Epidemiological Studies, viz. Effect Of Soil Temperature, Moisture, Electrical Conductivity (EC), Soil pH on Sclerotium rolfsii Sacc. Causing Sclerotium Wilt or Rot in Potato and Its Survival and Host Range

Guav a cv . Allahabad Safeda w as grown in saline soils and irrigated with the best av ailable w ater -1 -1 + -1 (EC 2.8 dS m ). Based on chemical composition (pH- 7.1, EC - 2.8 dS m , Na - 20.04 meq l and IW IW sodium adsorption ratio- 4.86), irrigation w ater w as categorized as marginally saline. The soil pH 2 -1 w as mostly below 8.5 but mean electrical conductivity (EC ) v alues ranged from 0.5-2 dS m 2 indicating moderate to high salinity in the experimental soil. After one-y ear of experimentation, fiv e plants randomly selected from each treatment and the data w ere recorded. Plant height -1 -1 significantly increased (LSD 5%) with increase in salinity from 0.5 dS m to 1.4 dS m . A similar -1 trend w as noted with respect to stem girth. The av erage plant height at 0.5, 0.9 and 1.4 dS m salinity lev els w as 98.3 cm, 108.3 cm and 123 cm, respectiv ely whereas the corresponding stem girth v alues -1 w ere 2.24 cm, 2.28 cm and 2.46 cm. At 2 dS m salinity ,how ev er , both av erage plant height (94.6 cm) and stem girth (2.24 cm) significantly decreased and w ere found to be comparable to control (0.5 dS -1 + -1 m ) v alues. Plants show ed negligible Na accumulation in leav es up to 1.4 dS m salinity , but -1 + exposure to elev ated salinity (2 dS m ) significantly increased leaf Na (0.16% DW). These data -1 indicated a salinity tolerance (EC )threshold of about 1.5 dS m inguav a cultiv ar Allahabad Safeda.

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Soil greenhouse gas fluxes from different tree species on Taihang Mountain, North China

Biogeosciences ◽

10.5194/bg-11-1649-2014 ◽

2014 ◽

Vol 11 (6) ◽

pp. 1649-1666 ◽

Cited By ~ 17

Author(s):

X. P. Liu ◽

W. J. Zhang ◽

C. S. Hu ◽

X. G. Tang

Keyword(s):

Soil Moisture ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Soil Temperature ◽

Soil Ph ◽

Tree Species ◽

Soil Bulk Density ◽

Total N ◽

Gas Fluxes ◽

Greenhouse Gas Fluxes

Abstract. The objectives of this study were to investigate seasonal variation of greenhouse gas fluxes from soils on sites dominated by plantation (Robinia pseudoacacia, Punica granatum, and Ziziphus jujube) and natural regenerated forests (Vitex negundo var. heterophylla, Leptodermis oblonga, and Bothriochloa ischcemum), and to identify how tree species, litter exclusion, and soil properties (soil temperature, soil moisture, soil organic carbon, total N, soil bulk density, and soil pH) explained the temporal and spatial variation in soil greenhouse gas fluxes. Fluxes of greenhouse gases were measured using static chamber and gas chromatography techniques. Six static chambers were randomly installed in each tree species. Three chambers were randomly designated to measure the impacts of surface litter exclusion, and the remaining three were used as a control. Field measurements were conducted biweekly from May 2010 to April 2012. Soil CO2 emissions from all tree species were significantly affected by soil temperature, soil moisture, and their interaction. Driven by the seasonality of temperature and precipitation, soil CO2 emissions demonstrated a clear seasonal pattern, with fluxes significantly higher during the rainy season than during the dry season. Soil CH4 and N2O fluxes were not significantly correlated with soil temperature, soil moisture, or their interaction, and no significant seasonal differences were detected. Soil organic carbon and total N were significantly positively correlated with CO2 and N2O fluxes. Soil bulk density was significantly negatively correlated with CO2 and N2O fluxes. Soil pH was not correlated with CO2 and N2O emissions. Soil CH4 fluxes did not display pronounced dependency on soil organic carbon, total N, soil bulk density, and soil pH. Removal of surface litter significantly decreased in CO2 emissions and CH4 uptakes. Soils in six tree species acted as sinks for atmospheric CH4. With the exception of Ziziphus jujube, soils in all tree species acted as sinks for atmospheric N2O. Tree species had a significant effect on CO2 and N2O releases but not on CH4 uptake. The lower net global warming potential in natural regenerated vegetation suggested that natural regenerated vegetation were more desirable plant species in reducing global warming.

