50 research outputs found
LEAF AREA INDEX IN WINTER WHEAT: RESPONSE ON SEED RATE AND NITROGEN APPLICATION BY DIFFERENT VARIETIES
The most important photosynthesis acceptor – leaf area vary among cultivation measures and it is limited factor for creating exact growth models in common winter wheat. The objective of this study was to investigate changes of leaf area index (LAI) affected by agricultural treatments – 4 sowing rates and 9 nitrogen treatments based on fertilising rates, target values based on soil mineral nitrogen and plant sap tests target values including different varieties. Increasing sowing rates from 350 to 800 viable seeds m-2 increased LAI at EC 75 stage from 2.9 to 5.5, where LAI 4.1 at 500 seeds m-2 did not vary between lower and higher rates; also at EC 85 stage LAIs did not differ significantly. At EC 75 stage LAI differed among control and nitrogen treatments from 1.0 to 6.5 and at EC 85 stage from 0.1 to 2.4, with differences in interaction among varieties. Higher nitrogen rates for first and second top dressing increased LAI in both stages compared without dressing treatments. Due to significant differences among LAI as consequence of production system, we suggest to take this into account in every prediction and modelling of growth in winter wheat.Listna površina, kot najpomembnejši fotosintetski akceptor je odvisna od pridelovalnih ukrepov in je omejitveni dejavnik za izdelavo natančnih rastnih modelov navadne ozimne pšenice. Cilj te študije je preveriti spremembe indeksa listne površine (LAI) pod vplivom agrotehničnih ukrepov – 4 gostot setve, 9 odmerkov dušika temelječih na odmerkih gnojil in temelječih na ciljnih vrednostih Nmin-a ter hitrih nitratnih rastlinskih testov vključujoč različne sorte. Povečevanje setvene norme od 350 do 800 kalivih semen m-2 povečuje LAI v fazi EC 75 od 2.9 do 5.5, medtem ko med njima in 500 kalivimi zrni m-2 značilnih razlik med LAI ni bilo; tudi v fazi EC 85 med LAI nismo ugotovili značilnih razlik. V fazi EC 75 je LAI variral od 1.0 v kontrolnem obravnavanju do 6.5 v gnojilnih obravnavanjih, v fazi EC 85 pa od 0.1 do 2.4, s tem da so bile značilne razlike tudi v interakciji s sortami. Višji odmerki dušika za
prvo in drugo dognojevanje povečujejo LAI v obeh fazah v primerjavi z obravnavanji brez dognojevanja. Zaradi značilnih razlik med LAI kot posledica agrotehnike, priporočamo upoštevati razlike med LAI pri vsakem načrtovanju ali modeliranju rasti ozimne pšenice
Bilan et perspectives de la Recherche en Agriculture Bio-dynamique
L’Agriculture Biodynamique (BD) a été l’objet de nombreux efforts de recherches durant les dernières décennies, bien qu’une partie de la communauté scientifique regarde les méthodes biodynamiques avec scepticisme et les considère comme dogmatiques. Néanmoins, comme cela est montré dans cet article de synthèse, une part non négligeable des résultats présentés dans des revues scientifiques à comité de lecture et issus d’expérimentations contrôlées de plein champ, ou d’étude de cas, montrent des effets des préparations biodynamiques sur le rendement, la qualité du sol et la biodiversité. De plus, les préparations biodynamiques ont un impact environnemental positif en termes d’utilisation et d’efficacité énergétique. Cependant, le mode d’action mécanique des préparations biodynamique est toujours en cours d’investigation en sciences naturelles. Par ailleurs, les méthodes d’évaluations de la qualité basées sur des approches globales (holistiques) sont de plus en plus étudiées et reconnues. L’agriculture BD s’efforce également, comme cela est montré dans plusieurs publications, d’influencer positivement le paysage culturel. La synthèse des données montre le besoin de poursuivre les recherches dans le domaine de la qualité des aliments, de la sécurité alimentaire, des performances environnementales (par ex. l’empreinte écologique), et sur l’influences des pratiques BD sur les animaux d’élevage
EFFECT OF AN IN-SEASON LIVING MULCH ON LEACHING OF INORGANIC NITROGEN IN CAULIFLOWER (BRASSICA OLERACEA L. VAR. BOTRYTIS) CROPPING IN SLOVENIA, GERMANY AND DENMARK
Vegetables with a high nitrogen demand such as cauliflower may cause intensive leaching of nitrate to the environment in conventional as well as in organic production. In organic cropping systems, the use of an in-season living mulch may decrease the risk of nitrate leaching after harvest when left growing in the field to the end of the leaching season in spring. The aim of this study was to investigate the effect of growing an in-season living mulch including legumes on the risk of leaching of inorganic nitrogen over winter, and soil nitrogen availability the following spring. Three field experiments were carried out in Slovenia, Germany and Denmark in the frame of the Interveg project (CORE organic II). Evaluation of soil inorganic nitrogen content was done at planting, at harvest, in late autumn and in spring to a depth of 0.6, 0.9 or 1.5 m as well as nitrogen uptake by the biomass. This study reports preliminary results of the first year of experiments on soil inorganic nitrogen at harvest and the end of the leaching season. They indicate that living mulches may have a potential to decrease the nitrate leaching risk depending on the design of the cropping system
Can new organic cropping systems produce vegetables with lower use of resources and losses of nitrate?
