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Effects of elevated carbon dioxide and climate change on biomass and nutritive value of Kyasuwa (Cenchrus pedicellatus Trin.): Kyasuwa biomass and nutritive value under elevated CO2
No full textAtmospheric carbon dioxide enrichment enhances plant growth and development and may alter the nutritive value of grasses. The objective of this study was to evaluate growth, biomass partitioning and nutritive value of Kyasuwa under combinations of atmospheric CO2 concentrations, watering and fertilization treatments. Plants were grown in two greenhouse chambers; with ambient (aCO2; 400 ppm) and elevated CO2 (eCO2; 950 ppm), two watering and three fertilization regimes. Elevated CO2 reduced stomatal conductance by 40%, root to shoot ratio by 8%, leaf to stem ratio (L:S) by 3%, protein content by 14% and Acid Detergent Lignin (ADL) by 23% with no significant changes in total biomass and C/N ratio however, slight increases in leaf area (2%) and Acid Detergent Fiber (ADF) by 4%. Higher fertilization resulted in increased biomass parameters only in well-watered plants while; a lower C/N ratio was recorded with higher fertilization. The L:S ratio was decreased with fertilization while ADL was increased at higher fertilization in well-watered plants. Interactive effects were recorded for ADF content and shoot height. Future eCO2 will be unfavorable to Kyasuwa growth and biomass production making them less competitive with a reduced nutritive value in drought prone and infertile soils
Application of 1-methylcyclopropene in fruit of five apple cultivars grown in Serbia
Get PDFFruits of five apple cultivars were treated using 1-methylcyclopropene (1-MCP or SmartFreshTM) after cropping and were stored at normal atmosphere 2 ± 0.5 °C, 90 ± 5% relative humidity (RH) and 20.9 kPa O2 + <0.5 kPa CO2. Fruit firmness was assessed at three periods: 7 d after storing, 120 d after storing and 30 d after the second assessment and storing at room temperature. Contents of K in all of the cultivars and in all years of study varied within the average values between 1390.5 and 2028.0 mg kg-1, while the Ca content varied between 21.7 and 59.5 mg kg-1. The K:Ca ratio was the lowest in cultivar ‘Granny Smith’ (24.0) and the highest in ‘Redchief’ (99.1). Application of 1-MCP made the strongest impact on fruit firmness of the cultivars ‘Granny Smith’ and ‘Idared’ in all measuring periods. Cultivars ‘Redchief’, ‘Čadel’ and ‘Morrens Ionagored’ responded well to the application of 1-MCP in the storage conditions, whereas the effect of its application influenced conservability of the fruits stored at room temperature except in fruits of the cultivar ‘Morens Jonagored’. Application of 1-MCP made an important effect on the preservation of fruit firmness, all in accordance with the degree of ripeness of the fruits subjected to the treatment and the contents of K, Ca and K:Ca ratio. This study indicates that the use of 1-MCP treatment in post harvest handling of apples is promising for maintaining the freshness and quality of fruits
Effect of selenium application on mineral macro- and micronutrients and antioxidant status in strawberries
Get PDFThe application of selenium (Se) as sodium selenite (Na2SeO3) at 0, 2, and 4 mg L-1 concentrations in nutrient solution to strawberry plants was evaluated. Selenium did not modify the dry weights of the roots, stems, leaves, and fruits, or the fresh weights of the stems and fruits. The 4 mg L-1 concentration caused decreases in the fresh weights of the roots and leaves and in the yield. The mineral content of different plant organs changed but was not adversely affected by Se applications, with the 2 mg L-1 treatment having a lower impact on mineral concentration variation, as well as temporary positive effects on the fruits’ antioxidant status. The fruit pH was not adversely affected by application of Se. Se application in nutrient solution proved to be an adequate technique to increase the Se content in all plant organs. Se concentration exhibited a differential distribution, with the highest levels in the roots, followed by the leaves and crowns; the fruits had the lowest levels, reaching an average concentration of 31.2 mg kg-1 of dry weight. By contrast, fruits from the untreated plants obtained an average concentration of only 6.35 mg kg-1, with no decreases in the concentrations of other mineral elements in treated plants
Intensity and risk of chemical pesticides when cultivating sugar beet, silage maize and winter wheat in crop rotations
Get PDFDer Einsatz chemischer Pflanzenschutzmittel dient zum einen der Sicherstellung des Ertrages, steht jedoch auch aufgrund von möglichen ökologischen Risiken in der Kritik. Der Nationale Aktionsplan zur nachhaltigen Anwendung von Pflanzenschutzmitteln zielt auf die Reduzierung dieser Risiken ab. In der vorliegenden Studie wurden chemische Pflanzenschutzmaßnahmen in Feldversuchen in den Jahren 2011–2014 in den Fruchtfolgen Zuckerrüben-Winterweizen-Winterweizen, Silomais-Winterweizen-Winterweizen, Silomais-Zuckerrüben-Winterweizen und Silomais im Daueranbau an zwei Standorten untersucht. Als Indikator der Intensität diente der „Behandlungsindex“, das Umweltrisiko wurde mit dem Simulationsmodell „SYNOPS“ für Stellvertreterorganismen in den Nichtziel-Kompartimenten „Oberflächengewässer“, „Saumbiotope“ und „Boden“ kalkuliert. Der Behandlungsindex variierte zwischen den Fruchtfolgen von 5,1 bis 20,6 und das Umweltrisiko wurde überwiegend als sehr niedrig bis mittel kalkuliert. Es existierte keine Korrelation zwischen der Intensität und dem Umweltrisiko über die