Maximum Number Of Spores Research Articles

Aeromonitoring of Alternaria spores in the air of Zaporizhzhia city

The aim of the study was to determine the patterns of changes in the concentration of mold spores of the genus Alternaria in the air of Zaporizhzhia city. Materials and methods. The object of the study was the dynamics of Alternaria spore concentration in the atmospheric air of Zaporizhzhia city. The study was carried out at the Department of Medical Biology, Parasitology and Genetics of Zaporizhzhia State Medical University. Samples were taken annually from March 1 to October 31 by volumetric method using a Hirst-type trap. The device is yearly certified by the state metrological service with certificates. The samples were analyzed using a light microscope at ×400 magnification using the method of vertical transects. The results of the research were processed by applying the Statistica® for Windows 13.0 licensed software package. Results. The seasonal dynamics of fungal spores of the genus Alternaria in the atmospheric air of Zaporizhzhia was analyzed over several years: from 2015 to 2020. The beginning, end and duration of sporulation, maximum values were determined. Conclusions. Analyzing the average daily (for six years) indicators of the spore number in the air of Zaporizhzhia city, it can be concluded that their distribution is normal throughout the year, which corresponds to the intensity of spore formation, depending on changes in meteorological conditions, that is, an almost equally symmetric range from the optimum, which falls on the beginning of June and is associated with an increase in precipitation in this region. Thus, an average of 17 256 spores/m3 were determined over six years. The maximum number of spores was 680 spores/m3 (6.07). The average day fell on July 25, σ = 37.1. In general, sporulation lasted 119 days. Peak concentrations were recorded in summer and autumn.

Penicillium roqueforti conidia induced by L-amino acids can germinate without detectable swelling.

Penicillium roqueforti is used for the production of blue-veined cheeses but is a spoilage fungus as well. It reproduces asexually by forming conidia. Germination of these spores can start the spoilage process of food. Germination is typically characterized by the processes of activation, swelling and germ tube formation. Here, we studied nutrient requirements for germination of P. roqueforti conidia. To this end, > 300 conidia per condition were monitored in time using an oCelloScope imager and an asymmetric model was used to describe the germination process. Spores were incubated for 72h in NaNO3, Na2HPO4/NaH2PO4, MgSO4 and KCl with 10mM glucose or 10mM of 1 out of the 20 proteogenic amino acids. In the case of glucose, the maximum number of spores (Pmax) that had formed germ tubes was 12.7%, while time needed to reach 0.5 Pmax (τ) was about 14h. Arginine and alanine were the most inducing amino acids with a Pmax of germ tube formation of 21% and 13%, respectively, and a τ of up to 33.5h. Contrary to the typical stages of germination of fungal conidia, data show that P. roqueforti conidia can start forming germ tubes without a detectable swelling stage.

The Annual Variation of Allergenic Cladosporium and Alternaria Spores in the Atmosphere of Büyükorhan (Bursa), Turkey; Effects of Meteorological Factors

Fungal spores are important bio-allergens frequently encountered in the atmosphere. Cladosporium Link and Alternaria Nees spores are generally recorded as dominant in many atmospheric fungal spore studies and have high allergic effects on susceptible individuals. The species belonging to these two genera may live as pathogens on the plants and cause low yield. This study was carried out between January 2012 to December 2013. Durham sampler, which is the device of the gravimetric method, was used in the research. A total of 10817 spores were recorded in the Büyükorhan (Bursa) atmosphere during the consecutive years. 4119 spores belonged to the first year and 6698 to the second year. The total numbers of Cladosporium spores were observed much higher than the total numbers of Alternaria spores in both years. This study aims to determine the variation of atmospheric spores in these two genera during the two years by comparing them with meteorological factors. For both spore types, the maximum spore numbers were found between the June-August term. Summer months revealed a risky period in terms of atmospheric fungal spore allergy for sensitive individuals.

Minimal nutrient requirements for induction of germination of Aspergillus niger conidia

Aspergillus niger reproduces asexually by forming conidia. Here, the minimal nutrient requirements were studied that activate germination of A. niger conidia. To this end, germination was monitored in time using an oCelloScope imager. Data was used as input in an asymmetric model to describe the process of swelling and germ tube formation. The maximum number of spores (Pmax) that were activated to swell and to form germ tubes was 32.54% and 20.51%, respectively, in minimal medium with 50 mM glucose. In contrast, Pmax of swelling and germ tube formation was <1% in water or 50 mM glucose. Combining 50 mM glucose with either NaNO3, KH2PO4, or MgSO4 increased Pmax of swelling and germination up to 15.25% and 5.4%, respectively, while combining glucose with two of these inorganic components further increased these Pmax values up to 25.85% and 10.99%. Next, 10 mM amino acid was combined with a phosphate buffer and MgSO4. High (e.g. proline), intermediate and low (e.g. cysteine) inducing amino acids were distinguished. Together, a combination of an inducing carbon source with either inorganic phosphate, inorganic nitrogen or magnesium sulphate is the minimum requirement for A. niger conidia to germinate.

