ITS rDNA Sequences Research Articles

Continuous monitoring and comparative genetic analysis of attached outbreak species of Ulva prolifera in the Southern Yellow Sea.

With years of green tide outbreaks in the Southern Yellow Sea (SYS) and climate change, early findings over multiple years suggest that the green tide may originate from various pathways. Previous studies have identified attached outbreak species of U. prolifera in the intertidal zone along the SYS coast. However, there has been limited research tracking and monitoring their succession processes or conducting comparative genetic analyses with floating U. prolifera in corresponding years. Therefore, this study continuously monitors the succession process of attached outbreak species of U. prolifera along the SYS coast, utilizing morphological and molecular biological methods to investigate their phylogenetic relationship with floating U. prolifera. The findings suggest that the distribution of the attached outbreak species of U. prolifera occurred in the intertidal zone along the coast of Rudong, Jiangsu Province from February to April 2023. However, subsequent surveys up to March 2024 did not observe their presence again. Apart from May and June 2023, other months consistently exhibited a long-term presence of various species of attached macroalgae, including Ulva flexuosa, Ulva meridionalis, and Ulva linza. The morphological characteristics of the attached outbreak species closely resemble those of the floating U. prolifera. Genetic diversity analysis using ITS and 5S rDNA sequences revealed that all attached outbreak species and floating U. prolifera in the same year belong to the same haplotype with high conservation and consistency in their ITS and 5S rDNA sequences. This study also identified natural shedding among the attached outbreak species, confirming their potential as supplementary sources contributing to Yellow Sea green tide outbreaks along the SYS coast.

Morphological and Molecular Characterization of Two Species of Ligophorus (Monogenea: Ancyrocephalidae) in Mullets from the Yucatán Peninsula, with Comments on the Geographical Distribution of L. mediterraneus

BackgroundLigophorus Euzet and Suriano, 1977 is a specious genus of ancyrocephalid monogeneans parasitizing mullets around the world, with most species distributed in the western Pacific and the Mediterranean Sea. Only nine out of the 62 species in the genus have been reported from the Americas, and from them, only two have been sequenced.MethodsWe analyzed two species of Mugil (L.) from Northern Yucatán Peninsula. Specimens of Ligophorus were sampled from the gills of their hosts. The morphology of the specimens was examined. In addition, 28S and ITS rDNA sequences were obtained and compared with previous sequences downloaded from GenBank.ResultsWe discovered two species of Ligophorus using morphological and molecular characters, L. mediterraneus, parasitizing the stripped mullet Mugil cephalus off the coast of Celestún, and L. yucatanensis, parasitizing the silver mullet M. curema in four coastal lagoons. Sequence data of the latter species are reported for the first time.ConclusionOur findings showed that two species of Ligophorus occur in mugilids of the Yucatán Peninsula. One represents a widely distributed marine species with records in the Mediterranean Sea and the Yucatán Peninsula, whereas the second one, L. yucatanensis, represents an endemic species restricted to coastal lagoons of the Yucatán Peninsula.

Gongronella fusoacuminata (Cunninghamellaceae, Mucorales), a new species from Taiwan

Rhizosphere fungi play crucial roles in plant health and soil ecology. We describe and illustrate Gongronella fusoacuminata, a new species isolated from the rhizosphere soil of pine and mallow in Taiwan. Phylogenetic analyses based on both ITS and LSU rDNA sequences, in conjunction with unique morphological characteristics, confirmed its distinct taxonomic classification within the genus. The phylogenetic analyses revealed that G. fusoacuminata possesses distinctive sequences, clearly differentiating it from other species within the genus. In addition, G. fusoacuminata is distinguished by its fusiform sporangiospores with acuminate apices and their relatively large size, clearly discerning it from other documented species.

