Development of compatible lignocellulolytic fungal consortium for rapid composting of rice straw

An experiment was conducted to evaluate the potential of lignocellulolytic fungi for rapid composting of rice straw. Forty-nine isolates of fungi were isolated from several natural and induced rice straw composting sources. Ten isolates were tested for their potential to decompose lignocellulosic rice straw by assessing their growth rate and biomass production, as well as their ability to decompose lignin and cellulose on rice-straw-powder-amended media. Four isolates (F26, F28, F29, and F44) were selected as potential lignocellulolytic agents for in-vitro compatibility study based on their optimum growth rate, biomass production, and lignocellulolytic activities. Six different interactions were found among four interacting isolates in the form of mutual intermingling, partial mutual intermingling, and inhibition at the contact point. Finally, a consortium of Aspergillus niger (F44) and Trichoderma viride (F26) was tested for in-vitro biodegradation of rice straw. The fungal consortium was able to decompose cellulose, hemicelluloses, lignin, and total carbon significantly (p � 0.05) over the control. The C/N ratio was reduced to 19.5 from an initial value of 29.3 in three weeks of the biodegradation process, thus showing the potential of this method for use in large-scale composting of rice straw

Analysis of simple sequence repeat markers linked with blast disease resistance genes in a segregating population of rice (Oryza sativa).

Among 120 simple sequence repeat (SSR) markers, 23 polymorphic markers were used to identify the segregation ratio in 320 individuals of an F(2) rice population derived from Pongsu Seribu 2, a resistant variety, and Mahsuri, a susceptible rice cultivar. For phenotypic study, the most virulent blast (Magnaporthe oryzae) pathotype, P7.2, was used in screening of F(2) population in order to understand the inheritance of blast resistance as well as linkage with SSR markers. Only 11 markers showed a good fit to the expected segregation ratio (1:2:1) for the single gene model (d.f. = 1.0, P < 0.05) in chi-square (χ(2)) analyses. In the phenotypic data analysis, the F(2) population segregated in a 3:1 (R:S) ratio for resistant and susceptible plants, respectively. Therefore, resistance to blast pathotype P7.2 in Pongsu Seribu 2 is most likely controlled by a single nuclear gene. The plants from F(2) lines that showed resistance to blast pathotype P7.2 were linked to six alleles of SSR markers, RM168 (116 bp), RM8225 (221 bp), RM1233 (175 bp), RM6836 (240 bp), RM5961 (129 bp), and RM413 (79 bp). These diagnostic markers could be used in marker assisted selection programs to develop a durable blast resistant variety

Early detection of basal stem rot disease (Ganoderma) in oil palms based on hyperspectral reflectance data using pattern recognition algorithms

Basal stem rot (BSR) is a fatal fungal (Ganoderma) disease of oil palm plantations and has a significant impact on the production of palm oil in Malaysia. Because there is no effective treatment to control this disease, early detection of BSR is vital for sustainable disease management. The limitations of visual detection have led to an interest in the development of spectroscopically based detection techniques for rapid diagnosis of this disease. The aim of this work was to develop a procedure for early and accurate detection and differentiation of Ganoderma disease with different severities, based on spectral analysis and statistical models. Reflectance spectroscopy analysis ranging from the visible to near infrared region (325–1075 nm) was applied to analyse oil palm leaf samples of 47 healthy (G0), 55 slightly damaged (G1), 48 moderately damaged (G2), and 40 heavily damaged (G3) trees in order to detect and quantify Ganoderma disease at different levels of severity. Reflectance spectra were pre-processed, and principal component analysis (PCA) was performed on different pre-processed datasets including the raw dataset, first derivative, and second derivative datasets. The classification models: linear and quadratic discrimination analysis, k-nearest neighbour (kNN), and Naïve–Bayes were applied to PC scores for classifying four levels of stress in BSR-infected oil palm trees. The analysis showed that the kNN-based model predicted the disease with a high average overall classification accuracy of 97% with the second derivative dataset. Results confirmed the usefulness and efficiency of the spectrally based classification approach in rapid screening of BSR in oil palm

