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Definition of common urban agriculture terms in German language and English equivalents
Get PDFDie Integration landwirtschaftlicher Aktivitäten in Stadtentwicklungskonzepte und die Planung der produktiven grünen Infrastruktur im urbanen Raum erfordert eine räumliche und inhaltliche Definition des Begriffs der „urbanen Landwirtschaft“. Auf der Grundlage existierender Begrifflichkeiten haben sich hier die Bundesforschungseinrichtungen aus dem Geschäftsbereich des Bundesministeriums für Ernährung und Landwirtschaft auf eine für sie verbindliche Definition geeinigt. Die urbane Landwirtschaft umfasst danach alle Produktionssysteme und -verfahren der Landwirtschaft im weitesten Sinn, die auf Flächen, in Gewässern oder auf, an oder in Gebäuden in der Stadt oder ihrem nahen Umfeld für die kommerzielle oder nicht-kommerzielle Erzeugung von Produkten und Leistungen einschließlich Ökosystemleistungen im stadtregionalen, d. h. stadtnahem ruralem, peri-urbanen und intra-urbanen Raum genutzt werden. Zusätzlich wird ein Glossar von gebräuchlichen Begriffen der urbanen Landwirtschaft vorgeschlagen.The integration of agricultural activities into urban development concepts and the planning of productive green infrastructure in urban areas requires a comprehensive definition of the term "urban agriculture". On the basis of existing terminology, the federal research institutions of the German Federal Ministry of Food and Agriculture have agreed on a definition that is binding for them. According to this, urban agriculture includes all agricultural production systems and processes in the broadest sense that are used on land, in or on water bodies, in or on buildings in the city or its immediate vicinity for the commercial or non-commercial production of products and services including ecosystem services in the city-regional, i.e. city-near rural, peri -urban and intra-urban space. A complementary bilingual glossary of urban agricultural nomenclature is provided
Ecophysiological responses of grapevine rootstocks to water deficit
Get PDFThe use of rootstocks tolerant to soil water deficit is an interesting strategy to face the challenges posed by limited water availability. Currently, several nurseries are breeding new genotypes aiming to improve the water stress tolerance of grapevine, but the physiological basis of its responses under water stress are largely unknown. For this purpose, an ecophysiological assessment of the conventional 110-Richter (110R) and SO4, and the new M1 and M4 rootstocks was carried out in ungrafted potted plants. During one season, these Vitis genotypes were grown under greenhouse conditions and subjected to two water regimes, well-watered (WW) and deficit irrigation (DI). Water potentials of plants under DI down to <-1.4 MPa, and net photosynthesis (AN) <5 μmol CO2m-2s-1 did not cause leaf oxidative stress damage compared to WW conditions in all genotypes. The antioxidant capacity was sufficient to neutralize the mild oxidative stress suffered. Under both water regimes, gravimetric differences in daily water use were observed among genotypes, leading to differences in the biomass of roots and shoots. Under WW conditions, SO4 and 110R were the most vigorous and M1 and M4 the least. However, under DI, SO4 exhibited the greatest reduction in biomass, while 110R showed the lowest. Remarkably, under these conditions, SO4 reached the least negative stem water potential and showed the highest hydraulic conductance values. Conversely, M1 reduced the most stomatal conductance, transpiration and AN. Overall, 110R achieved the highest biomass water use efficiency in response to DI, and SO4 the lowest, while M-rootstocks showed intermediate values. Our results suggest that there are differences in water use regulation among genotypes attributed not only to differences in stomatal regulation but also to plant hydraulic conductance. Therefore, it is hypothesized that differences in genotype performance may be due to root anatomical- morphological differences and to several physiological processes such as growth inhibition, osmotic adjustment, antioxidant production, nutrient translocation capacity, etc. Further studies are needed to confirm these differential ecophysiological responses of Vitis species under water stress, particularly under field and grafted conditions
Is vigour-based length adjustment during permanent cordon establishment a beneficial practice?