Co-cultivation of Bacillus amyloliquefaciens and Trichoderma harzianum: Synergistic effects on plant growth and biocontrol of jasmine collar rot

Jasmine (Jasminum officinale) is a valuable and culturally significant flowering crop in India. Still, its cultivation is greatly impacted by collar rot disease, caused by Sclerotium rolfsii Sacc., resulting in yield losses of up to 50%. This study explores co-culture technology, utilizing Trichoderma harzianum TR(D)-4 and Bacillus amyloliquefaciens BC(M)-2, as an integrated single-product solution for the biological control of this pathogen. Field surveys conducted across major jasmine-growing districts in Tamil Nadu revealed a range of disease severity (20% - 52%) and incidence (29% - 64%). The collar rot pathogen, and biocontrol agents were isolated from surveyed locations and identified through morphological characteristics and molecular phylogenetic analysis based on ITS and 16S rDNA sequences. In vitro assays using dual-plate and paired-plate methods demonstrated that Bacillus amyloliquefaciens BC(M)-2 achieved inhibition rates of 71.34% and 78.27%, respectively, while Trichoderma harzianum TR(D)-4 exhibited inhibition rates of 86.27% and 75.43% against Sclerotium rolfsii SR(D)-5. Co-culturing these antagonistic strains synergistically improved antifungal effectiveness, achieving an 87% inhibition rate against S. rolfsii compared to their separate cultures. The synergistic interaction in co-culture promoted the production of novel compounds, including alpha-bisabolol (AB), bis(2-ethylhexyl) phthalate, and harziandione, which enhanced plant growth and inhibited S. rolfsii. Further planta studies confirmed that the co-culture significantly reduced disease incidence and enhanced plant growth in both pre-and post-inoculation strategies. This research highlights the potential of co-culturing T. harzianum TR(D)-4 and B. amyloliquefaciens BC(M)-2 as an effective and sustainable approach for managing collar rot disease in jasmine.

First report of leaf blight of Avena strigosa caused by Pyrenophora avenicola in Japan.

Black oat (Avena strigosa Schreb.) is used as a cereal crop, forage crop or green manure in temperate regions. In Japan, it is mainly cultivated in Hokkaido island and, because of the vigorous initial growth and ability to suppress the proliferation of plant pathogenic nematodes (Uesugi et al. 2018), its use is recently increasing. In November 2021, a leaf spot and blight disease was observed in the grass cultivated in Kitahiroshima city (N43°0, E141°31). At first, blackish brown spindle-shaped or elliptical lesions, about 3 to 5 × 1 to 2 mm were formed on leaves, and they expanded by forming yellowish-brown halos around them, eventually resulting in leaf blight later on (Fig.1), damaging 5-10 % of leaf area, varied by cultivar. The lesions were excised, surface-sterilized, and incubated on water agar under near-UV light. Three single-spore isolates of Pyrenophora-like fungus were obtained from the lesions and deposited at the NIAS Genebank, Japan (https://www.gene.affrc.go.jp/index_en.php) as MAFF511692, 511693 and 511694. The sequences of ribosomal RNA gene (rDNA) and its internal transcribed spacer (ITS), and the gpd sequences of the isolates were analyzed as described by Marin-Felix et al. 2019. The rDNA-ITS sequences (GenBank accession no. LC769170, LC769171 and LC769172) of the isolates matched with that of the ex-type strain of Pyrenophora avenicola (MK539972) isolated from Avena seed. The sequences of the gpd (accession no. LC795722, LC795723 and LC795724) matched well with that of the ex-type strain (MK540180). Conidiophores of the isolates were septate, straight or flexuous, pale brown to olivaceous brown, 81.4 to 125.7 × 4.2 to 6.5 (ave. 106.4×5.7µm, n=50) µm, with hyaline vegetative hyphae (Fig.2). Conidia were slightly verrucose, cylindrical to obclavate, pale brown to olivaceous brown, 42.2 to 78.5 × 9.0 to 13.3 µm (ave. 56.9 ×10.4µm, n =50) and 2 to 7 distoseptate. This description overlap with the original description of P. avenicolai (Marin-Felix et al. 2019) and the leaf spot pathogen of Avena sativa reported in China (Chen et al. 2022). The fungus was identified as P. avenicola on the basis of morphology and molecular phylogenetic analysis. To produce inoculum, the isolate MAFF511692 was grown on V8 juice agar at 25°C under near-UV light for 7 days. Five plants each of cv. 'Soil saver', 'New oats' of A. strigosa (Kaneko seeds co.) and 'New almighty' of A. sativa (Snow brand seed co.) were grown in a greenhouse for approximately 14 days and then inoculated by atomizing them with the conidial suspension (104 conidia/ml) at the five-leaf stage. Five plants of each cultivar sprayed with sterilized distilled water served as the control. Inoculated plants were covered with plastic bags for 24 h at 25°C. After 5 days, blackish brown elliptical lesions developed on the leaves of all inoculated plants of both cultivars of A. strigosa (Fig. 3) and A. sativa, implying broad pathogenicity of the fungus to species and cultivars of Avena plants. Halo was not observed, maybe due to fewer stress in the greenhouse environment. Controls remained asymptomatic. The produced lesions were incubated as described above and the reisolated fungus was identified as P. avenicola based on the morphology, confirming Koch's postulates. To our knowledge, this is the first report of leaf blight caused by P. avenicola on black oat in Japan.