Klimafolgenabschätzungen in der Wasserwirtschaft und deren Nutzen für die Praxis

KlimafolgenClimate ImpactsDer globale Klimawandel kann regional unterschiedliche Auswirkungen haben. Während sich die wissenschaftliche Forschung vor allem mit der Analyse der Daten beschäftigt, ist die fachliche Praxis darum bemüht, die Ergebnisse zu interpretieren und Handlungsempfehlungen daraus abzuleiten. Im Zuge des Projektes KliBiW (Globaler Klimawandel – Wasserwirtschaftliche Folgenabschätzung für das Binnenland) wurden die Auswirkungen des Klimawandels auf die Hochwasser- und Niedrigwasserverhältnisse in Niedersachsen untersucht. Hierzu wurden die Daten von zwei regionalen Klimamodellen (WETTREG2006 und REMO), beide angetrieben durch das Globalmodell ECHAM5/MPI-OM, räumlich interpoliert und die Niederschläge zum Teil zeitlich disaggregiert, um hoch aufgelöste Klimainformationen bereitzuhalten. Anschließend erfolgte die Kopplung mit einem hydrologischen Modellsystem (PANTA RHEI), das bereits in der Hochwasservorhersagezentrale des NLWKN im Einsatz ist. Über Langzeitsimulationen wurden zukünftige Veränderungen in den Abflussverhältnissen räumlich und zeitlich differenziert für das Aller-Leine Gebiet identifiziert. Als Betrachtungszeiträume dienten eine nahe Zukunftsphase (2021 – 2050) und eine ferne Zukunftsphase (2071 – 2100). Die Veränderungen verschiedener hydrologischer Hoch- und Niedrigwasser-Kenngrößen wurden gegenüber einem Kontrollzeitraum (1971 – 2000) aufgezeigt. Die Auswertungen an 8 Pegeln in Einzugsgebieten >1.000 km² auf Tageswertbasis und an 6 Pegeln in Einzugsgebieten <1.000 km² auf Stundenwertbasis zeigten, dass sich die Hochwassersituation zukünftig verschärfen kann. Während kleinere Hochwässer häufiger auftreten können, nehmen die Scheitelabflüsse insbesondere in der fernen Zukunft zu. Aussagen zu größeren Ereignissen sind aufgrund der großen Bandbreite der Ergebnisse jedoch mit erheblichen Unsicherheiten behaftet. Die Niedrigwasserverhältnisse zeigten eine Abnahme der Abflüsse, speziell im Sommer, sowie eine Zunahme der Dauer undnder Volumendefizite bei Trockenperioden. Hierbei erschien die Variabilität und Ausprägung der Trockenheit in kleineren Einzugsgebieten etwas größer. Die Nutzung dieser Erkenntnisse stellt die fachliche Praxis vor die Herausforderung, die Ergebnisse zu interpretieren und zu kommunizieren. Unsicherheiten in den Modellketten müssen berücksichtigt und, wenn möglich, quantifiziert werden. Die abgeleiteten hydrologischen Konsequenzen des Klimawandels können z.B. Anwendung finden in der gesetzlich geforderten Berücksichtigung der Auswirkungen des Klimawandels auf die Risikogebiete entsprechend der Hochwasserrisikomanagement-Richtlinie (2007/60/EG). Dieser Beitrag gibt einen Überblick über wasserwirtschaftlich relevante Auswertungen von Klimamodelldaten auf unterschiedlichen räumlichen Skalen und zeigt anhand ausgewählter Beispiele auf, wie primär im wissenschaftlichen Kontext erhobene Ergebnisse effektiv für praxisrelevante Fragestellungen genutzt werden können

