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Key performance indicators and economic assessment of site-specific pesticide applications with direct injection and application assistance system
Get PDFTeilflächenspezifische Applikationen von Pflanzenschutzmitteln haben im Vergleich zu flächeneinheitlichen ein hohes Potenzial, die reduzierte Ausbringung von Pflanzenschutzmitteln zu fördern. Im Rahmen des Forschungsprojektes „AssSys“ wurden erstmals teilflächenspezifische Pflanzenschutzmaßnahmen mit Direkteinspeisung und einem automatisierten Applikations-Assistenzsystem für Herbizid- und Fungizidmaßnahmen ökonomisch bewertet. Die ökonomische Bewertung basiert auf Feldversuchen und einer Szenarioanalyse. Die Feldversuche wurden in den Jahren 2018 und 2019 in Norddeutschland durchgeführt. Als wichtigste Kennzahl auf Betriebsebene wurde die direkt- und arbeitserledigungskostenfreie Leistung (DAL) herangezogen. In der Szenarioanalyse wurden zwei teilflächenspezifische Anwendungsszenarien mit einer flächeneinheitlichen Behandlung verglichen, bezogen auf einen Modellbetrieb. Die Unkrautbonituren wurden als (1) Standardverfahren gemäß dem integrierten Pflanzenschutz, (2) kamerabasiert und (3) drohnenbasiert in den Feldversuchen durchgeführt. Das Assistenzsystem zielt darauf ab, Landwirte bei der Entscheidungsfindung und praktischen Umsetzung von teilflächenspezifischen Pflanzenschutzapplikationen in der Planungsphase oder einer Ex-post-Bewertung zu unterstützen. Für die automatisierte betriebswirtschaftliche Bewertung von teilflächenspezifischen Pflanzenschutzmittelapplikationen wurden mehrere Kennzahlen identifiziert und innerhalb eines Pflanzenschutzkosten- und Benchmark-Webservices im Assistenzsystem implementiert. Die Applikationskosten enthalten neben den Pflanzenschutzmitteln auch die Lohn- und Maschinenkosten für Bonituren und die Ausbringung. Investitionskosten für die notwendige technische Ausstattung zur teilflächenspezifischen Applikation wurden berücksichtigt. Die ökonomische Szenarioanalyse ergab durchschnittliche Kosteneinsparungen bei Pflanzenschutzmitteln, Lohn- und Maschinenkosten von 26 % bis 66 % für teilflächenspezifischen Applikationen im Vergleich zur flächeneinheitlichen. Die durchschnittliche DAL für teilflächenspezifische Applikationen von 787 € ha–1 im Vergleich zu 631 € ha–1 bei flächeneinheitlichen zeigt einen klaren betriebswirtschaftlichen Vorteil der teilflächenspezifischen Szenarien. Die teilflächenspezifische Applikation von Pflanzenschutzmitteln kann Landwirte bei der Umsetzung eines präzisen, nachhaltigen und wirtschaftlichen Pflanzenschutz-Managements unterstützen und dazu beitragen, die Ziele des neuen europäischen Green Deals zur Reduzierung der Pflanzenschutzmittelanwendungen und deren Risiken zu erreichen.Site-specific pesticide applications have a high potential to promote reductions in pesticides compared to conventional pesticide applications. Within the research project ‘AssSys’, site-specific pesticide applications with a direct injection sprayer system and an automatic application assistant were evaluated economically with respect to herbicide and fungicide applications. The economic assessment was based on field trials and scenario analysis. The field trials were conducted in 2018 and 2019 in the North of Germany. As key performance indicator at farm level, extended gross margins were calculated. In the scenario analysis, two site-specific application scenarios were compared to conventional uniform treatment, referring to a model farm. Weed monitoring was conducted as (1) standard procedure according to integrated pest management, (2) camera-based and (3) drone-based in the field trials. The application assistant aims to support farmers in decision-making and practical implementation of site-specific pesticide applications either in the planning stage or as ex-post assessment. For the economic assessment of site-specific pesticide applications, several key performance indicators were identified and implemented in the plant protection cost-webservice and benchmark-webservice within the application assistant. Pesticide application costs include plant protection products as well as labour and machine costs of monitoring and pesticide applications. Investment costs of the necessary technical equipment for site-specific applications were considered. The economic scenario-analysis showed average pesticide cost savings (plant protection products, labour and machine costs) from 26 % to 66 % for site-specific applications compared to conventional applications. The average extended gross margin for site-specific applications of 787 € ha–1 compared to 631 € ha–1 for conventional (uniform) application indicates a clear economic advantage of the site-specific application scenarios. Site-specific pesticide applications can support farmers in implementing precise, sustainable and also economic pesticide management and may thus contribute to meet the goals of the new European Green Deal to reduce pesticide use and risks of pesticides