Emergence of Nigrospora Leaf Blight as Major Biotic Stress in South Eastern Coastal Region of India

Background: Nigrospora is one of the diversified pathogens with wide host range. Endophytic nature of Nigrospora oryzae has been reported previously. Daily variations in the climate led to the emergence of virulent infections from previously expressed weak ones. Nigrospora oryzae infestation comes as a major biotic stress under this present investigation. Methods: A study was conducted to examine the variability of Nigrospora oryzae by collecting isolates from various locations in the south coastal region of Odisha. The level of virulence was assessed and analyzed between 2021 and 2023 to anticipate the emergence and progression of disease. The pathogen was identified using molecular techniques through ITS-r DNA sequencing method. Result: Disease incidence was observed as a critical blast-like appearance, but greater in size, distinguishing it from blast. In the experiment, incomplete filling of grains was highest in MTU-7029 (39.73 plant-1) followed by Niranjana and Gobindobhog; disease incidence was recorded to be highest in Niranjana (60.03%) followed by MTU-7029 and Barsha; and grain yield plant-1 was observed to be highly affected in Gobindobhog (14.58 g plant-1 followed by MTU-7029 and Niranjana. Molecular confirmation was established by ITS-rDNA sequencing, resulted sequence NO 9 (528 bp)- OP592217 and NO 15 (519 bp)- OP592218, exactly matches gene bank accession numbers- MH748173 (India) and ON514037 (India) of Nigrospora database, with 99% accuracy.

Comparison of rDNA-ITS Sequences, Vegetative Compatibility, Biological Characteristics, and Thifluzamide Sensitivity of Rhizoctonia solani AG-3 PT, TM, and TB Subgroup Isolates Collected from Potato and Tobacco in China.

Potato black scurf and tobacco target spot are significant agricultural diseases primarily caused by Rhizoctonia solani AG-3, which is further classified into PT (potato type), TM (tomato type), and TB (tobacco type) subgroups, with the naming of these subgroups originally indicating their respective infection hosts potato, tomato, and tobacco. This study determined the subgroup classification of 129 R. solani AG-3 isolates recovered from tobacco leaves exhibiting target spot disease in major tobacco-cultivating regions of China, as well as 80 R. solani AG-3 isolates obtained from potato stem cankers and tuber sclerotia in Liaoning, Jilin, and Heilongjiang provinces, and Inner Mongolia autonomous region of China. Sequence analysis of the internal transcribed spacer (ITS) regions revealed that all potato isolates belonged to the R. solani AG-3 PT subgroup, whereas the tobacco isolates were classified into TM and TB subgroups. Specifically, 51 strains from the northeast (Liaoning, Jilin, and Heilongjiang provinces) belonged to the TM subgroup, while the others belonged to the TB subgroup. Phylogenetic analysis indicated a closer relationship between AG-3 TM and AG-3 PT compared to AG-3 TB. Population genetic analysis highlighted distinct genetic variations among the subgroups, with the AG-3 TB subgroup isolates exhibiting fewer ITS1 variable sites and the AG-3 PT subgroup displaying a higher number of ITS2 variable sites. Furthermore, comparisons were made regarding macroscopic vegetative interactions, biological characteristics, pathogenicity to potato and tobacco, and susceptibility to thifluzamide among the three subgroups. The results indicated no macroscopic somatic interactions among the subgroups, with the highest frequency of somatic incompatibility observed within AG-3 PT, followed by AG-3 TM, and AG-3 TB. Additionally, the three subgroups differed in colony color, sclerotium morphology, production time, and distribution location on potato-dextrose-agar (PDA) medium, with AG-3 TM being the least likely to produce sclerotia. Regarding temperature, optimal growth conditions varied among the subgroups. Regarding pathogenicity, the AG-3 PT subgroup strains were more pathogenic on tobacco and potato stem bases compared to the AG-3 TB subgroup, whereas the AG-3 TB and TM subgroup strains were more pathogenic on leaves. Notably, AG-3 TM exhibited remarkable virulence towards both the stem base and leaves. The AG-3 PT subgroup strains exhibited the highest susceptibility to thifluzamide, with a susceptibility baseline of 0.037±0.013 mg·L-1, followed by the AG-3 TM subgroup strains with a baseline of 0.111±0.034 mg·L-1, and the AG-3 TB subgroup strains with a baseline of 0.137±0.035 mg·L-1. This study contributes to a deeper understanding of the biology and etiology of the three subgroups of R. solani AG-3, providing a valuable theoretical basis for the scientific control and management of tobacco target spot and potato black scurf diseases in China.