Aerobiological studies with special reference to airborne basidiospores of Ganoderma Karst. at Pune, Maharashtra, India.

The basidiospores of Ganoderma were trapped in abundance during the aerobiological studies at Pune, during the year 2012. The sampling was conducted during the rainy months from 18th June to 10th September. Volumetric continuous Tilak Air sampler was used for sampling. Maximum number of spores was observed in the month of August (25760/m3 of air), followed by September (16548/m3 of air). The total spore number was 47460/m3 of air. The highest spore catch (3472/m3 of air) was recorded on 1st September. The relationship between the airborne concentration of Ganoderma spore count and meteorological factors are discussed in the paper. This information could be important for the sensitive individuals as Ganoderma spores are known to be allergic.

Precipitation as the most affecting factor on soil–plant environment conditions affects the mycorrhizal spore numbers in three different ecological zones in Turkey

ABSTRACTMycorrhizal symbiosis is the one of the most important relationship between microbiota and plants to sustain plant nutrition in relatively unfavourable conditions. Somehow this relation is threatened by time, therefore, definition of the factors effecting mycorrhizal symbiosis has become essential. The aim of this study was to determine the differences in specific mycorrhizal parameters such as sporulation and soil–plant environment conditions in three different regions of Turkey. During 1996−2002, 53 soil series were selected from natural and agricultural plant communities in three different agro-ecological zones of Turkey: Central Anatolia (CA), the Southeastern Anatolian (SA) project area and the Coast of Mediterranean (CM). The arbuscular mycorrhizal fungus (AMF), spore numbers and mycorrhizal root colonization were related to the annual average precipitation, soil characteristics and host plant identity.In the CM zone (average annual precipitation of 650 mm), soils found under natural vegetation contained a maximum value of 108 spores g−1, with bare soils containing a minimum number of 0.1 spores g−1. In the CA zone (330 mm annual average precipitation), the maximum number of spores in the soil samples was 46.5 spores g−1 with a minimum of 6.8 spores g−1 and in the SA soil samples (380 mm annual average precipitation), a maximum of 48.4 spores g−1 and a minimum of 14.2 spores g−1 were recorded. The overall mean number of mycorrhizal spores g−1 soil was 15.5 ± 14.4, 22.2 ± 8.6 and 27.9 ± 25.4 for the CA, SA and CM zones, respectively. Mean spore numbers differed in only two of the three zones, with the third zone being intermediate. Precipitation was the most affecting factor on the sporulation of AMF. Also host plant species and certain soil parameters, such as positive correlations with CaCO3 and N-min and a negative correlation with organic matter, have an influence on sporulation.The key finding is that the cropping system has a large impact on spore numbers/abundance. Seventeen standing crops as well as bare soil, fallow and natural areas were compared. There are a large number of factors which can affect mycorrhizal development; in the present work, it seems that soil and crop management, and environmental factors (such as precipitation) affect sporulation and root colonization. Covering land surface with mycorrhiza-dependent cover crop, irrigation and less soil till may increase indigenous mycorrhizal spores.

Morphological, Pathological and Genetic Diversities among Cephalosporium maydis Isolates

Morphological, pathological and possible genetic variations among forty two Cephalosporium maydis isolates, obtained from 13 Egyptian Governorates, were evaluated. Clear differences among C. maydis cultures grown on PDA+0.2% yeast extract (PDAY) were found with respect to their growth rate and sporulation. However, the majority of isolates grew at the normal growth rate (7 days after incubation at 27±2°C), showed whitish grey and white colour, had rhizoid margin and displayed intermediate growth density. In most isolates, the maximum number of spores was observed at the third day of incubation at 27±2°C, but no spores were produced after the sixth day of growth. Under greenhouse conditions, the virulence of C. maydis isolates against maize cv. Boushy revealed that, in general, all the tested isolates were pathogenic and differed in their aggressiveness. Some isolates showed the onset late wilt symptoms, 65 days after sowing, whereas symptoms started to appear, 75 and/or 95 days after sowing. However, isolate No. 9 from Gharbiya caused the highest infection, 95 days after sowing (93.3%); meanwhile isolate No. 48 from Wadi El-Natroon recorded the least infection (13.3%). A highly negative correlation was observed between infection percentages and each of plant height or dry weight of plants. Also, no correlation was observed between morphological and pathological characters of the tested isolates. Genetic variability among 14 C. maydis isolates was also carried out in the present study using RAPD-PCR technique. Different levels of genetic variability were recorded among the tested isolates and the reference ones, where they clustered into four phylogenetic lineages. Moreover, slight relationship between the lineage of isolates and any of their geographic origin and their virulence was observed. However, no correlation was noticed between the lineage and the morphological characters of the tested isolates.