Rootstock affects stress relieving enzymatic activity during bud break in \u27Red Globe\u27 grapevine under semi-arid condition
Get PDF The role of stress relieving enzymes during bud sprouting in grapevines has already been established in different varieties. However, data on \u27Red Globe\u27 variety under tropical conditions are not reported. The present study was conducted to generate data on stress relieving enzymatic activities during bud sprout in \u27Red Globe\u27 on different rootstocks under arid conditions of India. Influence of different rootstocks on stress relieving enzymes (catalase, peroxidase, ascorbic acid oxidase and polyphenol oxidase) involved in bud sprouting under tropical conditions with double pruning and single cropping pattern was evidenced. Positive interactions were observed between enzymatic activities of stress relieving enzymes, increased bud break (64.25 %) and reduction in days taken to bud sprout (8.43 days). Among the rootstocks under study, vines on 110R and own rooted vines have strong impact on stress relieving enzymes that resulted into early and increased bud sprouting. Also, the dynamics of enzymatic activity can be used as biological indicators for forecasting the end of bud dormancy and recommencement of growth
Anatomical physiological and biochemical processes involved in grapevine rootstock drought tolerance
Get PDFIn order to explore the drought resistance mechanism of grape rootstocks, two grape rootstock species, \u271103P\u27 (a drought-tolerant rootstock) and \u27101-14M\u27 (drought-sensitive), were treated with moderate water deficit (field capacity of 45-50 %). Throughout the experimental period, the leaves of \u271103P\u27 showed a higher stomatal conductance (gs), relative water content and photosynthetic rate (Pn) than \u27101-14M\u27, indicating \u271103P\u27 was more resistant to tolerant than \u27101-14M\u27. We propose that \u271103P\u27 could prevent water loss from leaves under drought conditions based on the discoveries that \u271103P\u27 had higher leaf phytohormone abscisic acid (ABA) content and leaf cuticular wax content, and smaller stomata aperture than those of \u27101-14M\u27. Additionally, the activities of H2O2-scavenging enzymes in leaves of \u271103P\u27 were higher than those of \u27101-14M\u27 under drought conditions, indicating the lipid peroxidation induced by H2O2 of \u271103P\u27 was less serious than that of \u27101-14M\u27. Therefore, better water-saving and higher reactive oxygen species (ROS) scavenging abilities contributed together to stronger drought resistance of \u271103P\u27 than \u27101-14M\u27
Effect of terroir on the glucosinolate content of Moringa oleifera grown in three agro-ecological zones of Ghana
Get PDFEnvironmental factors and cultural practices significantly influence the secondary metabolites in plants, e.g., glucosinolates, depending on the cultivar of each species. The present study analyzed the influence of specific environmental factors (e.g., temperature, rainfall, and relative humidity), elevation, and fertilization (i.e., nitrogen and sulfur) on the glucosinolate content in leaves of wild-grown Moringa oleifera from three agro-ecological zones in Ghana and selected M.oleifera accessions cultivated under semi-controlled field conditions.
The results showed that climate did not significantly influence total glucosinolate content in leaves of both wild-grown and cultivated accessions of M.oleifera, while elevation significantly influenced the total glucosinolate content of wild-grown plants. Fertilization had no significant impact on the total glucosinolate content of the cultivated accessions. Furthermore, wild-collected M.oleifera leaves from the three agro-ecological zones did not reveal a significant difference in their total glucosinolate content. For the cultivated accessions of M.oleifera, the agro-ecological zone, harvest time, and accession and the interactions among these factors significantly influenced the total glucosinolate content.