To secure a sustainable production of plant foods for the future, there is a need to develop new cropping systems. These systems should have reduced needs of external resources and reduced environmental impact, while product yields are maintained at high level. Therefore, field trials were performed in Italy, Slovenia, Germany and Denmark with the aim to study new organic cropping systems for production of vegetable crops; and the systems’ effect on labor and energy consumption and the risk of losing nitrate to the water environment. The cropping systems included an in-season living mulch to exploit ecosystem services by attracting beneficial insects, suppressing weeds, and taking up excess nitrogen during production of two high-value crops of leek and cauliflower. The first year results show that high yields and quality were maintained if the living mulches were properly managed e.g. by sowing date or root pruning to control plant competition. The systems including living mulches changed the costs from +22 to -2% and total energy consumption from +14 to -4% compared to sole cropping depending on the change of management techniques in each country. The proportion between human power and fossil fuel consumption was changed. The risk of nitrate leaching was affected to a minor degree depending on the spatial layout of living mulch and crop rows. The study indicates that new cropping systems can be developed based on in-season living mulches for organic production with high yields, weed suppression and reduction of the risk of nitrate leaching. However, the management of the living mulches in terms of machinery, agronomic techniques and timing needs to be developed to optimize outcomes for food security, energy use and environmental impact. The study is part of the INTERVEG project
Quaternary glacial history of the Mediterranean mountains
Glacial and periglacial landforms are widespread in the mountains of the Mediterranean region. The evidence for glacial and periglacial activity has been studied for over 120 years and it is possible to identify three phases of development in this area of research. First, a pioneer phase characterized by initial descriptive observations of glacial landforms; second, a mapping phase whereby the detailed distribution of glacial landforms and sediments have been depicted on geomorphological maps; and, third, an advanced phase characterized by detailed understanding of the geochronology of glacial sequences using radiometric dating alongside detailed sedimentological and stratigraphical analyses. It is only relatively recently that studies of glaciated mountain terrains in the Mediterranean region have reached an advanced phase and it is now clear from radiometric dating programmes that the Mediterranean mountains have been glaciated during multiple glacial cycles. The most extensive phases of glaciation appear to have occurred during the Middle Pleistocene. This represents a major shift from earlier work whereby many glacial sequences were assumed to have formed during the last cold stage. Glacial and periglacial deposits from multiple Quaternary cold stages constitute a valuable palaeoclimatic record. This is especially so in the Mediterranean mountains, since mountain glaciers in this latitudinal zone would have been particularly sensitive to changes in the global climate system. © 2006 Edward Arnold (Publishers) Ltd
Effect of planting density on green ear yield of maize cultivars bred in different periods
Relationship between SPAD value and grain yield can be affected by cultivar, environment and soil nitrogen content in wheat
Liraglutide modulates GABAergic signaling in rat hippocampal CA3 pyramidal neurons predominantly by presynaptic mechanism
ALTERNATIVNI POLJSKI USJEVI KAO EKOLOŠKI PROIZVODI PREGLED ISTRAŽIVAČKIH I RAZVOJNIH AKTIVNOSTI U SLOVENIJI
Introduction, production and marketing in alternative (underutilized, neglected, disregarded, rare) crops is a very complex system, but very helpful for producers and consumers. Based on eighteen years of Slovenian experiences since establishment of certification of organic agriculture, research on under-utilized field crops and publisi materials we can conclude that many additional activities are needed to establishing an effective production system and market for underutilized field crops. Primari, high by efficient organic production must follow professional knowledge of production, guidelines for organic production and post harvest technology including food processing. Special attention must be paid to production of introduced species in the region. For example, our research project on four oil crops grown under dry conditions, including greenhouse experiments is a contribution to how to include less sensitive crops into rotation systems because of climate changes. Activities such as expansion of the knowledge on organic products, and especially about nutritional and health value of crops are very important. Organizing projects why and how to use this kind of food in the kindergartens, schools, old people’s homes and hospitals shows promising results, especially when the culinary presentation includes explanation of beneficial effects on human health. On the other side the useful research is obligatory; for example an explanation how to prepare tasty and highly