Thatch biodegradation and antifungal activities of two lignocellulolyticStreptomycesstrains in laboratory cultures and in golf green turfgrass

2000 ◽  
Vol 46 (6) ◽  
pp. 550-558 ◽  
Author(s):  
Karen Chamberlain ◽  
Don L Crawford
Keyword(s):  
Carbon Sources ◽  
Fungal Growth ◽  
Dry Weight ◽  
Field Studies ◽  
Water Soluble ◽  
Streptomyces Spp ◽  
Fungal Populations ◽  
Streptomyces Violaceusniger

The use of lignocellulolytic Streptomyces spp. as biological agents, to enhance thatch degradation in turf and to slow its rate of accumulation while controlling fungal growth in the thatch layer, was studied. In flask scale studies, two lignocellulolytic Streptomyces violaceusniger (= hygroscopicus) strains (YCED9 and WYE53) decomposed thatch (>30% dry weight) over a 12-week incubation period. Biodegradation was accompanied by production of extracellular cellulases, xylanases, and peroxidases. The accumulation of the polymeric, water-soluble lignin degradation intermediate acid, precipitable polymeric lignin (APPL), was also observed. Residual thatch from 12-week-old cultures had an increased lignin-to-carbohydrate ratio, an indication that although lignin was metabolized, carbohydrates were preferential carbon sources for these actinomycetes. A spore-containing soluble dry powder formulation was used as an inoculum in an in situ field experiment. This formulation was maintained in storage at 4°C for over two years without viability loss. Results from the golf green experiment showed that although treated thatch layers in established greens were not appreciably reduced over the course of one summer, the Streptomyces were active and maintained their populations within the thatch, while fungal growth was suppressed as compared to controls. The results show that treatment of turfgrass with these Streptomyces may be useful for the long-term control of fungal populations within the thatch. Longer field studies are required to assess the long-term potential for also controlling thatch build-up and fungal pathogens.Key words: biocontrol, biodegradation, fungi, Streptomyces, thatch.

Differential Response of Hemp Dogbane (Apocynum cannabinum) to Clopyralid, Dowco 433, and 2,4-D

1991 ◽  
Vol 5 (4) ◽  
pp. 782-788 ◽  
Author(s):  
Michael S. Orfanedes ◽  
Loyd M. Wax
Keyword(s):  
Vegetative Growth ◽  
Growth Stage ◽  
Good Control ◽  
Dry Weight ◽  
Field Studies ◽  
Differential Response ◽  
Treatment Control ◽  
Short And Long Term ◽  
Late Application

Field studies were conducted to compare the short- and long-term control of hemp dogbane by POST applications of Dowco 433, clopyralid, and 2,4-D amine. Dowco 433 at 140 g ae ha–1controlled 81 to 93% of weeds at 8 wk after treatment. Good control (79 to 89%) was also achieved with 560 g ae ha–12,4-D amine at 8 wk after treatment. Twelve months after treatment, control of hemp dogbane averaged 65 to 75% where Dowco 433 was applied at rates of 140 g ha–1or higher. Similar results were obtained with 2,4-D amine at 560 g ha–1. Control with clopyralid was minimal. Weed height and dry weight were reduced with all treatments except clopyralid. The effect of early versus late application was also evaluated in two studies. In certain situations, control 8 wk after treatment was greater when application was made during the early reproductive growth stage as opposed to the vegetative growth stage.

scholarly journals Nano- and microplastics affect the composition of freshwater benthic communities in the long term

2020 ◽  
Vol 6 (5) ◽  
pp. eaay4054 ◽  
Author(s):  
P. E. Redondo-Hasselerharm ◽  
G. Gort ◽  
E. T. H. M. Peeters ◽  
A. A. Koelmans
Keyword(s):  
Risk Assessment ◽  
Community Composition ◽  
Benthic Communities ◽  
Dry Weight ◽  
Community Effects ◽  
Positive Effects ◽  
Population Sizes ◽  
Over Time

Given the societal concern about the presence of nano- and microplastics in the environment, our nescience with respect to in situ effects is disturbing. Data on long-term implications under ecologically realistic conditions are particularly important for the risk assessment of nano- and microplastics. Here, we evaluate the long-term (up to 15 months) effects of five concentrations of nano- and microplastics on the natural recolonization of sediments by a macroinvertebrate community. Effects were assessed on the community composition, population sizes and species diversity. Nano- and microplastics adversely affected the abundance of macroinvertebrates after 15 months, which was caused by a reduction in the number of Naididae at the highest concentration (5% plastic per sediment dry weight). For some other taxa, smaller but still significant positive effects were found over time, altogether demonstrating that nano- and microplastics affected the community composition.