Effect of Seasonal Variation on Mycorrhizal Fungi Associated with Medicinal Plants in Central Himalayan Region of India

This research paper assesses the effect of seasonal variation on mycorrhizal fungi. Based on the richness of medicinal plants in Himalayan region, this research work considered three medicinal plants i.e. Catharanthus roseus Linn., Ocimum spp. and Asparagus racemosus Willd. The study was conducted at five districts of Uttarakhand state of India viz. Pauri Garhwal, Haridwar, Dehradun, Udham Singh Nagar and Almora. To account for seasonal variations, soil and root samples were collected in months of Jan-Feb, May-June and Sep-Oct from year 2006 to 2008. Furthermore, the study was directed to collect information about the distribution of VAM fungi in the medicinal plants in relation to spore population. This research work evaluated and analyzed the effect of temperature, altitude and seasonal conditions. The undisturbed natural vegetations revealed maximum spore numbers followed by cultivated and non-cultivated regions. Similarly, root colonization by VAM fungi was observed at higher levels in natural vegetations and cultivated sites in comparison to non-cultivated lands. The monthly and seasonal temperature varied and had considerable effect on VAM fungal population. The data obtained in the present study undoubtedly indicate that the sea-sonal variation in VAM fungi is significant with few exceptions. VAM fungi in medicinal plants differ in the manner and extent with which root colonization rate occurs and also differ in their capacity to form propagules. Most of the study reveals that host plant had much more effect on spore population. Number of spores also varied with the growing season of the host plant. During the present study most of the sites showed a general increase in spore number from Sep-Oct to Jan-Feb.

Application of different downstream processing methods and their comparison for the large-scale preparation of Bacillus thuringiensis var. israelensis after fermentation for mosquito control

Bacillus thuringiensis var. israelensis, a gram positive, spore-forming bacillus, produces parasporal crystal protein during sporulation, which is toxic in the mosquito larvae gut. An efficient downstream processing method for separating the spore crystal complex (SCC) from the fermented broth of B. thuringiensis var. israelensis is required to achieve maximum mosquitocidal activity. The different downstream processing methods, viz., tangential flow ultra-filtration, continuous centrifugation and acid precipitation were compared for their efficiency in separating SCC from broth obtained from a pilot-scale fermentor (100 l capacity). Among the three downstream processing methods, tangential flow ultra-filtration yielded the maximum amount of biomass (53.3 g/l), maximum number of spores (2.30 × 10 18 CFU/ml) and highest level of larvicidal activity (LC 50 28 nl/ml) against Aedes aegypti Bora-Bora strain followed by continuous centrifugation and acid precipitation methods.

Time‐Dependent Sporulation, Conidial Size and Germ Tube Formation in Alternaria tenuissima (Kunze ex Pers.) Wiltshire on Different Media

Time‐dependent sporulation, conidial size and germ tube formation in Alternaria tenuissima (Kunze ex Pers.) Wiltshire on different media were studied. The results indicate that maximum number of first spore was formed on potato dextrose agar (PDA) and new leaf extract of pigeon pea followed by old leaf extract of pigeon pea and distilled water (DW). The sporulation was relatively poor on other media. The maximum number of spores in a chain were produced on PDA and albumen +0.9% sodium citrate. Only one spore was seen in DW. According to time‐dependent sporulation, the media were divided into three categories: on some media the first spore was formed in 18 h, in another group it took 30–36 h and in the third group the first conidium was formed after 40 h. Four germ tubes were commonly formed on most of the media. The largest conidia were observed on potato dextrose and the smallest ones were seen on DW.