Taxonomic revision of the genus Sarcosphaera (Ascomycota: Pezizales) in Europe and North America revealed unexpected diversity

Sarcosphaera (Ascomycota: Pezizales) is a genus of rare spring fungi, currently encompassing a single species, S. coronaria, which is red-listed in many European countries. The genus is characterized by large bright-colored fruit-bodies and high arsenic content. This study investigates the genetic diversity across Europe and North America. Using integrated molecular techniques, including ITS and 28S rDNA sequencing, we aimed to resolve the taxonomic ambiguities and assess their arsenic hyperaccumulation capabilities, a rare trait among fungi. We identified the presence of two species in the Western Palearctic (S. coronaria, S. crassa) and at least 12 additional lineages in North America, indicating a more complex taxonomic structure than previously recognized. To consolidate the taxonomy and nomenclature of these fungi, we selected reference specimens for S. coronaria and S. crassa and discussed their morphological and ecological differences. Two genera, Caulocarpa (C. montana) and Hydnotryopsis (H. setchellii), a genus comprising hypogeous fungi, are newly placed in the genus Sarcosphaera. Sarcosphaera is thus another genus where the rapid evolution of hypogeous forms from their above-ground ancestors took place. Furthermore, two new Sarcosphaera species, S. columbiana and S. pacifica, are described from the Pacific Northwest. Investigation of arsenic content of Sarcosphaera species revealed that arsenic mass fractions in ascocarps vary significantly between species and even within species across different geographical locations. Our findings have important implications for the taxonomy and conservation of the S. coronaria species complex and also point to future directions for further research in the taxonomy, geomycology, and toxicology of this group of fungi.

Additions to the genus Kirschsteiniothelia (Dothideomycetes); Three novel species and a new host record, based on morphology and phylogeny.

During a survey of microfungi associated with forest plants, four specimens related to Kirschsteiniothelia were collected from decaying wood in Guizhou, Hainan and Yunnan Provinces, China. Kirschsteiniothelia species have sexual and asexual forms. They are commonly found as saprophytes on decaying wood and have been reported as disease-causing pathogens in humans as well. In this study, we introduce three novel Kirschsteiniothelia species (K.bulbosapicalis, K.dendryphioides and K.longirostrata) and describe a new host record for K.atra, based on morphology and multi-gene phylogenetic analyses of a concatenated ITS, LSU and SSU rDNA sequence data. These taxa produced a dendryphiopsis- or sporidesmium-like asexual morph and detailed descriptions and micromorphological illustrations are provided. Furthermore, we provide a checklist for the accepted Kirschsteiniothelia species, including detailed host information, habitat preferences, molecular data, existing morphological type, country of origin and corresponding references.

First Report of Alternaria alternata Causing Alternaria Leaf Spot of Black Nightshade in China.