essential amino-acid valued bread made from grain amaranth and whole meal spelt. Also the models for decission support are developed, but due to the lack of data, their use is not often in accordance with the needs in practice.Uvođenje, proizvodnja i prodaja alternativnih (zapostavljenih) usjeva je vrlo složen, ali i vrlo koristan proces za proizvođača i za potrošača. Na temelju osamnaestogodišnjeg slovenskog iskustva od pokretanja i certificiranja ekološke poljoprivrede, istraživanja malo korištenih poljskih usjeva i publiciranih radova možemo zaključiti da su potrebne još mnoge dodatne aktivnosti kako bi se uspostavio efikasan proizvodni sistem i tržište za nedovoljno korištene poljske usjeve. Visoko učinkovita ekološka proizvodnja treba se temeljiti na stručnom znanju o tehnologiji proizvodnje, stručnim uputama, te tehnologijama spremanja i prerade uroda nakon žetve. Posebnu pažnju traži proizvodni sistem za svaku novouvedenu vrstu usjeva u određenom uzgojnom području. Npr. naš projekt istraživanja uzgoja četiriju uljarica u uvjetima suše, uključujući pokuse u stakleniku, prilog je uključivanju u proizvodnju manje osjetljivih usjeva – vezano uz klimatske promjene. Od posebne je važnosti širenje znanja o ekološkoj proizvodnji, posebno o nutritivnoj i zdravstvenoj vrijednosti takvih proizvoda. Projekti s ciljem uključivanja ekoloških proizvoda u dječje vrtiće, škole, staračke domove i bolnice dali su obećavajuće rezultate, posebno ako su kulinarske prezentacije bile praćene isticanjem pozitivnog učinka na zdravlje. S druge strane neophodna su korisna istraživanja, npr. kako načiniti hranidbeno visokovrijedan (bogat esencijalnim aminokiselinama) i ukusan kruh od štira i cjelovitog brašna krupnika (T. spelta). Također, razvijen je model podrške u donošenju odluke, no zbog nedostatka podataka, njegovo korištenje nije u skladu s potrebama u praksi
ALTERNATIVNI POLJSKI USJEVI KAO EKOLOŠKI PROIZVODI PREGLED ISTRAŽIVAČKIH I RAZVOJNIH AKTIVNOSTI U SLOVENIJI
Introduction, production and marketing in alternative (underutilized, neglected, disregarded, rare) crops is a very complex system, but very helpful for producers and consumers. Based on eighteen years of Slovenian experiences since establishment of certification of organic agriculture, research on under-utilized field crops and publisi materials we can conclude that many additional activities are needed to establishing an effective production system and market for underutilized field crops. Primari, high by efficient organic production must follow professional knowledge of production, guidelines for organic production and post harvest technology including food processing. Special attention must be paid to production of introduced species in the region. For example, our research project on four oil crops grown under dry conditions, including greenhouse experiments is a contribution to how to include less sensitive crops into rotation systems because of climate changes. Activities such as expansion of the knowledge on organic products, and especially about nutritional and health value of crops are very important. Organizing projects why and how to use this kind of food in the kindergartens, schools, old people’s homes and hospitals shows promising results, especially when the culinary presentation includes explanation of beneficial effects on human health. On the other side the useful research is obligatory; for example an explanation how to prepare tasty and highly essential amino-acid valued bread made from grain amaranth and whole meal spelt. Also the models for decission support are developed, but due to the lack of data, their use is not often in accordance with the needs in practice.Uvođenje, proizvodnja i prodaja alternativnih (zapostavljenih) usjeva je vrlo složen, ali i vrlo koristan proces za proizvođača i za potrošača. Na temelju osamnaestogodišnjeg slovenskog iskustva od pokretanja i certificiranja ekološke poljoprivrede, istraživanja malo korištenih poljskih usjeva i publiciranih radova možemo zaključiti da su potrebne još mnoge dodatne aktivnosti kako bi se uspostavio efikasan proizvodni sistem i tržište za nedovoljno korištene poljske usjeve. Visoko učinkovita ekološka proizvodnja treba se temeljiti na stručnom znanju o tehnologiji proizvodnje, stručnim uputama, te tehnologijama spremanja i prerade uroda nakon žetve. Posebnu pažnju traži proizvodni sistem za svaku novouvedenu vrstu usjeva u određenom uzgojnom području. Npr. naš projekt istraživanja uzgoja četiriju uljarica u uvjetima suše, uključujući pokuse u stakleniku, prilog je uključivanju u proizvodnju manje osjetljivih usjeva – vezano uz klimatske promjene. Od posebne je važnosti širenje znanja o ekološkoj proizvodnji, posebno o nutritivnoj i zdravstvenoj vrijednosti takvih proizvoda. Projekti s ciljem uključivanja ekoloških proizvoda u dječje vrtiće, škole, staračke domove i bolnice dali su obećavajuće rezultate, posebno ako su kulinarske prezentacije bile praćene isticanjem pozitivnog učinka na zdravlje. S druge strane neophodna su korisna istraživanja, npr. kako načiniti hranidbeno visokovrijedan (bogat esencijalnim aminokiselinama) i ukusan kruh od štira i cjelovitog brašna krupnika (T. spelta). Također, razvijen je model podrške u donošenju odluke, no zbog nedostatka podataka, njegovo korištenje nije u skladu s potrebama u praksi