Organization almost 2 billion individuals worldwide are currently affected by iodine deficiency (De Benoist et al. 2009). Although
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