The results suggest that selecting suitable accessions, choosing suitable locations, and applying appropriate cultivation practices could contribute to optimizing the production of health-promoting Moringa plants with special emphasis on glucosinolate content
Deposition of an active substance on upper and lower leaf surface and implications on the efficacy in different ornamental plants depending on nozzle type and addition of a wetting-agent
Get PDFDie Verteilung eines Pflanzenschutzmittels im Pflanzenbestand ist ganz wesentlich von der Verfügbarkeit und Verwendung einer geeigneten Applikationstechnik abhängig. Nur eine gute Verteilung gewährleistet den sicheren Kontakt der Zielorganismen mit dem Wirkstoff. Das gilt insbesondere für Schädlinge die sich auf der Blattunterseite aufhalten. Die Auswirkung des Düsentyps sowie die Verwendung eines Netzmittels auf die Wirkstoffanlagerung an die Blattober- und -unterseite und die resultierende Wirksamkeit sind Gegenstand dieser Untersuchungen.Für die Ermittlung der Wirkstoffanlagerung wurde ein künstliches Blatt eingesetzt, bei dem die daran befestigten Glasfaserfilter als Blattober- bzw. -unterseite getrennt analysiert werden konnten. Die Verwendung einer Hohlkegeldüse erhöhte im Vergleich zu einer Flachstrahldüse die Anlagerung auf der Oberseite der künstlichen Blätter in schmalblättrigen Brachyscome multifida. Die Doppelflachstrahldüse unterschied sich nicht von den anderen Düsentypen. In breitblättrigen Pelargonium-Zonale-Hybriden und Fuchsia-Hybriden wurden keine Unterschiede zwischen den Düsentypen festgestellt. Die Wirkstoffanlagerung auf der Blattunterseite der künstlichen Blätter an der Fuchsia-Hybride und die Wirksamkeit auf Trialeurodes vaporariorum war unabhängig vom Düsentyp gering.The distribution of a plant protection product in the plant stand depends to a large extent on the availability and use of a suitable application technique. Only a good distribution guarantees the safe contact of the target organisms with the active ingredient. This applies in particular to pests which are on the underside of the leaves. The effect of the nozzle type as well as the use of a wetting agent on the active ingredient attachment to the upper and lower leaf surface and the resulting effectiveness are the subject of these investigations.For the determination of the active ingredient attachment an artificial leaf was used, in which the glass fiber filters attached to it could be analyzed separately as the upper and lower side of the leaf. The use of a hollow cone nozzle, as compared to the flat spray nozzle, increased the attachment on the upper side of the artificial leaves in narrow-leaved Brachyscome multifida. The double flat fan nozzle did not differ significantly to the other nozzle types. In broad-leaved Pelargonium-zonale-hybrids and Fuchsia hybrids no differences were found between nozzle types. The active ingredient attachment on the underside of the artificial leaves on the Fuchsia hybrid and the efficacy on Trialeurodes vaporariorum was low regardless of the nozzle type
High-resolution 3D phenotyping of the grapevine root system using X-ray Computed Tomography
Get PDFPlant roots are essential for water and nutrient uptake and contribute to the plants\u27 response to environmental stress factors. As the hidden half of a plant, investigation of root systems is highly challenging, most of available methods are destructive and very labour-intensive. In this proof-of-concept study, a non-invasive X-ray micro computed tomography (X-ray µCT) method was applied to investigate the phenotypic variation of the complex three-dimensional (3D) architecture of grapevine roots as a function of genotype and soil. Woody cuttings of \u27Calardis Musqué\u27, \u27Villard Blanc\u27 and V3125 (\u27Schiava Grossa\u27 x \u27Riesling\u27) were cultivated in polypropylene columns filled with two different soil types, clay loam and sandy loam, for 6 weeks. Afterwards, the columns were scanned once using the technique of X-ray µCT. The received raw data were analysed for the reconstruction of 3D root system models (3D model), which display a non-destructive visualization of whole, intact root systems with a spatial resolution of 42 µm. The 3D models of all investigated plants (in total 18) were applied to quantify root system characteristics precisely by measuring adventitious root length, lateral root length, total root length, root system surface area, root system volume and root growth angles from the woody cutting relative to a horizontal axis. The results showed that: (i) early root formation and root growth differed between genotypes, especially between \u27Calardis Musqué\u27 and \u27Villard Blanc\u27; and (ii) the soil type does influence adventitious root formation of V3125, but had minor effects on \u27Calardis Musqué\u27 and \u27Villard Blanc\u27. In conclusion, this innovative, high-resolution method of X-ray µCT is suitable for high resolution phenotyping of root formation, architecture, and rooting characteristics of grapevine woody cuttings in a non-destructive manner, e.g. to investigate root response to drought stress and would provide new insights into phylloxera root infection
