Karakteristik Spora Tumbuhan Paku Asplenium Kawasan Hutan Raya R. Soerjo

Asplenium is one genus ferns aspleniaceae tribal members. Identification of the classification of the species can be determined by one of the morphological characteristics of the spores. Spore morphological characteristics include the shape, size, and type aperture ornamentation. The purpose of this study is to describe and analyze the species based on morphological characters spores. The method used is descriptive explorative to explore ferns Asplenium. The research found that five types of Asplenium is Asplenium nidus, Asplenium robustum, Asplenium salignum, Asplenium tenerum, and Asplenium unilaterale. The difference of 5 species Asplenium lies in the type of ornamentation characteristic morphology and size of the spores, whereas the equation is the shape, size and type categories aperture spores.Asplenium merupakan salah satu marga tumbuhan paku anggota suku Aspleniaceae. Identifikasi penggolongan spesies dapat ditentukan melalui salah satu karakteristik morfologi spora. Karakteristik morfologi spora meliputi bentuk, ukuran, apertura dan tipe ornamentasi. Tujuan penelitian ini adalah mendeskripsikan dan menganalisis karakter spesies berdasarkan morfologi spora. Metode penelitian yang digunakan ialah deskriptif eksploratif untuk mengeksplorasi tumbuhan paku Asplenium. Hasil penelitian ditemukan 5 jenis dari Asplenium yaitu Asplenium nidus, Asplenium robustum, Asplenium salignum, Asplenium tenerum, dan Asplenium unilaterale. Perbedaan dari 5 jenis spesies Asplenium terletak pada ciri morfologi tipe ornamentasi dan ukuran spora, sedangkan persamaan terletak pada bentuk, kategori ukuran dan tipe apertura spora

Complex systems and applied linguistics

This book introduces and develops the potential of complex systems as a metaphor or supra-theory for systems in applied linguistics. Change and heterogeneity are central to complex systems theory and to the resonances that we find between complex systems and applied linguistics systems. The book explores these resonances and what happens when complex systems theory is used to make sense of central areas of applied linguistic concerns: language, language learning, discourse and the language classroom. Principles of complex systems theory are explained, drawing on work that has been most developed in the biological sciences and that is being extended into the social sciences, developmental psychology and other applied disciplines. These principles importantly include descriptions of change over time (system dynamics) that work for all levels and scales: movement from temporary and relative stability through adaptive behaviours and self-organisation to the emergence of new patterns that are not amenable to reductive explanations. Seeing applied systems as complex, adaptive and dynamic opens up new conceptualisations of properties and activities, enables new questions about how people use, learn and teach languages, and demands new ways of investigating behaviour and development

Comparison of cultural growth and in planta quantification of Didymella pinodes, Phoma koolunga and Phoma medicaginis var. pinodella, causal agents of ascochyta blight on field pea (Pisum sativum)

The causal agents of ascochyta blight on field pea in South Australia, Didymella pinodes, Phoma medicaginis var. pinodella and Phoma koolunga, are isolated from a single plant within a crop, suggesting competition for space and nutrients. Interactions among these pathogens were investigated. Diameters of colonies of D. pinodes and of P. medicaginis var. pinodella were significantly reduced on PDA amended with filtrate from broth cultures of P. koolunga as were diameters of colonies of D. pinodes on PDA amended with filtrate from P. medicaginis var. pinodella or D. pinodes. This effect was negated when cultures were transferred to unamended PDA, indicating filtrates were fungistatic instead of fungicidal. The diameter of P. koolunga colonies was not influenced by filtrate from any of the three species. When pathogens were co-inoculated in pairs onto leaves on field pea plants, the quantity of DNA of D. pinodes and of P. medicaginis var. pinodella was significantly reduced if co-inoculated with P. koolunga. The quantity of DNA of P. koolunga was not influenced by co-inoculation. When co-inoculated onto excised leaf disks on sterile water the mean lesion diameter due to D. pinodes and to P. medicaginis var. pinodella was significantly reduced if co-inoculated with P. koolunga isolate DAR78535. Lesions caused by D. pinodes were significantly reduced when inoculum was self-paired. Conversely the diameter of lesions caused by P. koolunga DAR78535 increased when self-paired or when co-inoculated with P. medicaginis var. pinodella. Unlike leaf disks on sterile water, co-inoculation had no influence on lesion size or quantity of pathogen DNA in leaf disks on water agar. Antagonism, including self-antagonism, was detected among these species, leading to reduction in lesion size and quantity of pathogen DNA. The slower growing species, P. koolunga, was not self-antagonistic, and in a few instances the effect of co-inoculation was additive or synergistic.J.A. Davidson, M. Krysinska-Kaczmarek, Herdina, A. McKay, E.S. Scot

