Soil aeration capacity,an index for soil structure,tested against yield and root development of apple trees at various soil treatments and drainage conditions

Summary Under Dutch climatic and drainage conditions soil aeration, particularly of loam and clay soils, is an important factor in crop production. It is determined by soil structure and ground water level. A soil aeration capacity has been developed to quantify soil structure. This SAC has been based on a schematic concept of aeration in proportion to the interface between water and air in the soil. Assuming certain capillary properties of soil pores, it can be derived from the pF curve as the wall area of air-filled pores at field capacity.Experiments carried out in apple orchards in the western and south-western part of the Netherlands and in Lake I jssel Polders revealed that SAC is a valuable parameter for soil aeration, soil structure and therefore gives sound relations with root development and yield of apple trees. It is found that SAC can be basic for quantifying classification of soil structure.     

A new species of peyronellaea from Indian soil

Summary A new species of genusPeyronellaea, P. indianensis sp. nov., has been described. Its isolation from the soil is the first record to science. It differs from previously recorded five species parasitizing various host plants. As it is isolated on a filter paper buried in the soil, it is a cellulose decomposing fungus     

A new species of Monosporium from Indian soil

Summary A new species ofMonosporium, M. bharatensis sp. nov. has been described in this paper. For the first time it has been isolated from Indian soil.     

Discoidals and Problematical Stones from Mississippian Sites in Minnesota

Abstract

There is no conclusive evidence that discoidals, chunkey stones or similar problematical stones were used exclusively or intermittently for games, ceremonials, food preparation or other village purposes, but the weight of evidence from eyewitness accounts suggests the dominance of game use. There are several eyewitness records of the game as olaved by the tribes of the Southeast and by some Siouan tribes of the plains and the Missouri Valley. Discoidals are found most frequently at late prehistoric Mississippian sites.

Recent Minnesota finds include: a single artifact with unusual features (Fig. 1), identified tentatively as a chunkey game piece, recovered by the author in 1976 from the Bryan site; a broken, more conventional game stone discovered at the neighboring site of Silvernale in 1975 (Harrison, 1978); a surface find at the Bartron site in 1978 by John Barnett; and an artifact, either a chunkey stone or a grinding stone, also found by John Barnett near the entrance of Belle Creek into the Cannon River. All of these sites are in the Red Wing area and these recent finds, together with other known discoidals from Goodhue County, link the Mississippian villages of the Red Wing area to the chunkey playing region further south.     

An impact of drainage system on soil water conditions at Lidzbark Warminski experimental site

The aim of this study is to evaluate the impact of a drainage system on soil water conditions in a loam soil compared to that in undrained clay loam soil under various topographic conditions. The soils are located on a sloping area at Lidzbark Warminski experimental site (Poland) with well surface water outflow conditions and used as a pasture. The loam soil was drained with ceramic drainage pipes with an average drain spacing of 14 m and an average drain depth of 0.9 m, while the clay loam soil profile was not drained. The research was conducted during the period from 1999 to 2005. Ground water level as well as soil moisture content were measured monthly for both soil profiles. Meteorological conditions (precipitation and data for calculation of reference evapotranspiration) were also recorded. The results obtained show that in the loam soil (drained site) water level is on average 42 cm higher compared to that in the clay loam soil (not drained site). In both soils the amplitude of the ground water level changes was relatively high and exceeds 300 cm. In the drained loam soil, the water level position exceeded the depth of the drainage system in very wet, wet and average years. Under wet meteorological conditions the increase in ground water levels in the clay loam soil was slower than in the loam soil.     

Conjugative plasmids in multi-resistant bacterial isolates from Indian soil

Aims:  Determination of heavy metal and antibiotic resistance and presence of conjugative plasmids in bacteria isolated from soil irrigated with wastewater.
Methods and Results:  Composite soil samples were collected from Ghaziabad, Uttar Pradesh, India. Forty different bacteria were selected from nutrient agar and characterized by morphological, cultural and biochemical tests. All the isolates were tested for their resistance to different heavy metals and antibiotics. The DNA derived from multiple metal and antibiotic-resistant bacterial isolates was PCR amplified and plasmid-specific sequences (IncP, IncN, IncW, IncQ and pMV158-type) were analysed by dot blot hybridization. All isolates gave PCR products with trfA2 and oriT primers of the IncP group. These PCR products also hybridized with the RP4-derived probes. However, the samples were negative for all the other investigated plasmids as proved by PCR and dot blots.
Conclusions:  The presence of conjugative/mobilizable IncP plasmids in the isolates indicates that these bacteria have gene-mobilizing capacity with implications for potential dissemination of introduced recombinant DNA.
Significance and Impact of the Study:  The detection of IncP plasmids in all the bacterial isolates is another proof for the prevalence of these plasmids. We propose that IncP plasmids are mainly responsible for the spread of multi-resistant bacteria in these soils.     

