Precision weed control in sunflower and maize - experiences from Hungary

In recent years, a Hungarian private farm in Zimany (Southern Hungary) systematically built-up and developed its spatial information infrastructure and enabled us to carry out research on and development of site-specific weed management methods. Over the past four years, our goals were to improve weed control efficacy and to reduce the amount of herbicides applied. We a) developed an off-line, map-based method for pre-emergent precision herbicide treatments to control weeds in maize and sunflower (our application algorithm is based on the humus content and an empirical plasticity index of the soil), and b) in on-line precision post-emergent inrow treatments in maize we used a novel approach to mount mechanically shielded WeedSeeker (NTech Industries) sensor-sprayers on a precision cultivator (Garford Farm Machinery) in order to apply a non-selective (total) herbicide (glyphosate) safely under the leaf canopy. Keywords: GPS, herbicides, precision agriculture, sensor-sprayers, site-specific weed management Präzise Unkrautkontrolle in Sonnenblume und Mais - Erfahrungen aus UngarnIn den letzten Jahren hat ein privater landwirtschaftlicher Betrieb in Zimány (Südungarn) seine räumliche Geoinformations-Infrastruktur deutlich verbessert und die Durchführung der Forschung und Entwicklung von Methoden zur teilflächenspezifischen Unkrautmanagement ermöglicht. In den letzten vier Jahren entwickelten wir eine kartenbasierte Methode (Off-line) für a) Vorauflauf- Präzisionsherbizidbehandlungen in Mais und Sonnenblumen (der angewendete Algorithmus basiert auf dem Humus- und Sandgehalt des Bodens) und für b) Nachauflauf- Präzisionsherbizidanwendungen in Reihen-Kulturen, die eine zwei-Komponenten- Herbizidkombination mit variabler Zusammensetzung verwendet (die Dosis und der Anteil der Herbizide ist dichtebasiert). In Online-Präzisionsbehandlungen für Nachauflauf-Unkraut in Mais haben wir WeedSeeker (NTech Industries, USA) Sprühgeräte verwendet, um die Herbizide unter dem Blätterdach anzuwenden. Stichwörter: GPS, ortsspezifische Unkrautbekämpfung, teilflächenspezifische Landwirtschaf

Preface to the first issue of Ecocycles

On behalf of the Committee of the European Ecocycles Society (ECyS) we are pleased to announce the publication of the inaugural issue of Ecocycles, our Society’s scientific journal. Ecocycles has been many months in the making: the Committee of ECyS became aware of the wide interest in the subject during the foundation of the Society and felt that a committed journal would be able to bring together the ideas of a broad academic community

Importance of plant virus research - a brief revisit

In this paper, we wish to comment on a recent essay on virus research that was published in The Economist (August 20, 2020). The essay is so well-written and informative that it serves as an excellent example of popularizing science to make it accessible to all segments of an inquiring society. Still, we would like to point out that the paper failed to cover one important area of virus research: the fundamental discoveries achieved by studies of the viruses of higher plants

Importance of nickel as a micronutrient in aquaponic systems : some theoretical considerations

This Note paper calls the attention to the important role the microelement nickel plays is the decomposition of urea in aquaponic systems. Since fish feeds do not contain nickel (it is not included in the list of micronutrients essential to fish growth and development) trace amounts of its soluble salts or complexes need to be added to aquaponic systems in order to achieve the systems' stable operation

Phytoremediation of persistent organic pollutants

Toxicity, chemical stability, bioaccumulation, and long-range transport of persistent organic pollutants (POPs) cause environmental and human health hazards, and demand the cleanup of remnants from previous applications. Phytoremediation uses living higher plants for the removal and biochemical decomposition of environmental pollutants and became a front-runner among cleanup technologies. The efficiency of plants as detoxifiers, filters or traps has been proven in cleaning up soils polluted with crude oil, explosives, landfill leachates, metals, pesticides, and solvents. Although phytoremediation of POPs is made very difficult by their low bioavailability, recent literature indicated that some plants (primarily those belonging to the Cucurbitaceae family) are capable of taking up significant amounts of POPs and accumulate them in their tissues. A joint French-Hungarian research project will investigate the possibility of phytoremediation of POP

Human geography of drylands. I. Planning the database: Physical, built-up, chemical, biological (ecological), and social indicators

We propose a method based on multilayered mapping for investigating the current problems of people who live in drylands and we urge decision-makers to support such studies to establish the foundations for future decisive and preventive actions. This paper contains an expandable compilation of the environmental indicators (mostly mappable) that may influence the human geography of a certain region. We believe that this geospatial approach may help to resolve convoluted physical, chemical, and social relation­ships and, at the same time, generate a valuable database for further research. The application of the concept, if successful, will give directions to tackle certain contem­porary problems in drylands and predict future ones caused by global climate change