Black nightshade (Solanum nigrum L.) belongs to Solanaceae family, which is distributed all over China and has become one of the malignant weeds in cotton field in Xinjiang (Zhang et al., 2020; Zhang et al., 2021). During July 2016 to August 2023, leaf spot was observed on black nightshade in Hami and Shihezi city, Xinjiang, China. The spots appeared as brown circular or irregular, with some small black dots surrounded with yellow halos. Twenty five black nightshade plants were collected from a cotton field (100 m2) for pathogen isolation in Shihezi, July 2023. Leaf samples (2×2 mm) from the boundary between diseased tissue and healthy tissue, sterilized in 70% ethanol for 45 s, dipped in 2% NaClO for 30 s, rinsed three times with sterile distilled water, placed on potato dextrose agar (PDA) after dried and cultivated at 25°C in the dark for 4 days. Twenty-five fungal isolates were obtained and purified by using the single-spore isolation method, and all isolates were found to be similar in morphology, appeared as dark brown and produced dark brown pigmentation on PDA. Conidiophores were black brown, 8 to 58 × 10 to 20 μm, with 1 to 5 transverse septa and 0 to 3 longitudinal septa, the results similar to those of Alternaria alternata isolated from buckwheat (Li et al., 2021). To confirm this identification, total genomic DNA of the isolates were extracted by CTAB method (Doyle et al., 1987). The internal transcribed spacer (rDNA-ITS), Alternaria major allergen gene (Alt α1) and glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH) of the A. alternata 26 were amplified using the primers ITS1/ITS4 (Glass et al., 1995), Altα1-F/Altα1-R (Li et al., 2024) and gpd-F/gpd-R (5'-CAACGGCTTCGGTCGCAT- TG-3' / 5'-GCCAAGCAGTTGGTTGTG-3'), respectively. The rDNA-ITS, Altα1 and GAPDH gene sequences were deposited in GenBank (KX904867, PP263361, PP263360), and showed 100% identity (rDNA-ITS: 572 out of 609 bp; Alt α1: 514 out of 516 bp; GAPDH: 619 out of 619 bp) to A. alternata (KU179665; MW522975; MK451977), respectively. The multi-gene phylogenetic tree showed that the representative isolate was grouped with A. alternata and identified as A. alternata. Black nightshade was used for pathogenicity assay. Fifteen plants at 3 to 4-leaf stage were selected and sprayed with the conidial suspension (1.0×106 spores/mL) of A. alternata 26 after wound the underside of leaves (2 mm length) with inoculating needle. Five plants were sprayed with sterilized water as control. After inoculation, placed the plants in a plastic box and covered with plastic wrap to keep 80% relative humidity for 3 days at 25℃ in the greenhouse, then removed the plastic box. Symptoms of leaf spots appeared within 12 - 15 days that were similar to the symptoms observed in the field, and the fungal pathogen that was re-isolated from symptomatic leaves was identical to original pathogen on the basis of morphological and molecular analysis to fulfill Koch's postulates. This experiment was repeated three times, and the disease incidence was above 80% after inoculation at each time. To our knowledge, this is the first report of A. alternata causing leaf spot of black nightshade in China. This report will help us to monitoring distribution of the disease and providing theoretical basis for disease prevention and control.

Distribution and environmental preferences of Saprolegnia and Leptolegnia (Oomycota) species in fish hatcheries in Hungary

We studied for the first time the abundance and species distribution of water molds (Oomycota, Saprolegniales) in fish hatcheries in Hungary, with a focus on Saprolegnia and Leptolegnia spp. A total of 182 water mold isolates were obtained from different developmental stages of fish (eggs, fry, and adults) and water samples collected during the spawning season of cyprinids and salmonids. Of the ten water mold species identified based on their ITS–rDNA sequences, S. parasitica, S. ferax, and S. australis were the most abundant. Statistical analyses of species proportions in relation to the sample source and host preference revealed that S. parasitica was significantly more abundant in the host than in water samples, whereas the opposite trend was observed for S. ferax and S. australis. In addition, our results confirmed previous findings that S. australis and S. ferax prefer warm water (+21–24 °C) and that S. parasitica has a wide temperature tolerance (+3–24 °C). The DNA sequence identity analysis showed that the species demarcation criterion for Saprolegnia spp. was approximately 98 % identity, based on ITS–rDNA sequences. Furthermore, our phylogenetic analyses suggest that taxonomic revision of Leptolegnia spp. is necessary.