Increased Kernel Number in Norin 10-Derived Dwarf Wheat: Evaluation of the Cause

1986 ◽  
Vol 13 (6) ◽  
pp. 767 ◽  
Author(s):  
RA Fischer ◽  
YM Stockman
Keyword(s):  
Spring Wheat ◽  
Dry Matter ◽  
Dry Weight ◽  
Field Studies ◽  
Water Soluble ◽  
Growth Potential ◽  
Soluble Carbohydrate ◽  
Floral Initiation ◽  
Kernel Number ◽  
Shoot Dry Weight

This study of the effect of major Norin 10 dwarfing genes (Rht1, Rht2) on kernel number in spring wheat emphasised three near-isogenic pairs of spring wheat, differing in the presence or absence of both genes. Plants were grown under controlled environment conditions with equal light intensities at their tops and were restricted to main stems by repeated tiller trimming. The dwarf wheats had a higher proportion of shoot dry weight in the spike at anthesis, an effect which field studies suggest is closely associated with their production of more kernels per unit land area. Stems of dwarf genotypes were somewhat shorter as early as 50 days before anthesis (i.e. before floral initiation) but relative differences became especially great commencing at 35 days before anthesis. Apex and spike lengths were never very different. A greater proportion of dry matter was distributed to leaf lamina from 50 days before anthesis until the end of lamina growth in dwarf wheats, while partitioning to stems was lower from 50 days before anthesis onwards. Partitioning to spikes was only higher in the 15 days preceding anthesis. Stem water-soluble carbohydrate (WSC) contents at anthesis were greater in dwarf wheats but maximum spike WSC contents reached at about 15 days before anthesis were lower. Spike morphogenesis including floret production and grain setting did not differ generally, except for a tendency with dwarf wheats for a longer floral initiation to anthesis interval and for more kernels per unit of spike weight at anthesis. The major unique feature of dwarf genotypes, the higher proportion of dry matter partitioned to the spike, appeared to be due to reduced competition from growing stems in dwarf wheats rather than intrinsic differences in the growth potential of their spikes.

scholarly journals Long-term effects of an iron heater and Äspö groundwater on smectite clays: Chemical and hydromechanical results from the in situ alternative buffer material (ABM) test package 2

Clay Minerals ◽  
2016 ◽  
Vol 51 (2) ◽  
pp. 129-144 ◽  
Author(s):  
Sirpa Kumpulainen ◽  
Leena Kiviranta ◽  
Petri Korkeakoski
Keyword(s):  
Radioactive Decay ◽  
Swelling Pressure ◽  
Water Soluble ◽  
Exchangeable Cation ◽  
Long Term Effects ◽  
Buffer Material ◽  
Soluble Sulfate ◽  
Heating Test

AbstractSmectite-rich clays are to be used in nuclear repositories for sealing in the radioactive waste. As the radioactive decay produces heat it may affect the chemical, physical and hydromechanical properties of the clay components in the repository. An ‘alternative buffer material’ (ABM) experiment is a Svensk Kärnbränslehantering AB (SKB)-led in situ heating test placed in boreholes in the Äspö tunnel (Sweden). The 2nd ABM package was dismantled in April 2013, after 6.5 y of equilibration with Äspö groundwater and 5 y of heating. The objective was to investigate the long-term effects of the iron heater and Äspö groundwater on four of 31 compacted blocks made of MX-80, Deponit CaN and Friedland clays.Compared to the starting materials, major changes in the exchangeable cation populations were observed. Within horizontal profiles, water-soluble sulfate, Ca, K and Mg increased; poorly crystalline Fe oxide contents decreased; total Mg, Ca and S increased; and a decrease in the amounts of total Na and K away from the host rock towards the heater was observed. At the boundary with the heater, an increase in the total Fe content, decreases in total Si and Al contents, precipitation of gypsum and anhydrite, dissolution of cristobalite and feldspars, and indications of the formation of trioctahedral clay minerals were observed. A decrease in swelling pressure for the Friedland clay (in drill-cored samples) was recorded which was recovered after grinding and recompaction. No effects of hydraulic conductivity were found, after 6.5 y of reaction time, in the subsurface of any of materials studied.

scholarly journals Void conditions and potential for mould growth in insulated and uninsulated suspended timber ground floors

2019 ◽  
Vol 37 (4) ◽  
pp. 395-425
Author(s):  
Sofie Pelsmakers ◽  
Evy Vereecken ◽  
Miimu Airaksinen ◽  
Cliff C.A. Elwell
Keyword(s):  
Fungal Growth ◽  
Primary Data ◽  
Current Evidence ◽  
Extensive Literature ◽  
Mould Growth ◽  
Content Type ◽  
The Uk ◽  
Global Evidence