Persistence of DNA of Gaeumannomyces graminis var. tritici in soil as measured by a DNA-based assay

Herdina, Stephen Neate, Suha Jabaji-Hare and Kathy Ophel-Kelle

A new species of Phoma causes ascochyta blight symptoms on field peas (Pisum sativum) in South Australia

© 2009 by The Mycological Society of AmericaPhoma koolunga sp. nov. is described, having been isolated from ascochyta blight lesions on field pea (Pisum sativum) in South Australia. The species is described morphologically and sequences of the internal transcribed spacer region compared with those of the accepted pathogens causing ascochyta blight of field peas. P. koolunga was distinct from Mycosphaerella pinodes (anamorph: Ascochyta pinodes), Phoma medicaginis var. pinodella and Ascochyta pisi. Under controlled conditions the symptoms on pea seedlings caused by P. koolunga were indistinguishable from those caused by M. pinodes, other than a 24 h delay in disease development. Isolates of P. koolunga differed in the severity of disease caused on pea seedlings.J.A. Davidson, D. Hartley, M. Priest, M. Krysinska-Kaczmarek, Herdina, A. McKay and E.S. Scot

Distribution and survival of ascochyta blight pathogens in field-pea-cropping soils of Australia

Phoma koolunga, Didymella pinodes, and P. medicaginis var. Pinodella were detected in DNA extracted from soil following field pea crops across four states in the southeastern and western regions of Australia. P. koolunga was commonly detected in soil from South Australia but rarely in other states whereas D. pinodes plus P. medicaginis var. Pinodella were widespread in all regions tested. The quantity of DNA of these pathogens detected in soils prior to growing field pea was positively correlated with ascochyta blight lesions on field pea subsequently grown in infested soil in a pot bioassay and also on field pea in naturally infected field trials. The quantity of DNA of the soilborne pathogens was greatest following a field pea crop and gradually decreased in the following 3 years. The DNA tests were used to quantify the DNA of the pathogens in field pea plants sampled from naturally infected field trials in South Australia over two seasons. The combined results of DNA tests and pathogen isolation from the plants indicated that P. koolunga and D. pinodes were equally responsible for the ascochyta blight symptoms in the diseased trials, while P. Medicaginis var. pinodella had a minor role in the disease complex.J. A. Davidson, M. Krysinska-Kaczmarek, C. J. Wilmshurst, A. McKay, Herdina and E. S. Scot

Toward routine, DNA-based detection methods for marine pests

Marine pest incursions can cause significant ongoing damage to aquaculture, biodiversity, fisheries habitat, infrastructure and social amenity. They represent a significant and ongoing economic burden. Marine pests can be introduced by several vectors including aquaculture, aquarium trading, commercial shipping, fishing, floating debris, mining activities and recreational boating. Despite the inherent risks, there is currently relatively little routine surveillance of marine pest species conducted in the majority of countries worldwide. Accurate and rapid identification of marine pest species is central to early detection and management. Traditional techniques (e.g. physical sampling and sorting), have limitations, which has motivated some progress towards the development of molecular diagnostic tools. This review provides a brief account of the techniques traditionally used for detection and describes developments in molecular-based methods for the detection and surveillance of marine pest species. Recent advances provide a platform for the development of practical, specific, sensitive and rapid diagnosis and surveillance tools for marine pests for use in effective prevention and control strategies.Nathan J. Bott, Kathy M. Ophel-Keller, Michael T. Sierp, Herdina, Keith P. Rowling, Alan C. McKay, Maylene G. K. Loo, Jason E. Tanner and Marty R. Devene