Aspergillus capibaribensis (Eurotiales, Trichocomaceae), a new species in section Cremei

In this study we describe a new species of Aspergillus in section Cremei deposited in the URM culture collection (Micoteca URM Profa. Maria Auxiliadora Cavalcanti) of the Departamento de Micologia, Universidade Federal de Pernambuco (Recife, Pernambuco, Brazil). Another strain was obtained from samples taken from pollen pots inside nests of Melipona scutellaris (stingless bee). Morphological and phylogenetic evidence based on sequencing of ITS rDNA, BenA, CaM and rpb2 markers supported the description of taxonomic novelty. Aspergillus capibaribensis sp. nov. is morphologically similar and phylogenetically close to A. flaschentraegeri - the distinctive features are uniseriate and hyaline conidiophores, short and smooth conidia and smaller vesicles compared to the micromorphological structures of A. flaschentraegeri. This record also expanded the knowledge of species in Aspergillus section Cremei in a tropical country such as Brazil.

Discovery of adults of the gorgoderid trematode Cercaria duplicata with first morphological description, molecular identification and notes on host specificity

Rhopalocercous Cercaria duplicata von Baer, 1827 develops in an intermediate host, the unionid bivalve Anodonta anatina (L.), but its adult form has been unknown. We examined eight fish species occurring in the presence of a highly infested population of A. anatina in the Zesławice reservoir (S Poland). Gravid Phyllodistomum specimens were obtained from the ureters of ide, Leuciscus idus (L.) and common rudd, Scardinius erythrophthalmus (L.). One of the rudd specimens was doubly infected, a trematode was also found in the urinary bladder. In addition, a gravid Phyllodistomum specimen was found in the ureter of a tench Tinca tinca (L.), caught in Lake Ilmėdas (Lithuania). In order to clarify the phylogenetic position of larval and adult gorgoderids and to establish their life cycle, ITS2 and 28S rDNA sequences were analysed. The analysis showed that adult Phyllodistomum specimens located in the ureters are conspecific with C. duplicata. The trematode found in the urinary bladder of S. erythrophthalmus was P. folium (Olfers, 1816). It is suggested that adult stages of C. duplicata should be referred to as Phyllodistomum duplicatum n. comb. The intercaecal position of the uterus and the deeply-lobed ovary are the main features distinguishing it from other Phyllodistomum species. Host specificity and ecology are discussed.

Competitive antagonistic action of laccase between Trichoderma species and the newly identified wood pathogenic Ganoderma camelum.

Ganoderma, a well-known genus in the Ganodermataceae family, has caused the extinction of several tree species due to its pathogenicity. This study explored the pathogenic effect of a newly identified Ganoderma species on trees and its competitive efficiency against Trichoderma species. Ganoderma camelum sp. nov. is characterized by small sessile basidiomata and a velvety, soft, camel-brown pileus. Phylogenetic analysis and ITS rDNA sequences indicated that the species were Trichoderma and Ganoderma camelum. Both fungal species competed antagonistically by secreting laccase. The laccase activity of G. camelum, with a value of 8.3 ± 4.0 U/mL, demonstrated the highest competitive activity against Trichoderma species. The laccase produced by T. atroviride (2.62 U/mL) was most effective in countering the pathogenic action of the novel G. camelum. The molecular weights of laccase were determined using SDS-PAGE (62.0 kDa for G. camelum and 57.0 kDa for T. atroviride). Due to the white rot induced by this Ganoderma species in the host tree, G. camelum showed the highest percentage inhibition of radial growth (76.3%) compared to T. atroviride (28.7%). This study aimed to evaluate the competitive antagonistic activity of Ganoderma and Trichoderma on malt extract agar media in the context of white rot disease in the host tree. This study concluded that the laccase from G. camelum caused weight loss in rubber wood blocks through laccase action, indicating tissue injury in the host species. Therefore, it was also concluded that G. camelum was more effective in pathogenic action of the host and resisted the biological action of T. atroviride. In principal components analysis (PCA), all the species associated with laccase exhibited a very strong influence on the variability of the system. The PIRG rate (percentage inhibition of radial growth) was strongly and positively correlated with laccase activity.