Biological performance of the predatory mite Neoseiulus barkeri Hughes (Phytoseiidae): a candidate for controlling of three mite species infesting grape trees
Get PDFThe life history and predation rate of Neoseiulus barkeri (Phytoseiidae) feeding on Colomerus vitis (Eriophyidae), Tetranychus urticae (Tetranychidae) and Brevipalpus lewisi (Tenuipalpidae) were determined in the laboratory at constant temperatures of 25, 30 and 35 °C, relative humidity of 50 ± 5 % and a photoperiod of 16:8 h (light:dark). Within the temperature range studied, the increase of temperature from 25-35 °C led to a shortened development period and an increased total predation rate and reproduction. Survival during immature stages development surpassed 94 % at all the temperatures from 25 to 35 °C. The highest fecundity (59.50, 48.25 and 35.30 eggs per female) was recorded at 35 °C, while the minimum (40.25, 31.00 and 20.50 eggs per female) was at 25 °C when N. barkeri fed on C. vitis, T. urticae and B. lewisi, respectively. It is demonstrated in the life table parameters that when the predatory mite N. barkeri is fed on C. vitis, the highest reproduction rates (rm = 0.195, 0.210 and 0.232 females/female/day) are obtained, while feeding on B. lewisi gave the minimum of reproduction rates (rm = 0.095, 0.105 and 0.115) at 25 °C, 30 °C and 35 °C, respectively. The population of N. barkeri multiplied 20.45, 22.63 and 24.89 times in a generation time of 16.80, 14.75 and 12.50 days when fed on C. vitis at the same temperatures mentioned above, respectively, while N. barkeri multiplied 10.70, 12.88 and 14.36 times in a generation time of 23.20, 21.11 and 18.08 days when fed on B. lewisi at the same temperatures, respectively. This shows that N. barkeri is a promising control agent for C. vitis, T. urticae and B. lewisi on grape trees
The Influence of fermentation-like incubation on cacao seed testa and composition of testa associated mucilage
Get PDFBecause the testa of Theobroma cacao L. is a physical barrier for mass transfer of water and nutrients during germination, as well as in the fermentation process, analysis of the testa is necessary to understand these processes. This research deals with the morphological structure of the testa and its influence during fermentation of cacao seeds on the production of the aroma precursors of chocolate. Investigations have been carried out using fermentation-like incubations. For the first 48 hours of fermentation-like incubations, the seed represents a closed system with no transport of matter between the incubation-medium outside and the cotyledons inside. At this stage, the testa influences the course of the incubations by its barrier function. Much of this activity involves testa-associated mucilage. The composition of testa-associated mucilage is described
Photosynthesis, biochemical activity, and leaf anatomy of tree tomato (Solanum betaceum Cav.) plants under potassium deficiency
Get PDFThe effects of potassium (K) deficiency on the physiological, bio-chemical, and anatomical parameters of leaves in the tree tomato plants (Solanum betaceum Cav.) were evaluated during vegetative growth. The experiment was carried out for 135 days after treatment applications under greenhouse conditions, employing the nutrient solutions with the following treatments: control plants (without K de-ficiency) and the plants with K deficiency. The light response curve, photosynthesis at light saturation (Amax), light compensation point (Ic), transpiration rate (E), stomatal resistance (SR), and pigment contents in leaves were evaluated. Additionally, the maximum photochemical efficiency of PSII (Fv/Fm), contents of malondialdehyde (MDA), total soluble sugars, proline, and leaf anatomy parameters were assessed.
In the K-deficient plants, the reduction in Amax (66%), Ic (63.7%), E (66%), Fv/Fm (17.3%), contents of total chlorophyll (77.4%) and chlorophyll a (52%), thickness of leaf blade L (28.5%), palisade parenchyma PP (6.5%), and spongy parenchyma SP (9.5%) were observed, compared to the control plants. In contrast, the variables that increased significantly were SR (65%), MDA (52%), Upper epidermis thickness (Ue) (27.1%), and Lower epidermis thickness (Le) (22.3%). The potassium deficiency caused alterations in the plant development due to the influence on physiological, biochemical, and anatomical parameters, which suggests the importance of mineral nutrition with K for this plant