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The application of diniconazole and prohydrojasmon as plant growth regulators to induce growth and tuberization of potato
Get PDFThe potato is a major vegetable crop around the world, and tuberous hypertrophy is a highly complex developmental process effected by various factors that play central role in potato growth. Tuber growth under hypertrophic conditions is regulated by variations in carbohydrates and endogenous phytohormones. In the present study, we aimed to establish the basis for the enlargement of potato tubers, including changes in the chemical content of factors related to tuber formation and hypertrophy based on phytohormonal regulation, plants height and tuber biomass and other selected attributes. Our results reveal that the application of plant growth regulators such as diniconazole (Din) and prohydrojasmon (PDJ) significantly impact on potato plants growth and yield, including that of tubers. Plants treated with Din and PDJ effectively showed stunted growth and re-duced development but enhance the tuber formation and its weight. Plants treated with Din and PDJ significantly reduced the GAs and ABA accumulation and increase the sucrose level and cause significant increase in tuber development. In conclusion, a higher gibberellin content in potatoes may inhibit tuberization. Diniconazole and PDJ treatment reduced gibberellin accumulation, which in turn regu-lated abscisic acid content, demonstrating that the abscisic acid content mostly increased as gibberellin content decreased, and thereby promoting tuberization
Soil transmission studies with four pome fruit viruses
Get PDFIn Topf- und Feldversuchen wurde die Bodenübertragung der Kernobstviren Chlorotisches Blattfleckenvirus des Apfels (ACLSV), Apfelmosaikvirus (ApMV), Stammfurchungsvirus des Apfels (ASGV) und Stammnarbungsvirus des Apfels (ASPV) untersucht. Nicht-inokulierte Bäume von Apfelsämlingen wurden zwischen inokulierte Bäume, die entweder mit ACLSV/ApMV oder ASGV/ASPV doppelt infiziert waren, gepflanzt und mit der Reversen Transkriptase-PCR (RT-PCR) wiederholt auf Infektionen getestet. Im ersten Topfversuch konnte ein hohes Ausbreitungspotenzial der Viren festgestellt werden. 46 % der nicht-inokulierten Bäume waren nach vier Jahren mit einem oder beiden der Viren infiziert. In einem zweiten Topfversuch, in welchem der Wurzelkontakt zwischen inokulierten und nicht-inokulierten Bäumen durch ein feinmaschiges Netz eingeschränkt war, wurde dagegen nur eine einzige Virusübertragung nachgewiesen. In einem dritten Topfversuch, in welchem nicht-inokulierte Bäume mit einem Bodeneluat bewässert wurden, welches aus dem ersten Topfversuch stammte, konnte keine Virusübertragung festgestellt werden. Darüber hinaus ließen sich in Eluaten aus dem ersten und zweiten Topfversuch keine Virionen nachweisen. Im Feldversuch mit zwei parallelen Reihen von Sämlingen, von denen nur eine Reihe mit virus-inokulierten Bäumen durchsetzt war, waren nach 46 Monaten fünf von 44 (11 %) der nicht-inokulierten Bäume in der durchsetzten Reihe mit einem oder zwei Viren infiziert. In der anderen Reihe, die ein Jahr später gepflanzt wurde, wurde nur eine einzige Infektion gefunden. Sowohl im Feld- als auch im ersten Topfversuch wurden erste Virusübertragungen nach 17,5 Monaten Expositionszeit festgestellt, die meisten fanden jedoch zwischen dem dritten und vierten Jahr statt. ACLSV wurde etwa doppelt so oft wie ApMV übertragen, die Übertragungsraten für ASGV und ASPV waren dagegen gleich. Einzel- und Doppelübertragungen traten im Feldversuch gleich häufig auf, im ersten Topfversuch waren Einzelinfektionen jedoch nahezu zweimal so häufig wie Doppelinfektionen. Für eine Beteiligung pflanzenparasitärer Nematoden an den Virusübertragungen fanden sich keine Hinweise. Die Ergebnisse dieser Studie legen den Schluss nahe, dass die Übertragung aller vier Viren auf Wurzelverwachsungen zurückgeführt werden kann.Soil transmission of the pome fruit viruses Apple chlorotic leafspot virus (ACLSV), Apple mosaic virus (ApMV), Apple stem grooving virus (ASGV) and Apple stem pitting virus (ASPV) was studied in pot and field trials. Non-inoculated recipient trees of apple seedlings were placed between inoculated donor trees, which were double-infected with either ACLSV/ApMV or ASGV/ASPV, and tested repeatedly by reverse transcription PCR (RT-PCR) for infections. In the first pot trial, a high potential for virus spread was demonstrated. 