Comprehensive analysis of microbiome biodiversity in popular date palm (Phoenix dactylifera L.) fruit varieties

Due to its nutritional value and health benefits, the date palm (Phoenix dactylifera L.) is an essential dietary food crop throughout Middle Eastern and African countries. Consumers are concerned about the possible microbial contamination of dates, especially since most dates arriving in local markets are unprocessed. The absence of processing increases the possibility of microbial contamination, which raises the probability of microbial contamination. This study aims to analyze and evaluate the variability of fungal and bacterial microbiota identified in the most popular date palm fruits in Saudi Arabia. The study assessed ten date variety fruits from the most popular date palm varieties for consumption in Saudi Arabia and analyzed the microbial count. Morphological and molecular characterization and comparison of nuclear ribosomal DNA internal transcribed spacer (ITS) sequences identified 78 fungi, including 36 distinct species across 15 fungal genera. Alternaria, Fusarium, Curvilaria, Aspergillus, and Penicillium were the most frequent genera among the ten fruit cultivars studied, according to ITS-rDNA sequence analysis. Furthermore, 36 bacterial isolates were obtained from ten date varieties studied, each with a unique colony morphology. These isolates were identified based on sequence alignment and comparison of their 16S rDNA internal spacer regions to those available in public databases. The results showed that the bacterial isolates included 15 species from five bacterial genera. The results suggested that Bacillus, Stenotrophomonas, and Brucella were the prevailing genera among the ten tested fruit varieties. Some bacterial genera, such as Brucella, Achromobacter, and Stenotrophomonas, are well-known potential human pathogens. Chaetomium globosum was also recognized as air pollution causing adverse health effects such as allergies and as the causal agent of human fungal infections among the tested date varieties; the Rashodiah type exhibited the highest fungal contamination, whereas the Sagai variety displayed the lowest fungal contamination. Conversely, the Sukkari, Barhi, and Mejdool varieties were the most contaminated with bacteria among the ten tested varieties, while the Khalas variety showed the least bacterial contamination. To the best of the authors' knowledge, this study provides the initial comprehensive account of the molecular and morphological identification of all fungal and bacterial genera associated with date palm (P. dactylifera) fruits.

Diversity and Community Structure of Endophytic Fungi Isolated from the Brown Seaweed Sargassum thunbergii in Coastal Regions of Korea

This study investigated the diversity of endophytic fungi isolated from the brown seaweed, Sargassum thunbergia, collected from six coastal regions in Korea: Gangneung, Pohang, Buan, Taean, Tongyeong and Yeosu. A total of 154 fungal strains were isolated using ITS rDNA sequence analysis, resulting in 84 species across 43 genera. Species diversity, assessed based on the Shannon index, was highest in Tongyeong (H′=3.273), followed by Pohang (H′=3.209), Buan (H′=2.691), Yeosu (H′=2.649), Gangneung (H′=2.342), and Taean (H′=2.025). Principal Coordinates Analysis (PCoA) revealed that water temperature and dissolved oxygen are the primary environmental factors influencing the regional variation in fungal community structure. This study underscores the significance of environmental conditions in shaping the diversity and community composition of endophytic fungi in S. thunbergii.

A contribution on first report of morphogenetic characterization of Anisakis typica parasitizing Indian sand whiting, Sillago sihama from Central west coast of India.

The search for hitherto undiscovered larvae of Anisakis sp. from marine habitat in the Indian sub-continent yielded A. typica (Dujardin) larvae hitherto unconfirmed. The present study is the maiden attempt to report 3rd stage larvae of A. typica from the reef-associated Sillago sihama in Arabian Sea off the coast of Goa, which has been identified recently as reef-populated area within the maritime boundary of India. The morphometry of 3rd stage larvae has been presented with a record of molecular characterization. In the context of current study, the natural prevalence of A. typica larvae in marine piscine hosts of Arabian Sea in India was 6.84 % and of co-occurring Rotundocollarette capoori (Yadav, Kapoor and Malhotra) in the same fish was 13.65 %. The roundworms were confirmed to be A. typica by application of the molecular and genetic characterization based on ITS1, ITS2 and 18S rDNA sequence analysis. The infestation of reef-associated fishes in this study by anisakid worms study provided an opportunity to explore mechanism of ecological associations of coral reefs with parasitization in future.

Isolation and Identification of Postharvest Rot Pathogens in Citrus × tangelo and Their Potential Inhibition with Acidic Electrolyzed Water.

