Status Dan Keanekaragaman Fungi Mikoriza Arbuskula (FMA) Pada Lahan Produktif Dan Lahan Non Produktif

Existence and status of the AMF is influenced by biotic and abiotic factors. This research aims to study and know the status and existence of Arbuscule Mycorrhizal Fungi (AMF) on the land productive and non productive land. Soil samples derived from the productive and non productive land in Tanjung Anom. This research uses the filter to get the spores and staining method to determine root colonization. Results showed that AMF colonization in productive land obtained 17.83% with an average density of 80 spores / 50g soil, and the percent of AMF colonization in non productive land obtained 42.76% with an average density of 89 spores / 50g soil. AMF spore types Glomus and Acaulospora on productive land obtained 13 spore types Glomus sp, and on non productive land obtained 14 spore types Glomus sp and 2 Acaulospora spore types. Total spore types were obtained 27 spore types, 25 types of spores Glomus sp and 2 Acaulospora sp spore types

Organic amendment increases arbuscular mycorrhizal fungal diversity in primary coastal dunes

Plastic pots were inserted beneath seedlings of a shallow-rooted C4 grass species, Ischaemum indicum, with and without a root-impenetrable nylon sachet filled with organic matter (OM) amendment, at seven stations along an interrupted belt transect in which plant community and soil chemistry had been previously surveyed. The transect was perpendicular to mean high-water mark (MH-WM) across a primary coastal dune system in Goa, India, where summer monsoon is the predominant weather feature. The Quadrat survey of plant frequency was made in stations when the above-ground biomass was estimated to be highest. Arbuscular mycorrhiza fungal (AMF) spore density and diversity were determined morphologically in amended and control pots soils, and in OM sachet residues, after host-plant desiccation when monsoon rains had ceased. Twenty-seven AM fungal spore morphotypes were isolated from the pots containing OM amended rhizosphere soils, 19 from controls and 14 from OM residues in the sachets. Gigaspora margarita proved to be the dominant spore in all treatments. Eight morphotypes recovered from amended pots were not recovered from the controls. There was an increasing trend in species diversity in amended pots away from MH-WM. Spore recovery from the three regimes showed variable distribution that indicated differing AMF species strategies

Asexual and sexual replication in sporulating organisms

This paper develops models describing asexual and sexual replication in sporulating organisms. Replication via sporulation is the replication strategy for all multicellular life, and may even be observed in unicellular life (such as with budding yeast). We consider diploid populations replicating via one of two possible sporulation mechanisms: (1) Asexual sporulation, whereby adult organisms produce single-celled diploid spores that grow into adults themselves. (2) Sexual sporulation, whereby adult organisms produce single-celled diploid spores that divide into haploid gametes. The haploid gametes enter a haploid "pool", where they may recombine with other haploids to form a diploid spore that then grows into an adult. We consider a haploid fusion rate given by second-order reaction kinetics. We work with a simplified model where the diploid genome consists of only two chromosomes, each of which may be rendered defective with a single point mutation of the wild-type. We find that the asexual strategy is favored when the rate of spore production is high compared to the characteristic growth rate from a spore to a reproducing adult. Conversely, the sexual strategy is favored when the rate of spore production is low compared to the characteristic growth rate from a spore to a reproducing adult. As the characteristic growth time increases, or as the population density increases, the critical ratio of spore production rate to organism growth rate at which the asexual strategy overtakes the sexual one is pushed to higher values. Therefore, the results of this model suggest that, for complex multicellular organisms, sexual replication is favored at high population densities, and low growth and sporulation rates.Comment: 8 pages, 5 figures, to be submitted to Journal of Theoretical Biology, figures not included in this submissio

Uji Pengaruh Beberapa Herbisida Terhadap Trichoderma SP Secara in Vitro

In Vitro Test on the Effect of Some Herbicides Application towards Trichoderma sp. This research\u27sobjective is to study effect of herbicide ingredient with different concentration to growth of myceliumcolony and spore density of Trichoderma sp. Trichoderma sp was inoculated in PDA which havebeen added with six different herbicide ingredients, there are paraquat, glyphosate, fenoxaprop-ethyl,triclopyr, 2,4D, and fluroxypyr at three different concentrations, there are 100%, 75%, and 50% fromrecommended concentration. This research was conducted from May until October 2013 atPhytopathology Laboratory, Agriculture Faculty, University of Sumatera Utara, by using factorialcompletely randomized design with three replications. The result have showed that highest extensiveof mycelium colonywas observed at fluroxypyr 50% concentration, meanwhile the lowest extensive ofmycelium colony was observed at glyphosate 50% concentration. Highest spore density wasobservedat fluroxypyr 50% concentration , meanwhile the lowest spore density was observed at paraquat 100%concentration. Herbicide ingredient interaction with concentration of herbicide very significantlyaffected growth of mycelium colony and spore density of Trichoderma sp

Patogenisitas Jamur Karat (Puccinia Philippinensis Syd.), Pada Gulma Teki (Cyperus Rotundus L.)