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Vertical distribution of soil nutrients under different land use systems in Bangladesh

Journal of Aridland Agriculture ◽

10.25081/jaa.2020.v6.6438 ◽

2020 ◽

pp. 6-12

Author(s):

Tahsina Sharmin Hoque ◽

Shafia Afrin ◽

Israt Jahan ◽

Md. Joinul Abedin Mian ◽

Mohammad Anwar Hossain

Keyword(s):

Electrical Conductivity ◽

Land Use ◽

Organic Matter ◽

Soil Ph ◽

Soil Depth ◽

Organic Matter Content ◽

Soil Samples ◽

Water Soluble ◽

Exchangeable K ◽

Land Use Systems

Soil depth can significantly influence the availability of nutrients in soil. An experiment was conducted with seven soil samples from seven land use types to observe the effect of soil depth on soil properties under various land use systems. Soil pH, electrical conductivity (EC), organic matter, available phosphorus (P), available sulphur (S) and different forms of potassium (K) such as water soluble, exchangeable and non-exchangeable were determined from the soil samples collected from four soil depths (viz. 0-10, 10-20, 20-30 and 30-40 cm). Soil pH varied from 6.30-7.39 irrespective of depths and land uses and it increased with increasing soil depth. Electrical conductivity of the soils ranged from 42-310 µS cm-1 and organic matter status of most of the soils was very low to medium in level. Both EC and organic matter content decreased with the increase of soil depth. Available P concentration showed no specific changing trend with soil depth whereas available S concentration under different land use systems decreased with increasing soil depth. The concentrations of water soluble, exchangeable and non-exchangeable K in soils varied from 12.30-39.60, 20.90-53.16 and 163.30-684.30 mg kg-1, respectively and showed no specific changing pattern with soil depth. Water soluble K content was higher in rice growing fertilizer and manure-treated soil but higher exchangeable and non-exchangeable K contents were observed in banana growing soil. In rice growing soils, nutrient concentration is mostly higher in nitrogen (N), P and K + farm yard manure (FYM) - treated plots compared to rice growing control plots.

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Ground vegetation diversity and geobotanical analysis in dune pine forests in southwest Estonia

Forestry Studies / Metsanduslikud Uurimused ◽

10.2478/fsmu-2018-0012 ◽

2018 ◽

Vol 69 (1) ◽

pp. 63-74 ◽

Cited By ~ 1

Author(s):

Mari Tilk ◽

Katri Ots ◽

Tea Tullus ◽

Malle Mandre

Keyword(s):

Electrical Conductivity ◽

Species Richness ◽

Species Composition ◽

Water Content ◽

Soil Ph ◽

Vascular Plant ◽

Lichen Species ◽

Ground Vegetation ◽

Light Conditions ◽

Vegetation Species

Abstract To investigate the ecosystems on dunes, five typical dunes were selected in the coastal area of the Baltic Sea in southwest Estonia. To study ground vegetation species richness, species composition and horizontal structure, 251 quadrats of 1 m2 in size were established and descriptions of vascular plants, bryophytes and lichen species were provided. Topographical factors, soil horizons, soil pH and electrical conductivity, soil nutrients, soil moisture conditions and light conditions were determined. In total, 42 vascular plant, 43 bryophyte and 48 lichen species were recorded on five dunes. Vascular plant species richness and composition on forested dunes was dependent on the absolute dune height, zone and aspect of the slope, soil nitrogen, potassium and phosphorus content, soil pH and moisture, the cover of the bryophyte-lichen layer and light conditions. Regarding bryophyte and lichen layer species composition, important factors were the aspect of the dune, vascular plant species cover, light conditions, the thickness of the moderately decomposed organic soil horizon, soil pH, electrical conductivity and volumetric water content. Lichen species richness was highest on the slopes of the dunes, while bryophyte species richness was higher at the bottoms and decreased towards the tops of the dunes. Ground vegetation species richness and species’ horizontal and vertical structure on forested dunes were highly dependent on topography-induced differences, aspect, height and zone of the dunes. The most important factors controlling the complex of ground vegetation were light conditions, soil water content, thickness of the moderately decomposed litter layer and soil potassium and calcium content.