Vittatispora, a new melanosporaceous genus from Indian soil

Vittatispora coorgii gen. sp. nov., isolated from soil in India, is described and illustrated. The fungus has morphological characteristics of the genera Melanospora, Sphaerodes and Syspastospora. The most striking feature is the presence of a thick hyaline ridge along the vertical axis of the lemon-shaped ascospores wall. Perithecia also have a long neck composed of adhering hyphae, similar to that of Syspatospora. Phylogenetic studies on the 28S rDNA indicate it is closely related to Melanospora and Sphaerodes and belongs in the Ceratostomataceae. The new genus is based on the distinctive morphology and phylogenetic analyses. The fungus grew in culture only conjointly with a sterile fungus which a BLAST analysis suggested was close to Tetracladium marchalianum.     

The Mississippian Heartland and Its Plains Relationship*

Abstract

The Cahokia site near East St. Louis, Illinois, was a gateway on the northwestern frontier of the Mississippian heartland. Its exact relationship to other Middle Mississippi cultures and to cultures of the Plains and Upper Great Lakes ar ea is still not fully under stood. It is clear, nonetheless, that these relationships, when more completely known, will prove to be :inuch more complicated than any suggested in current literature.     

Amphibian Body Impressions from the Mississippian of Pennsylvania,USA

Temnocorpichnus isaacleai is a new ichnogenus and ichnospecies of temnospondyl amphibian body impression from the Mississippian (Visean) Mauch Chunk Formation of eastern Pennsylvania, United States. The shovel-shaped head, robust limbs, relatively short trunk and smooth integument diagnose the ichnotaxon and readily distinguish it from Hermundurichnus and Sauropleura, the only other named body impressions of Paleozoic tetrapods. Temnocorpichnus is a compound ichnogenus in which the footprint ichnogenus Batrachichnus is a behaviorally distinct component. The temnospondyl identity of Temnocorpichnus adds to the sparse and earliest records of temnspondyls, which are of Visean age. The smooth integument of the ichnogenus does not support the presence of ventral scales or armor in the earliest temnospondyls, but body proportions of the Mauch Chunk body impressions indicate a relatively terrestrial temnospondyl not matched by any taxon now known from bones. Three closely associated impressions of Temnocorpichnus on a single bedding plane suggest some sort of gregarious behavior in Mississippian temnospondyls and may support speculation that internal fertilization and associated courtship behavior evolved independently in one group of amphibians more than 300 million years ago.     

The ultrastructure and distribution of micropores in the various developmental forms of Eimeria brunetti

The structure and distribution of micropores in the various developmental stages of Eimeria brunetti was examined. Micropores were observed in all the endogenous forms with the exception of the microgamete. Oocysts from chicken faeces were also examined at various stages of sporulation and micropores were demonstrated in zygotes, sporoblasts, sporozoites, and the residual cytoplasmic masses. The number of micropores per organism appeared to be correlated with the surface area of the organisms irrespective of whether these were endogenous or sporulating forms. The increase in the number of micropores did not appear to be related to micropore activity because semmingly active micropores were observed only in the trophozoites, in the early multinucleate forms (early shizonts and microgamonts), and in the early macrogamonts. All these forms, however, possessed relatively few micropores. No active micropores were ever observed within the sporulating oocysts.     

The ultrastructure of Blastocystis galli from chickens

The ultrastructure stages of Blastocystis galli were studied in chicken's intestine and in laboratory cultures. There were found morphological structures: surface coat (cell from chickens' intestine showed a very thick surface coat); cell membrane--there were some small electron-opaque deepening pockets on the membrane; inner membrane; endoplasmic reticulum with attached ribosomes, which present in the cytoplasm; all cells contained numerous of small vacuoles and large glycogen inclusions in cytoplasm; mitochondria with tubular cristae; nucleus with granules condensed chromatin; central vacuole; Golgi complex was represented by number of plates grouped in a pite; the cyst-like forms were surrounded by multilayered wall.     

The porosity of soil aggregates from bulk soil and from soil adhering to roots

Summary Total porosity and pore-size distribution (p.s.d.) were determined in soil aggregates taken in plots planted with maize and treated with farmyard manure and three rates of compost. Soil aggregates were collected from the soil adherent to the maize roots (root soil aggregates) and from bulk soil (bulk soil aggregates). Mercury intrusion porosimetry was used to evaluate the total porosity and the p.s.d. Treatments did not affect the total porosity of the bulk soil aggregates. The same was observed for the root soil aggregates. However the total porosity of the root soil aggregates was always lower than that of the bulk soil aggregates. The loss of total porosity was found to be due to a decrease in the percentage of larger pores with respect to the total.