Get PDFLow vigour canes selected for the establishment of permanent cordon arms may lack the sufficient vigour required for uniform bud burst and growth of new shoots following cordon training. This may lead to stunted or missing spur positions, particularly in the middle of new cordon arms where the effect is most pronounced due to the prioritisation tendencies of the vine, including apical dominance and acrotony. A trial was performed to investigate the benefits of adjusting the length of newly trained canes intended as permanent cordon arms during their establishment to limit their bud number and guide new growth. This length adjustment was based on an assessment of the apparent vigour of selected canes and was performed at the start of the first season of cordon growth, with cordons then extended to their final length. The trial did not yield results indicating a long-term beneficial response to this practice, with physiological measurements including pruning weight showing no difference between length adjusted and control vines in the later seasons of the trial. There was also a lower plant area index (PAI), and higher canopy porosity (Φ) observed in length adjusted vines compared to control vines at several points. There was no difference observed in circumference measures of the distal portion of arms which had undergone a length adjustment, suggesting that the exercise did not have an adverse impact on their capacity for transport and reserve storage. Harvest yield components did not vary with treatment; however, a significantly lower pH was observed in length adjusted vines compared to control vines in the trial\u27s final season. Further research could help to provide more insight into the benefits of this practice, as some results from the trial, including a significantly higher pruning weight, cane number, and cane weight observed in the intermediate sections of cordon arms during the first season of growth suggest that it may have been of some aid to the cordons on which it was implemented
Genetic diversity and virulence variability in Diplodia mutila isolates from symptomatic grapevines in New Zealand: Virulence and genetic diversity of Diplodia mutila
Get PDFGenetic diversity and virulence variability of Diplodia mutila isolates recovered from grapevines in New Zealand were investigated. The universally primed PCR (UP-PCR) and vegetative compatibility group (VCG) methods were used to investigate the genetic diversity. Pathogenicity tests with ‘Sauvignon Blanc’ detached shoots and potted vines were used to determine the virulence diversity. UP-PCR analysis determined eight genetic groups of D. mutila with 70% of the population within one group. Phylogenetic analysis also determined that New Zealand isolates were more closely related to Australian isolates than Californian isolates. Vegetative compatibility grouping analysis placed the isolates into three VCG groups, with 57% of isolates belonging to all three VCGs. Vegetative compatibility reactions were observed among isolates, but this was not correlated with the genetic clustering. Virulence assays proved that all isolates tested were pathogenic on grapevine stems. Differences in necrotic lesions lengths caused by D. mutila isolates were identified, indicating different virulence levels among isolates, however, no relationship was found between the genetic groups and the virulence. The results of the study indicated movement of D. mutila isolates between nurseries, vineyards, and other sources in New Zealand. This information will inform control strategies to limit the further spread of this pathogen into vineyards in the same region or new regions
Diversity and distribution of Diplodia spp. – causative agent of black canker on pome fruit trees – in Germany
Get PDFDer Schwarze Rindenbrand, der von Pilzen aus der Gattung Diplodia hervorgerufen wird, stellt eine zunehmende Bedrohung für den Kernobstanbau in Deutschland dar. Um die Verbreitung der Erkrankung im Bundesgebiet zu ermitteln, wurden in einem nicht repräsentativen Monitoring 423 Rindenproben mit verdächtigen Symptomen aus allen Bundesländern untersucht. In 62 % der untersuchten Proben waren Pilze aus der Gattung Diplodia zu isolieren, wobei die Art D. bulgarica mit 56,6 %, gefolgt von D. seriata mit 28,3 % das Diplodia-Artenspektrum dominiert haben. D. malorum (7,8 %), D. mutila (4,9 %), D. juglandis (1,6 %) und D. intermedia (0,8 %) traten dagegen relativ selten auf, wobei die beiden letztgenannten Arten Erstnachweise an Apfel in Deutschland sind.Black canker, caused by fungi of the genus Diplodia, poses an increasing threat to pome fruit production in Germany. In order to determine the spread of the disease in Germany, 423 bark samples with suspicious symptoms from all federal states were examined in a non-representative monitoring. In 62% of the samples examined, fungi of the genus Diplodia were isolated, with the species D. bulgarica dominating the Diplodia species spectrum with 56.6%, followed by D. seriata with 28.3%. D. malorum (7.8%), D. mutila (4.9%), D. juglandis (1.6%) and D. intermedia (0.8%), on the other hand, took up only a small part of the Diplodia species spectrum, with the latter two species being first records on apple in Germany