The pathogenicity of a rust fungus (Puccinia philippinensis Syd.), on purple nutsedges (Cyperus rotundus L.). A research aimed at understanding the pathogenicity of a rust fungus (Puccinia philippinensis Syd.), a potential biological control agent of purple nutsedges (Cyperus rotundus L.) had been conducted in a glasshouse of Faculty of Agriculture the University of Mataram. These factorial experiments designed according to Randomized Completely Design (CRD) and consisted of spore density and time of application. Spore density treatments consisted of 0, 5000, 10 000, 15 000, 20 000, 25 000, or 30 000 spore/mL applied either in the morning or in the afternoon. The results showed that the higher the spore density, the higher the number of pustules formed, the higher the disese intensity, and the faster the disease progressed. Urediniospores applied in the afternoon produced more pustules, higher disease intensity, and faster disease progression compare to those applied in the morning

The fate of the missing spores

It is well-known that many species with small diaspores can disperse far during extended temporal scales (many years). However, studies on short temporal scales usually only cover short distances (in, e.g., bryophytes up to 15 m). By using a novel experimental design, studying the realized dispersal, we extend this range by almost two orders of magnitude. We recorded establishment of the fast-growing moss Discelium nudum on introduced suitable substrates, placed around a translocated, sporulating mother colony. Around 2,000 pots with acidic clay were placed at different distances between 5 m and 600 m, in four directions, on a raised bog, with increased pot numbers with distance. The experiment was set up in April-May and the realized dispersal (number of colonized pots) was recorded in September. Close to the mother colony (up to 10 m), the mean colonization rates (ratio of colonized pots) exceeded 50%. At distances between 10 and 50 m colonization dropped sharply, but beyond 50 m the mean colonization rates stabilized and hardly changed (1-3%). The estimated density of spores causing establishments at the further distances (2-6 spores/m2) was realistic when compared to the estimated spore output from the central colonies. Our study supports calculations from earlier studies, limited to short distances, that a majority of the spores disperse beyond the nearest vicinity of a source. The even colonization pattern at further distances raises interesting questions about under what conditions spores are transported and deposited. However, it is clear that regular establishment is likely at the km-scale for this and many other species with similar spore output and dispersal mechanism

Separation of bacterial spores from flowing water in macro-scale cavities by ultrasonic standing waves

The separation of micron-sized bacterial spores (Bacillus cereus) from a steady flow of water through the use of ultrasonic standing waves is demonstrated. An ultrasonic resonator with cross-section of 0.0254 m x 0.0254 m has been designed with a flow inlet and outlet for a water stream that ensures laminar flow conditions into and out of the resonator section of the flow tube. A 0.01905-m diameter PZT-4, nominal 2-MHz transducer is used to generate ultrasonic standing waves in the resonator. The acoustic resonator is 0.0356 m from transducer face to the opposite reflector wall with the acoustic field in a direction orthogonal to the water flow direction. At fixed frequency excitation, spores are concentrated at the stable locations of the acoustic radiation force and trapped in the resonator region. The effect of the transducer voltage and frequency on the efficiency of spore capture in the resonator has been investigated. Successful separation of B. cereus spores from water with typical volume flow rates of 40-250 ml/min has been achieved with 15% efficiency in a single pass at 40 ml/min.Comment: 11 pages, 6 figure

Determining whether estimated spore release rates for Aspergillus fumigatus are compatible with their measured growth rates in composting systems

The composting process like other waste management activities has the potential to generate large concentrations of bioaerosols which can be widely dispersed into the surrounding environment. There has been considerable interest in the literature of the effect of bioaerosols and in particular Aspergillus fumigatus on the health of plant operators and those living in close proximity to composting plants (Olver, 1994; Fischer et al., 1999; Fischer et al., 2000; Bunger et al., 200). Although bioaerosols can be generated through a range of operational procedures it has also been suggested that large numbers of Aspergillus fumigatus spores can be emitted from static compost piles through the action of natural air movements across the surface of the biodegrading material. Through the use of a portable wind tunnel apparatus researchers have determined the rate of emission of Aspergillus fumigatus spores as a result of air movement across the surface of the material (Taha et al., 2004; 2005; 2006 & 2007). The aim of this work was to use controlled laboratory experiments using compost samples and Aspergillus fumigatus spores to determine the sporulation rate of Aspergillus fumigatus. Using this data it would then be possible to verify whether bioaerosol emission rates from static compost windrows calculated and quoted in the literature can in fact be maintained over longer time periods. A series of experiments were carried out using Aspergillus fumigatus spores on agar plates and small samples of green waste compost to determine the number of spores that could be generated by each existing spore over a seven day period. From the experiments the sporulation rate determined from the agar plates varied with averages of either 4.48x104 or 2.83 spores/day depending upon the date set used and from the compost experiments it was 1.33 spores/day. Using this data and making a number of assumptions for moisture content (50%), bulk density (650 kg/m3) and the wind penetration depth (10-25mm) the potential release rates were calculated. The data from the agar experiments yielded a potential release rate at 10mm up to 5 orders of magnitude in excess of that quoted by Taha et al. (2004 & 2005. Using the trimmed data set the agar release figures are between 6.17 x 103 and 1.23 x 104 cfu/m2/s depending upon the wind penetration depth used and are comparable to those quoted in the literature. The release rate calculated using the compost experiments was slightly lower than the agar 2 data and consequently the release rates even at a wind penetration depth of 25mm are just outside the range quoted by Taha et al. (2004 & 2005). Although the data presented in this paper were determined from controlled laboratory experiments they show that it is possible for Aspergillus fumigatus to generate spores at a sufficient rate to allow the release of significant numbers of spores. The calculated sporulation rates would allow spores to be released at the rates quoted in the literature and suggest that the fugitive release rates quoted in the literature would be able to be maintained over long periods of time. However it is recognised that the data is affected greatly by the assumptions one makes, in particular the existing concentration of Aspergillus fumigatus. Despite the limitations the original intention of the work was to attempt to establish the long term applicability of the fugitive release rates for Aspergillus fumigatus from green waste compost quoted in the literature and it has achieved this objective