Fruchtfolgen. Silomais im Daueranbau hatte die geringste Intensität, jedoch war das Umweltrisiko höher. Für Silomais und Winterweizen existierten herbizide und fungizide Wirkstoffe, für die ein nicht tolerables Umweltrisiko kalkuliert wurde. Konsequenzen für den Integrierten Pflanzenschutz ergeben sich unter anderem aus der Wahl weniger toxischer Wirkstoffe, einer Reduktion der Gesamtaufwandmenge und nicht-chemischer Maßnahmen, wie mechanische Unkrautregulierung oder resistente Sorten.The use of chemical pesticides serves at reducing crop yield losses, but is also criticised because of possible ecological risks. The German national action plan on sustainable use of plant protection products aims at reducing these risks. The current study investigated pesticide applications on two sites in Germany in 2011–2014, comparing different crop rotations with sugar beet, silage maize and winter wheat as well as silage maize under continuous cultivation. The treatment index was used as an indicator for the pesticide application intensity. The environmental risk was calculated by the simulation model “SYNOPS” for reference organisms in the non-target compartments “surface water”, “field margin biotope” and “soil”. The treatment index varied between crop rotations from 5.1 to 20.6 and the environmental risk was mostly calculated as very low to medium. No correlation between intensity and environmental risk of crop rotations was found. The lowest treatment index was calculated for silage maize in continuous cultivation, but, the environmental risk was higher. Some herbicidal and fungicidal active ingredients used in silage maize and winter wheat were identified for which non tolerable environmental risks were calculated. Consequences for the Integrated Pest Management result from the choice of active substances with lower toxicity, a reduction of the entire application rate and non-chemical measures like mechanical weed control or resistant varieties
Enhanced expression of radish-specific proteins in a disomic rapeseed-radish chromosome addition line resistant to root-knot nematodes
Get PDFWurzelgallennematoden sind weltweit für ganz erhebliche Ertrags- und Qualitätseinbußen verantwortlich. Für den tropischen und subtropischen Teil Chinas sind insbesondere Meloidogyne incognita und M. javanica von Bedeutung. Die disome Additionslinie ee einer kompletten Serie von Raps-Rettich-Additionslinien hatte sich in vorherigen Versuchen als resistent gegenüber diesen beiden Nematodenarten erwiesen. Das Proteinmuster dieser disomen Additionslinie wurde mittels zweidimensionaler Gelelektrophorese und Image Master 5.0 Software mit dem des Rettich-Donors und dem des Raps-Rezipienten verglichen. Differentiell exprimierte Proteine wurden mittels MALDI-TOF-TOF/MS identifiziert. Drei Rettich-spezifische Proteine, die eine erhöhte Expression in der Additionslinie ee aufwiesen, sollen in einem zweiten Schritt auf eine potentielle Funktion im Resistenzmechanismus untersucht werden.Root-knot nematodes cause significant economic losses worldwide each year. Species with especially high relevance in the tropical and subtropical part of China are Meloidogyne incognita and M. javanica. The disomic rapeseed-radish chromosome addition line ee was shown in former experiments to be highly resistant against these southern root-knot nematodes. In this study, differentially expressed proteins in the roots of the addition line ee, its radish donor line and its rapeseed recipient line cv. Madora were screened by two-dimensional gel electrophoresis and Image Master 5.0 software. These proteins were identified by MALDI-TOF-TOF/MS. Three radish-specific proteins with an increased expression in rapeseed-radish addition line ee will be further analyzed for their potential role in nematode resistance
Parasitic fungi on leaves of Black Cherry: A contribution to biological plant protection
Get PDFEs werden vier auf der Spätblühenden Traubenkirsche (Prunus serotina) vorkommende Pilzarten beschrieben, einschließlich ihrer Krankheitsbilder und ihrer taxonomischen sowie infektionsbiologischen Besonderheiten. Asteroma padi gilt als Krankheitserreger und Verursacher hell brauner Flecke. Der Pilz besitzt eine endophytische Entwicklungsphase, die durch Fraßtätigkeit von Insektenlarven in eine pathogene Phase übergehen kann. Paecilomyces crassipes sp. nov. wird erstmals als neue Art beschrieben und abgebildet. Phoma pomorum besitzt ein ähnliches Krankheitsbild wie Asteroma padi, unterscheidet sich jedoch von dieser durch kleinere Sporen. Taphrina farlowii, die als „verschollene Art“ bekannt geworden ist, verursacht an jungen Blättern blasenartige, farblich auffällige Deformationen. – Es wird die Frage gestellt, ob einer der genannten Pilze als „Mykoherbizid“ zur Eindämmung von Prunus serotina eingesetzt werden kann.Four fungus species occurring on Wild Black Cherry (Prunus serotina) are described, including their symptoms and taxonomic and infection biology characteristics. Asteroma padi is considered to be the causative agent of light-brown leaf spots. The fungus has an endophytic stage of development, which can change into a pathogenic phase caused be feeding of insect larvae. Paecilomyces crassipes sp. nov. is described here for the first time as a new species. Phoma pomorum is causing symptoms similar to Asteroma padi, but differentiated by smaller spores.Taphrina farlowii, known as “lost species”, causes bubble-like, conspicuously coloured deformations on young leaves. – This article raises the question whether one of the mentioned fungi can be applied as “mycoherbicide” against the spreading of Prunus serotina