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Draft Genome Sequence of the Enteropathogenic Bacterium Campylobacter jejuni Strain cj255

Genome Announcements ◽

10.1128/genomea.01223-15 ◽

2015 ◽

Vol 3 (5) ◽

Cited By ~ 1

Author(s):

Fariha Masood Siddiqui ◽

Muhammad Ibrahim ◽

Nighat Noureen ◽

Zobia Noreen ◽

Richard W. Titball ◽

...

Keyword(s):

Global Health ◽

Host Range ◽

Campylobacter Jejuni ◽

Genome Sequence ◽

Draft Genome ◽

Epidemiological Studies ◽

Draft Genome Sequence ◽

Broad Host Range ◽

Bacterial Gastroenteritis

The enteropathogen Campylobacter jejuni is a global health disaster, being one of the leading causes of bacterial gastroenteritis. Here, we present the draft genome sequence of C. jejuni strain cj255, isolated from a chicken source in Islamabad, Pakistan. The draft genome sequence will aid in epidemiological studies and quarantine of this broad-host-range pathogen.

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Oil palm cultivation enhances soil pH , electrical conductivity, concentrations of exchangeable calcium, magnesium, and available sulfur and soil organic carbon content

Land Degradation and Development ◽

10.1002/ldr.3657 ◽

2020 ◽

Vol 31 (18) ◽

pp. 2789-2803

Author(s):

Sanjib K. Behera ◽

Arvind K. Shukla ◽

Kancherla Suresh ◽

Kamireddy Manorama ◽

Ravi K. Mathur ◽

...

Keyword(s):

Electrical Conductivity ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Content ◽

Soil Ph ◽

Oil Palm ◽

Organic Carbon Content ◽

Exchangeable Calcium ◽

Soil Organic Carbon Content ◽

Calcium Magnesium

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The roles of environmental variation and spatial distance in explaining diversity and biogeography of soil denitrifying communities in remote Tibetan wetlands

FEMS Microbiology Ecology ◽

10.1093/femsec/fiaa063 ◽

2020 ◽

Vol 96 (5) ◽

Cited By ~ 2

Author(s):

Xiaoliang Jiang ◽

Wenzhi Liu ◽

Lunguang Yao ◽

Guihua Liu ◽

Yuyi Yang

Keyword(s):

Electrical Conductivity ◽

Soil Moisture ◽

Soil Temperature ◽

Community Composition ◽

Environmental Filtering ◽

Operational Taxonomic Unit ◽

Amplicon Sequencing ◽

Spatial Distance ◽

Wetland Type ◽

Α Diversity

ABSTRACT The relative importance of local environments and dispersal limitation in shaping denitrifier community structure remains elusive. Here, we collected soils from 36 riverine, lacustrine and palustrine wetland sites on the remote Tibetan Plateau and characterized the soil denitrifier communities using high-throughput amplicon sequencing of the nirS and nirK genes. Results showed that the richness of nirS-type denitrifiers in riverine wetlands was significantly higher than that in lacustrine wetlands but not significantly different from that in palustrine wetlands. There was no clear distinction in nir community composition among the three kinds of wetlands. Irrespective of wetland type, the soil denitrification rate was positively related to the abundance, but not the α-diversity, of denitrifying communities. Soil moisture, carbon availability and soil temperature were the main determinants of diversity [operational taxonomic unit (OTU) number] and abundance of thenirS-type denitrifier community, while water total organic carbon, soil NO3– and soil moisture were important in controlling nirK-type denitrifier diversity and abundance. The nirS community composition was influenced by water electrical conductivity, soil temperature and water depth, while the nirK community composition was affected by soil electrical conductivity. Spatial distance explained more variation in the nirS community composition than in the nirK community composition. Our findings highlight the importance of both environmental filtering and spatial distance in explaining diversity and biogeography of soil nir communities in remote and relatively undisturbed wetlands.