This study focused on the identification of rot-causing fungi in Citrus × tangelo (tangelo) with a particular emphasis on investigating the inhibitory effects of acidic electrolyzed water on the identified pathogens. The dominant strains responsible for postharvest decay were isolated from infected tangelo fruits and characterized through morphological observation, molecular identification, and pathogenicity detection. Two strains were isolated from postharvest diseased tangelo fruits, cultured and morphologically characterized, and had their gene fragments amplified using primers ITS1 and ITS4. The results revealed the rDNA-ITS sequence of two dominant pathogens were 100% homologous with those of Penicillium citrinum and Aspergillus sydowii. These isolated fungi were confirmed to induce tangelo disease, and subsequent re-isolation validated their consistency with the inoculum. Antifungal tests demonstrated that acidic electrolyzed water (AEW) exhibited a potent inhibitory effect on P. citrinum and A. sydowii, with EC50 values of 85.4μg/mL and 60.12μg/mL, respectively. The inhibition zones of 150μg/mL AEW to 2 kinds of pathogenic fungi were over 75mm in diameter. Furthermore, treatment with AEW resulted in morphological changes such as bending and shrinking of the fungal hyphae surface. In addition, extracellular pH, conductivity, and absorbance at 260nm of the fungi hypha significantly increased post-treatment with AEW. Pathogenic morphology and IST sequencing analysis confirmed P. citrinum and A. sydowii as the primary pathogenic fungi, with their growth effectively inhibited by AEW.

Microbial communities in rural and urban homes and their relationship to surrounding land use, household characteristics, and asthma status

The relationships between the microbial communities that develop within homes and local outdoor features, household conditions and respiratory health outcomes are not well understood. In this study, high-throughput bacterial 16S and fungal ITS rDNA sequencing were coupled with a quantitative, GIS-based land use approach in a sample of 95 homes in adjacent urban and rural areas to investigate how local land use features surrounding homes relate to the home microbiome. Bacterial richness was higher in homes surrounded by less development while fungal richness was higher in homes surrounded by more development. Home mycobiomes in less developed areas were enriched with crop-associated taxa whereas in more developed areas human-associated bacterial taxa and wood decaying fungal taxa predominated. Not all vegetation had the same effect on the home microbiome and distinct differences were observed between bacterial and fungal communities, and the distance between home and vegetation. Crops and tree coverage were strongly related to indoor mycobiomes due to the abundance of crop-related taxa and wood decaying taxa, respectively. Regarding asthma, the microbiomes in homes with asthmatic children had greater bacterial diversity and lower fungal diversity compared to homes without asthmatic children. In addition, ‘protective’ taxa were enriched in non-asthmatic homes. The buffer-based approach used for quantitatively categorizing land use and development levels around homes identified specific outdoor environmental factors that affect the indoor microbiomes in urban and rural homes. The study also supports the growing body of scientific evidence that the indoor microbiome can affect health outcomes such as childhood asthma.

Prasiolopsis wulf-kochii (Prasiolales, Trebouxiophyceae), a New Species Occurring in Hairs of the Sloth Bradypus tridactylus.

The monotypic genus Prasiolopsis has been known for a long time, but is often overlooked because of difficulties in identification and the morphological variability between uniseriate filaments and cell packages forming pseudoparenchymatic thalli depending on age. We investigated a strain (SAG 84.81) originally denoted as Trichophilus welckeri, which was isolated from the hairs of the sloth Bradypus tridactylus, and compared it with other available strains of Prasiolopsis and of the sister genus Pseudomarvania. Our investigations clearly showed that this strain differed in morphology, especially of the chloroplast, from those originally described for Trichophilus. Phylogenetic analyses of the SSU and ITS rDNA sequences revealed that the strain SAG 84.81 is sister to several strains of P. ramosa within the Prasiola clade (Trebouxiophyceae). Using the ITS-2/CBC approach, we clearly demonstrated that this strain represented a new species of Prasiolopsis, which we proposed here as P. wulf-kochii. In addition, we evaluated the ITS-2/CBC approach by comparing it with the two species of Pseudomarvania. All investigated strains showed CBCs and HCBCs, which support their species delimitation. The sequencing data of Trichophilus welckeri available in GenBank were phylogenetically re-evaluated by including all representatives of the Ulotrichales (Ulvophyceae). Our analyses showed that these sequences formed their own lineage within this order.