PurposeMillions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the effect of insulating such floors. Upgrading floors changes the void conditions, which might increase or decrease moisture build-up and mould and fungal growth. The purpose of this paper is to provide a review of the current global evidence and present the results ofin situmonitoring of 15 UK floor voids.Design/methodology/approachAn extensive literature review on the moisture behaviour in both uninsulated and insulated suspended timber crawl spaces is supplemented with primary data of a monitoring campaign during different periods between 2012 and 2015. Air temperature and relative humidity sensors were placed in different floor void locations. Where possible, crawl spaces were visually inspected.FindingsComparison of void conditions to mould growth thresholds highlights that a large number of monitored floor voids might exceed the critical ranges for mould growth, leading to potential occupant health impacts if mould spores transfer into living spaces above. A direct comparison could not be made between insulated and uninsulated floors in the sample due to non-random sampling and because the insulated floors included historically damp floors. The study also highlighted that long-term monitoring over all seasons and high-resolution monitoring and inspection are required; conditions in one location are not representative of conditions in other locations.Originality/valueThis study presents the largest UK sample of monitored floors, evaluated using a review of current evidence and comparison with literature thresholds.

scholarly journals Separating and Characterizing Functional Nitrogen Degraders via Magnetic Nanoparticle-Mediated Isolation

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Yujiao Sun ◽  
Meng Yin ◽  
Danyang Zheng ◽  
Lei Wang ◽  
Xiaohui Zhao ◽  
...  
Keyword(s):  
Redundancy Analysis ◽  
Magnetic Nanoparticle ◽  
Carbon Sources ◽  
Ammonia Nitrogen ◽  
Term Treatment ◽  
In Situ Conditions ◽  
Long Term Treatment ◽  
Ammonia Degradation

Magnetic nanoparticle-mediated isolation (MMI) is a new method for isolating active functional microbes from complex microorganisms without substrate labeling. In this study, the composition and properties of magnetic nanoparticles (MNPs) were characterized by a number of techniques, indicating that MNPs have characteristics such as microinterfaces and can be efficiently fixed on the surface of microbial cells. It also introduced the MMI technology in activated sludge after stable long-term treatment. With further addition of promotor carbon sources, the enrichment of the functional nitrogen degraders in MMI was significantly higher than in samples without MNPs, showing the advantages of MMI in identifying the active degraders. Redundancy analysis (RDA) also showed that the functional nitrogen degraders such as Comamonadaceae_unclassified and Thiobacillus absolutely dominated in situ ammonia degradation, and the change in dominant genera had the same trend as the degradation rate of ammonia nitrogen. In the magnetically functionalized system, the separated functional nitrogen degraders significantly improved ammonia nitrogen degradation efficiency, making it basically stable at more than 80%, up to 91.6%. These results prove that the complex flora created after the addition of MNPs is more adaptable to newly introduced pollutants, and MMI is a powerful tool for studying pollutant-degrading microorganisms under in situ conditions.

scholarly journals Use of deproteinised leaf juice of Medicago sativa L. for the production of α-amylase

2019 ◽  
Vol 26 ◽  
pp. 7-14
Author(s):  
S Iliyas
Keyword(s):  
Medicago Sativa ◽  
Spinacia Oleracea ◽  
Fungal Growth ◽  
Dry Weight ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
Simultaneous Increase ◽  
Anethum Graveolens ◽  
Vitamin B9 ◽  
Leaf Juice

Leaf protein concentration (LPC) is a good source of cyanocobalamine (B12), ascorbic acid (vitamin C) and folic acid (vitamin B9). After isolation of LPC from leaves the remaining by product is deproteinised leaf juice (DPJ) which is rich in water soluble carbohydrates, free amino acids, minerals, lipids and vitamins. The dry matter (DM) and nutrient composition of DPJ varies from species to species. The DM content in this fraction was found between 1.2 to 4.0%. Six fungi were grown on the DPJ expressed from Medicago sativa, Anethum graveolens, Spinacia oleracea, Trigonella foenium-graecum, Coriandrum sativum and also on conventional GN medium to evaluate the suitability of DPJ as a medium for fungal growth and subsequent production of ∝-amylase. The efficiency of DPJ as a medium for fungal growth was evaluated and its value in microbial biotechnology for the production of ∝-amylase was tested. Increase in concentrate of flour in the DPJ there was simultaneous increase in the mycelial dry weight (MDW) production of the six fungi under investigation. On DPJ alone, the yield of MDW was between 76.0 and 89.5 mg which increased to 164.5, 131.0 and 117.0 mg respectively under the influence of the flours of wheat, sorghum and maize respectively. Maximum response to the enrichment of DPJ by flour was noticed with A. niger. As with the increase in growth of fungi with increasing concentration of flour, the activity of amylase also increased. On an average it was 34 - 96 U/ml when the fungi were grown on DPJ alone, which increased to 301, 265 and 276 U/ml under the influence of flours. J. bio-sci. 26: 07-14, 2018

scholarly journals Bell Pepper Seedling Growth and Yield following Pretransplant Nutritional Conditioning