Hochwasser und Sturzfluten an Flüssen in Deutschland

Flusshochwasser werden in lokale und plotzliche Sturzfluten und in Hochwasser an groseren Flussen unterschieden. Fur verschiedene Hochwasserindikatoren und Flusseinzugsgebiete ergeben sich erhebliche Unterschiede, wobei sowohl uberwiegend aus Regen als auch uberwiegend aus Schmelzwasser gespeiste Hochwasserereignisse betrachtet werden. Besondere Aufmerksamkeit finden Hochwasserereignisse an Rhein, Elbe, Weser und Ems sowie die Entwicklung von Sturzfluten infolge von Extremniederschlagen kurzer Dauer, wobei die Beobachtungen und Trends zu Modellierungsergebnissen in Beziehung gesetzt werden. Auch die Notwendigkeit von Anpassungsmasnahmen aufgrund uberwiegend positiver Trends wird diskutiert

Dissolved organic matter (DOM) in the estuaries of Ob and Yenisei and the adjacent Kara Sea, Russia

Based on observations during four scientific expeditions to the Kara Sea and the Siberian rivers Ob and Yenisei we determined the discharge, distribution and characteristics of dissolved organic matter (DOM). Surface concentrations of dissolved organic carbon (DOC) ranged from 151 IlM C in the northern Kara Sea to 939 IlM C in the river Ob. The estimated annual mean DOC concentration in the Yenisei (681 IlM C) was slightly higher than in the Ob (640 IlM C). Dissolved organic nitrogen (DON) concentrations typically varied between 5 and 15 IlM N with higher values in the rivers. Freshwater discharge and DOC concentrations experienced pronounced seasonal variations strongly affecting the spatial and temporal distribution of DOM in the Kara Sea. The largely conservative distribution of DOC and DON along the salinity gradient indicated the predominantly refractory character of riverine DOM. This observation was consistent with laboratory experiments, which showed only minor losses due to flocculation processes and bacterial consumption. Optical properties and relatively high C/N ratios (19 to 51) of DO M suggest that a large fraction of river DOM is of terrestrial origin and that phytoplankton contributed little to DOM on the Kara Sea shelf during the sampling periods. Together, the rivers Ob and Yenisei discharge about 8 Tg DOC yr- I into the Kara Sea. Due to the absence of efficient removal mechanisms in these estuaries the majority of riverine DOM appears to pass the estuarine mixing zone and is transported towards the Arctic Ocean

La série saumâtre et continentale d'âge Miocène moyen et supérieur d'Eivissa (ex-Ibiza, Baléares)

At first, it is recalled that the main tectonics of Eivissa (Ibiza) involves white marls of upper Burdigalian- lower Langhian, with abundant planktonic microorganisms. But, near the south-west promontory of the island, in a site discovered a century ago by Vidai and Molina (1888), one find directly transgressive on the Senonian, polygenic conglomerates, then a sandy marly formation with Bivalvia (Cmssos- crea gryphoides, Mytilus aquitanicus, ...) and few benthic Foraminifera, finally coaly clays with brackish or estuary Gastropods. This "Formation of Cap Jueu" has also provided Langhian-like scarce paiynological assemblages. Strata of the same sedimentary cycle, also involved in the tangential tectonics, may be pointed out at the top of the imbrication of Roques Altes (ex- Rocas Altas), South West of la Talaia of Sant Josep (ex- San José) and near ant Rafael, maybe dating from the Tortonian (?) by microflora. It is possible to group here the "top conglomerates" from the center of the island, which lie up to Tnas, but usually ravining lower Langhian marls. So, an independent sedimentary cycle, prior to paroxysmal tectonics, dated as "middle" - ? upper Miocene (Langhian to ? Tortonian), may be defined, which goes before the deposit of marine "upper" Tortonian (Limestones of Portinatx), posterior to the main compressive phase. Clayey interstratifications in these limestones have provided poor paiynological assemblages corresponding to this Tortonian age. In short, the Miocene from Eivissa shows three independent sedimentary cycles which enable to date tectonic episodes concerning this eastern extension of Betic Cordilleras