Glutathione S-Transferase Enzymes in Plant-Pathogen Interactions

Plant glutathione S-transferases (GSTs) are ubiquitous and multifunctional enzymes encoded by large gene families. A characteristic feature of GST genes is their high inducibility by a wide range of stress conditions including biotic stress. Early studies on the role of GSTs in plant biotic stress showed that certain GST genes are specifically up-regulated by microbial infections. Later numerous transcriptome-wide investigations proved that distinct groups of GSTs are markedly induced in the early phase of bacterial, fungal and viral infections. Proteomic investigations also confirmed the accumulation of multiple GST proteins in infected plants. Furthermore, functional studies revealed that overexpression or silencing of specific GSTs can markedly modify disease symptoms and also pathogen multiplication rates. However, very limited information is available about the exact metabolic functions of disease-induced GST isoenzymes and about their endogenous substrates. The already recognized roles of GSTs are the detoxification of toxic substances by their conjugation with glutathione, the attenuation of oxidative stress and the participation in hormone transport. Some GSTs display glutathione peroxidase activity and these GSTs can detoxify toxic lipid hydroperoxides that accumulate during infections. GSTs can also possess ligandin functions and participate in the intracellular transport of auxins. Notably, the expression of multiple GSTs is massively activated by salicylic acid and some GST enzymes were demonstrated to be receptor proteins of salicylic acid. Furthermore, induction of GST genes or elevated GST activities have often been observed in plants treated with beneficial microbes (bacteria and fungi) that induce a systemic resistance response (ISR) to subsequent pathogen infections. Further research is needed to reveal the exact metabolic functions of GST isoenzymes in infected plants and to understand their contribution to disease resistance

Extension of aquaponic water use for NFT baby-leaf production : mizuna and rocket salad

Aquaponics is a recirculating technology that combines aquaculture with hydroponics. It allows nutrients from fish waste to feed plants and thus saves water and nutrients. However, there is a mismatch between the nutrients provided by the fish waste and plant needs. Because of this, some nutrients, notably N, tend to accumulate in the aquaponic water (APW or AP water). The aim of this study was to investigate how APW, which is depleted of P and K but still rich in N, could be further utilized. APW was used in a mesocosm and compared with APW from the same source that had been supplemented with macro-nutrients (complemented AP water or CAPW) and a hydroponic control (HC). Mizuna (M) and rocket salad (R) were used as short-cycle vegetable crops in a NFT system. The results revealed that the low production potential of APW was mainly caused by the lack of P and K. If these were supplemented, the yields were comparable to those in the HC. M yield in CAPW was significantly higher than that of HC, probably due to biostimulant effects connected to the organic components in the water as a result of fish farming. Water type, cultivation density, and intercropping significantly influenced the qualitative characteristics of the crop in terms of antioxidant compounds and minerals. Nitrate content in vegetables was lower than European regulation limits. The extended use of APW is viable if the missing nutrients are supplemented; this could be a strategy to increase the efficiency of water and nitrogen use, while further reducing environmental impact

Vegetable intercropping in a small-scale aquaponic system

This paper reports the results of the first study of an aquaponic system for Pangasianodon hypophthalmus production that uses Lactuca sativa L. (lettuce) and Cichorium intybus L. rubifolium group (red chicory) intercropping in the hydroponic section. The experiment was conducted in a greenhouse at the Zurich University of Applied Sciences, W\ue4denswil, Switzerland, using nine small-scale aquaponic systems (each approximately 400 L), with the nutrient film technique (NFT). The intercropping of vegetables did not influence the water temperature, pH, electric conductivity (EC), oxidation\u2013reduction potential, nor O2 content. Intercropping with red chicory increased the lettuce sugar content (+16.0% and +25.3% for glucose and fructose, respectively) and reduced the lettuce caffeic acid content ( 1216.8%). In regards to bitter taste compounds (sesquiterpene lactones), intercropping reduced the concentrations of dihydro-lactucopicrin + lactucopicrin ( 1242.0%) in lettuce, and dihydro-lactucopicrin + lactucopicrin ( 1222.0%) and 8-deoxy\u2013lactucin + dihydro-lactucopicrin oxalate ( 1218.7%) in red chicory, whereas dihydro-lactucin content increased (+40.6%) in red chicory in regards to monoculture. A significantly higher organic nitrogen content was found in the lettuce (3.9%) than in the red chicory biomass (3.4%), following the intercropping treatment. Anion and cation contents in vegetables were affected by species (Cl 12, NO3 12, PO43 12, SO42 12, and Ca2+), intercropping (K+ and Mg2+), and species 7 intercropping interactions (NO2 12 and NH4+). Experimental treatments (monoculture vs intercropping and distance from NFT inlet) did not exert significant effects on leaf SPAD (index of relative chlorophyll content) values, whereas the red coloration of the plants increased from the inlet to the outlet of the NFT channel. Intercropping of lettuce and red chicory affected the typical taste of these vegetables by increasing the sweetness of lettuce and changing the ratio among bitter taste compounds in red chicory. These results suggest intercropping as a possible solution for improving vegetable quality in aquaponics. Although the results are interesting, they have been obtained in a relatively short period, thus investigations for longer periods are necessary to confirm these findings. Further studies are also needed to corroborate the positive effect of the presence of red chicory in the system on fish production parameters

On the sustainability of aquaponics

Aquaponics is an evolving closed-system food production technology that integrates recirculating aquaculture with hydroponics. In this paper we give a brief literature overview of the sustainability aspects of aquaponics by discussing its social, environmental, and economic impacts in different potential settings. The technology might be applied to commercial or community based urban food production, industrial scale production in rural areas, small scale farming in developing countries or as systems for education and decoration inside buildings. We conclude that due to the different potential applications and settings for installing the technology, sustainability impacts need to be considered separately and that due the complexity within markets, value chains, communities, urban and rural infrastructure and policy settings, further research and data acquisition is needed to be able to assess all sustainability aspects