HortScience ◽  
1994 ◽  
Vol 29 (9) ◽  
pp. 999-1001 ◽  
Author(s):  
Robert J. Dufault ◽  
Jonathan R. Schultheis
Keyword(s):  
Seedling Growth ◽  
Total Yield ◽  
Dry Weight ◽  
Field Studies ◽  
Bell Pepper ◽  
Growth And Yield ◽  
Yield And Quality ◽  
Transplant Shock ◽  
Bell Peppers

To reduce transplant shock of bell peppers (Capsicum annuum L.), we tested the effectiveness of pretransplant nutritional conditioning (PNC) as a promoter of earliness and yield. In Expt. 1, `Gatorbelle' bell pepper seedlings were fertilized with N from Ca(NO3)2 at 25, 75, or 225 mg·liter-1 and P from Ca(H2PO4)2 at 5, 15, or 45 mg·liter-1. Nitrogen interacted with P, affecting shoot fresh and dry weight, leaf area, root dry weight, seedling height, and leaf count. In Expt. 2, transplants conditioned with N from 50, 100, and 200 mg·liter-1 and P at 15, 30, and 60 mg·liter-1 were field-planted in Charleston, S.C., and Clinton, N.C. Nitrogen- and P-PNC did not greatly affect recovery from transplant shock. Although N- and P-PNC affected seedling growth in the greenhouse, earliness, total yield, and quality were similar in field studies among all PNC treatments at both locations. PNC with 50 mg N and 15 mg P/liter can be used with this variety and not have any long-term detrimental effects on yield and quality.

Rapid increases in respiratory epithelial permeability occur after intratracheal instillation of PMA

1987 ◽  
Vol 63 (1) ◽  
pp. 292-301 ◽  
Author(s):  
B. R. Pitt ◽  
J. S. Cole ◽  
P. Davies ◽  
C. N. Gillis
Keyword(s):  
Hydrogen Peroxide ◽  
Rate Constants ◽  
Intratracheal Instillation ◽  
Dry Weight ◽  
Water Soluble ◽  
Epithelial Permeability ◽  
Pulmonary Epithelial Permeability ◽  
Production Of Hydrogen ◽  
Respiratory Epithelial

We measured pulmonary epithelial permeability by quantifying the disappearance of two water-soluble compounds, [14C]mannitol and [3H]inulin, after their instillation, with and without phorbol myristate acetate (PMA), into gas-filled perfused (50 ml/min) rabbit lungs in situ. Both tracers disappeared in a monoexponential fashion over 30 min with calculated first-order rate constants (control; n = 11) of 0.0008 +/- 0.0002 and 0.0027 +/- 0.0008 min-1 for inulin and mannitol, respectively. The ratio of the rate constants (3.1 +/- 0.5) was not significantly different from the ratio of diffusivities of mannitol:inulin (3.7). Addition of PMA (250 micrograms) significantly (n = 9, P less than 0.05) increased the rate constants for both inulin and mannitol to 0.0024 +/- 0.0007 and 0.0087 +/- 0.0025 min-1, respectively, while not affecting their ratio (4.3 +/- 0.5). Addition of human leukocytes (4–8 X 10(8)/l) to the perfusate did not exacerbate the effect of 250 micrograms PMA (n = 3). The addition of catalase (n = 7) completely inhibited the effect of 250 micrograms PMA. PMA (250 micrograms) did not significantly affect perfusion pressure but increased wet-to-dry weight ratios. Light microscopic histology showed damage to epithelial and endothelial cells after 250 micrograms PMA which was not seen after coinstillation of catalase. Catalase sensitivity of functional and structural effects of PMA suggests that the effect was secondary to production of hydrogen peroxide. Since this effect was noted in lungs not perfused with neutrophils and addition of leukocytes did not exacerbate the increase in permeability, we hypothesize that an undetermined pulmonary cell type was the source of hydrogen peroxide. Finally, we found no evidence for restrictive pores with radii of 0.4–1.4 nm.

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