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LIME AND GYPSUM APPLICATIONS ON SOIL CHEMICAL ATTRIBUTES AND INITIAL GROWTH OF EUCALYPTUS

FLORESTA ◽

10.5380/rf.v48i4.57455 ◽

2018 ◽

Vol 48 (4) ◽

pp. 573 ◽

Cited By ~ 1

Author(s):

Camila Adaime Gabriel ◽

Paulo Cezar Cassol ◽

Marcia Aparecida Simonete ◽

Letícia Moro ◽

Priscylla Pfleger ◽

...

Keyword(s):

Electrical Conductivity ◽

Soil Ph ◽

Soil Phosphorus ◽

Dry Weight ◽

Initial Growth ◽

Soil Electrical Conductivity ◽

Shoot Dry Weight ◽

Eucalyptus Dunnii ◽

Negative Effect ◽

Chemical Attributes

Eucalyptus crops in Southern Brazil are generally conducted in acidic soils, thus their yield can be increased by lime and gypsum applications. The objective of this study was to evaluate the effect of lime and gypsum applications on soil chemical attributes and initial growth of Eucalyptus benthamii and Eucalyptus dunnii in a Humic Cambisol (Inceptisol). The experiment was conducted in a greenhouse, with seedlings of both species of eucalyptus grown in soil treated with different rates of lime (0, 3, 6, and 12 Mg ha-1), and gypsum (0, 6, 3, 12.6, and 25.2 Mg ha-1). At 90 days after application of the treatments, the soil chemical attributes and growth components of eucalyptus seedlings. The lime increased the production shoot dry weight, however, the response to gypsum was negative. The lime increased the soil pH, exchangeable calcium (Ca), base saturation (V %), and slightly the soil electrical conductivity, decreased the soil aluminium saturation (m %), and promoted little reduction in the exchangeable potassium (K) and magnesium (Mg) contents. The gypsum didn't alter the soil pH, but decreased the m%, increased soil phosphorus (P) contents, and expressively increased the electrical conductivity, which may have had a negative effect on the eucalyptus growth. In conclusion, the addition of limestone decreases the soil acidity and benefits the growth of eucalyptus seedlings. However, the addition of gypsum has no expressive effects upon those variables, but it can decrease the growth of seedlings when the rates are excessive.

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Effect of Soil pH on Sclerotial Germination and Pathogenicity of Sclerotium rolfsii1

Peanut Science ◽

10.3146/i0095-3679-24-1-5 ◽

1997 ◽

Vol 24 (1) ◽

pp. 17-19 ◽

Cited By ~ 5

Author(s):

M-Y. Shim ◽

J. L. Starr

Keyword(s):

Soil Ph ◽

Sclerotium Rolfsii ◽

In Vitro Study ◽

Vitro Study ◽

Acidic Soil ◽

Alkaline Soil ◽

Sclerotial Germination ◽

Greenhouse Tests

Abstract The effect of soil pH on sclerotial germination and pathogenicity of two isolates of Sclerotium rolfsii on peanut was examined. Sclerotial germination for both isolates was greater (P ≤ 0.05) in acidic soil than at alkaline pHs. Similarly, percentage of peanut stems infected by S. rolfsii in greenhouse tests was greater at soil pH 5.6 than at alkaline soil pHs (P ≤ 0.05), but disease did develop at soil pH 8.7 and 9.8. In contrast to a previous in vitro study, these data confirm that sclerotia of S. rolfsii will germinate and initiate disease at soil pH > 7.0.

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