Distribution of vesicular-arbuscular mycorrhizal fungi in the natural ecosystem

Natural occurrence of vesicular-arbuscular mycorrhizal (VAM) fungi in Haryana soils showed that VAM sporulation was more intensive in the rhizosphere of nonlegumes than of legumes. Maximum number of spores (342 spores per 50 g of soil) was observed in the rhizosphere of mustard, followed by chickpea, wheat, pearl millet and pigeonpea. Four VAM generaviz. Glomus, Gigaspora, Sclerocystis andAcaulospora, were present there. Soil pH, total soil P, available P, type of soil, soil moisture and cropping season all variables influenced the VA mycorrhizal population in the natural ecosystem. Numbers of VAM spores highly correlated with the presence of total soil P and soil pH indirectly affected the VAM population through the total soil P. The spore population was abundant in sandy soils as compared to loamy sands. Drier soils had higher number of VAM spores. In summer, the VAM population in soil was less as compared to winter season.

Mass inoculum production of vesicular-arbuscular (VA) mycorrhizae: I. Selection of host in the presence of Azospirillum brasilense

Summary Among the eight grasses, inoculated with Azospirillum brasilense and Glomus macrocarpum, Pennisetum spp. recorded for increased production of good biomass and spores. However, other grasses Stylosanthes guvanensis and Cenchrus spp. also produced maximum number of spores. In general, vesicles, arbuscules and number of spore formation were enhanced due to seed inoculation of A. brasilense in presence the of G. macrocarpum . In few grasses formation of vesicles (Cenchrus sp. and Pennisetum parviflorum) and arbuscules ( S. guvanensis and S. scarbaeoides ) were also triggered due to A. brasilense inoculation.

Spore discharge in the red algae Bostrychia tenella and Caloglossa leprieurii from the Godavari estuary, India

Bostrychia tenella (Vohl.) J. Ag. and Caloglossa leprieurii (Mont.) J. Ag., two examples of species important for human consumption from estuaries in Asia, were studied with respect to spore formation and release with a long-term view to their mass cultivation. Plants were collected between January and December 1987 from three different regions of the Gautami Godavari estuary, India. Both species behaved rather similarly. Tetrasporophytic plants were present throughout the year, whereas carposporophytic plants were found only in certain months. Shedding of tetraspores was observed throughout the year, but with seasonal difference in their output. Carpospores were liberated from October to May when the material was available. Maximum shedding of carpospores and tetraspores was observed in December and January and the minimum number of tetraspores in August and carpospores in May. The maximum number of spores was liberated, when plants were submerged at 20% salinity.

Ecological and seasonal study of VAM in plant species available as forage plants

Roots and rhizosphere soil from five Forage species were collected over a year in the north-west region of Murcia (Spain). Maximum spore numbers were observed in the summer, declined during autumn and reached the minimum in winter. Spore density increased during the following spring. The highest mycorrhizal infection was recorded in spring, decreased in summer, remained relatively constant in autumn and decreased in winter. The identified endophytes were: Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe, Glomus geosporum (Nicol. and Gerd.) Walker, Sclerocystis rubiformis Gerd. and Trappe and Scuyellospora sp.

Effect of manganese on alkaline phosphatase production in Bacillus sp. RK11

Bacillus sp. RKll, an alkalophilic isolate from soil, produces an extracellular alkaline phosphatase. In the absence of Mn2+ in a complex medium, no alkaline phosphatase production or sporulation by the organism was detected. No other divalent metal could be substituted for Mn2+ in enzyme production or in sporulation. Manganous sulphate (70μ mol) gave highest enzyme production although spore numbers continued to increase with manganous concentrations above this level. Maximum alkaline phosphatase production occurred when the metal was present at the time of inoculation but maximum spore numbers were detected when the metal was added 8–12h after inoculation. Inorganic pyrophosphatase was not associated with extracellular alkaline phosphatase, but it was detected intracellularly. Ninety-five percent of the alkaline phosphatase was detected extracellularly.

Geographical Distribution and Host-Parasite Relationships of Plistophora ovariae (Microsporida, Nosematidae) in Notemigonus crysoleucas

Plistophora ovariae undergoes schizogony and sporogony in developing ova of the golden shiner. Destruction of the ova greatly reduces fecundity and causes spawning failures. The incidence and intensity of infection is described in 49 commercial fish farms from 12 states. The parasite was found in fish from 45 of 49 sources and in a farm pond and creek from Oklahoma. Overall incidence of infection was 48% of 2759 fish. No significant difference was found in the incidence of disease from fish propagated by either intensive or extensive culture methods. There was a significant difference in incidence of infection with host age. Incidence increased from 30% in age class 0 to 75% in age class 4. Intensity of infection decreased with age and varied with season; it was greatest in May and June. Thus, the maximum number of spores and infected ova occurred during the spawning season of the host. Infected fish were generally larger and heavier than uninfected fish. Reduced egg production (partial parasitic castration) allowed nutrients and energy to be used for faster growth.