46% of the recipient trees were infected either by one or two of the viruses after four years. In a second pot trial, where the root contact between donor and recipient trees was restricted by a fine-meshed net, only a single virus transmission was detected. In a third pot trial, non-inoculated trees were watered with a soil eluate generated in the first pot trial, but no virus transmission was recorded. Moreover, no virions could be detected in the eluates generated from the first and second pot trial. The field trial consisted of two parallel rows of apple seedlings, where only one row was interspersed with virus-inoculated trees. In this row a total of five non-inoculated plants out of 44 (11%) tested positive for one or both viruses after 46 months. In the other row, which was planted one year later, only a single infection was found. The earliest virus transmissions in the field- and in the first pot trial were recorded after 17.5 months of exposure, however, most infections occurred between the third and fourth year. ACLSV was transmitted about twice as often as ApMV, whereas the rate for ASGV and ASPV was the same. The number of single and double virus transmissions was equal in the field, but in the first pot experiment single infections were recorded almost twice as often as double infections. There was no evidence that plant-parasitic nematodes were involved in virus transmission. The results of this study suggest that the transmission of all four viruses can be attributed to root grafting
Near-infrared spectroscopy in process control and quality management of fruits and wine
Get PDFRecently, rapid quality assessment of food is an increasingly important topic. The rising demand of consumers for high quality products generates a need to establish fast and suitable analytical methods. Near-infrared (NIR) spectroscopy has turned out to be a time-saving, cheap, easy-to-use and environmentally friendly technique, which can be applied for the determination of manifold quality attributes in various kinds of food matrices. This article gives overview of the basic principles of near-infrared measurements and describes the immense field of applications, with the main focus on fruits, grapes and wine and the evaluation of wine aroma
A comparative analysis of pawpaw (Asimina triloba) quality and nutritional data
Get PDFThe North American pawpaw (Asimina triloba [L.] Dunal) from sixteen varieties was analyzed for size, pH, oBrix, firmness, and pulp and skin color. A varietal composite was used to determine nutrient composition. Data from the current study was compared to previous literature values, and all results fit well with previous literature. The average weight of the fruits across all varieties was 194 g and ranged from 122 to 292 g, the pH of the fruits ranged from 5.4 to 6.3, the average oBrix ranged from 18.2% to 26.1%, and firmness ranged from 0.391 kg to 0.727 kg. The color of the skin and the pulp differed by variety but was well-within previously reported values. Pawpaw pulp nutritional values verified the nutritional values previously reported for pawpaw pulp from fruit harvested in Korea and will be used as the basis for inclusion of pawpaw in the USDA National Nutrient Database for Standard Reference. Several specific recommendations are made: 1) firmness of 0.2 to 0.7 kg of force can be used to describe ripe pawpaw fruit; 2) the serving size for raw pawpaw pulp is one-half cup (120 g); and 3) pawpaw pulp nutrition compares favorably to that of banana or mango
Sweetened nopal flakes: a functional snack
Get PDFNopal (Opuntia spp. and Nopalea spp. genera) is a crop, recognized for its nutritional and medicinal properties; however, there are some underused species, despite the great genetic diversity in Mexico. The genus Opuntia spp. is the most consumed nopal, whereas Nopalea spp. has low commercial demand, possibly because their nutraceutical attributes are unknown. Additionally, the nopal pads or cladodes are little accepted by many consumers, due to their texture and flavor.
The study objectives were 1) evaluate the nutraceutical content and antioxidant activity of four nopal cultivars: Nopalea cochenillifera cv. Texas (NT) and Opuntia ficus-indica cv. Jade (OJ), Milpa Alta (OMA), and Atlixco (OA); 2) develop nopal flakes, sweetened with rebaudioside A, from the cultivar with the best nutraceutical quality and sensory acceptability. Ascorbic acid, total phenolics, and total flavonoids were determined by spectrophotometric methods, individual flavonoids (quercetin, kaempferol, and isorhamnetin) by HPLC, and antioxidant activity by the DPPH assay. OA was the cultivar with the best nutraceutical quality.
The sweetened nopal flakes of OA, at a concentration of 1.1 mg g-1 rebaudioside A, had the highest sensory acceptability by the panelists in intensity and sweetness preference. The addition of rebaudioside A improved the product’s flavor and contributed to preserve the flavonoids and antioxidant activity. These results will contribute to the chemotaxonomy of O. ficus-indica and N. cochellinifera species,and to the utilization of nopals as functional foods, due to their nutraceutical quality
Dually-beneficial habitats serve as a practical biodiversity mainstreaming tool in European crop production
Get PDFDie Schaffung semi-natürlicher Habitate in Europa ist eine Maßnahme, um dem Verlust von Habitaten entgegen zu wirken, die durch die Vereinfachung landwirtschaftlicher Landschaften entstanden sind. Die meisten wissenschaftlichen Arbeiten zu Habitaten fokussieren auf Artenschutz, während Untersuchungen zur Bereitstellung verschiedener Agrar-Ökosystem-Dienstleistungen begrenzt sind. Kenntnisse über den Nutzen derartiger Habitate für den Ackerbau, würden es jedoch ermöglichen, sie zur Standard-Maßnahme („mainstreaming“) für die Integration von Biodiversität im Ackerbau einzusetzen. Diese Arbeit zielt darauf ab, zweifach-nützliche Habitate zu identifizieren, die in Getreide, Raps und Sonnenblumenfeldern eingerichtet werden könnten, da diese die drei wichtigsten Ackerkulturen in Europa darstellen. Diese Kulturen werden oft in vereinfachten Agrarlandschaften angebaut, wo die Notwendigkeit zur verbesserten Konnektivität der biologischer Vielfalt auf Landschaftsebene hoch ist, und ihre Integration den größten Nutzen verspricht. Eine qualitative Beurteilung dieser Habitate erfolgt im Rahmen ökologisch fokussierter Agrar-Ökosystem-Dienstleistungen und -Undienste, erläutert Kompromisse (Vor- und Nachteile) für den Ackerbau sowie potentielle Synergien. Vier unterschiedlich geeignete Gruppen von Habitaten konnten identifiziert werden: 1. Brachfelder/Teilflächen, 2. Bewirtschaftete Felder/Teilflächen, 3. Bewirtschaftete Blühflächen, 4. Bewirtschaftete Ackerrandstreifen.Semi-natural habitat creation in Europe is a tool to address habitat loss, caused by agricultural landscape simplification. Research on habitats is mostly conservation-centered, while studies on their delivery of multiple agro-ecosystem services are limited. However, knowledge about these habitats’ suitability for production could make them a practical biodiversity mainstreaming tool. This paper identifies potential dually-beneficial (db) habitats for use in cereals, oilseed rape, and sunflowers, the three major EU arable field crops. They are often grown in simplified landscapes, where the need for improved biodiversity connectivity at landscape level is high and their integration expected to be most effective. The paper provides a qualitative survey of the db-habitats effects on agro-ecosystem services and disservices while addressing trade-offs and synergies thereby using an ecology-focused agro-ecosystem services and disservices framework. Four differently suitable db-habitat groups were identified: 1. Uncropped fields/subfield areas, 2. Managed fields/subfield areas, 3. Managed flower areas and 4. Managed margins
Lime application reduces potassium and nitrate leaching on sandy soils
Get PDFKalium (K)-Auslaugung kommt in leicht strukturierten Böden häufig vor und reduziert die im Boden für die Pflanzen verfügbare Menge K. Diese Studie untersuchte die Auswirkung der Kalkanwendung und der K-Raten (null, 20, 60 kg K/ha) auf die K-Auslaugung und andere Sickerwasserparameter von vier sandigen Böden im Westen Australiens. Drei von vier Böden unterschieden sich in der K-Auslaugung nicht zwischen den Raten von Null und 20 kg K/ha, während 60 kg K/ha die K-Auslaugung in allen vier Böden erhöhten. Bei den Merredin-Böden verzögerte die Kalkanwendung die K-Auslaugung bei 60 kg K/ha deutlich und zeigte einen K-Auslaugungspeak bei 4,75 Porenvolumen (PV) im gekalkten Boden (pHCaCl2: 6,20), jedoch bei 3 PV im nicht gekalkten Boden (pHCaCl2: 4,50), und das Kalken reduzierte auch die Gesamtmenge an ausgelaugtem K und NO3. In ähnlicher Weise trat der Peak der K-Auslaugung bei 2–3 PV in den anderen beiden nicht gekalkten Böden auf. Die maximalen NO3-Konzentrationen von Sickerwasser bei 60 kg K/ha betrugen 46 mg/l bei 2 PV mit Kalk gegenüber 110 mg/l bei 1,25 PV ohne Kalk, während die Menge an ausgelaugtem NO3 aus Böden ohne K-Zugabe größer war als aus den mit K behandelten Böden. Die Ergebnisse legen nahe, dass die Kalkung eines sauren Sandes die K- und NO3-Auswaschung verlangsamen und verringern kann und erhebliche Auswirkungen auf das K-Dünger-Management auf solchen Böden hat.Potassium (K) leaching is common in light-textured soils and reduces soil available K to plants. This study examined the effect of lime application and K rates (nil, 20, 60 kg K/ha) on K leaching and other leachate parameters of four sandy soils in Western Australia. Three out of four soils did not differ in K leaching between the rates of nil and 20 kg K/ha, whereas 60 kg K/ha increased K leaching in all four soils. For the Merredin soils, lime application markedly delayed K leaching at 60 kg K/ha, showing K leaching peak at 4.75 pore volume (PV) in the limed soil (pHCaCl2: 6.20) but at 3 PV in the non-limed soil (pHCaCl2: 4.50), and liming also reduced total amount of leached K and NO3. Similarly, the peak of K leaching occurred at 2–3 PV in the other two non-limed soils. Maximum leachate NO3 concentrations at 60 kg K/ha were 46 mg/L at 2 PV with lime versus 110 mg/L at 1.25 PV without lime, while the amount of leached NO3 from nil K soils was greater than from the K treated soils. The results suggest that liming of an acid sand can slow down and reduce K and NO3 leaching and have significant implication for K-fertilizer management on such soils