Screening of recreational areas of rivers for potentially pathogenic free-living amoebae in the suburbs of Tehran, Iran

A survey was conducted to determine the presence of free-living amoebae (FLA), especially Acanthamoeba and Naegleria, in river recreation areas in Tehran Province, Iran. All rivers surveyed were associated with human activity, and two were also a source of municipal tap water. Fifty-five water samples from 10 major rivers were screened for FLA and identified by morphological characters, PCR amplification targeting specific genes for Acanthamoeba (DF3 region of Rns gene) and other FLA (ITS PCR), and homology analysis. The percentage of positive FLA isolates was 27.3%, of which 80% were Acanthamoeba, assigned to the T4 and T15 genotype, and 20% were Naegleria. Isolation of Acanthamoeba T4 genotype (91.7%) from recreation areas could be a health threat and a sanitary risk associated with human activity where young people and tourists congregate in summer. Posting of warning signs and education of high-risk individuals are important for disease prevention. To the best of our knowledge this is the first report of genotype T15 (clustered with A. jacobsi) identified in Iran and the first report of the distribution of FLA such as Naegleria (N. pagei, N. clarki and N. fultoni) in recreation areas in rivers of Tehran Province using molecular methods.

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First Report of Clubroot on Capsella bursa-pastoris Caused by Plasmodiophora brassicae in Sichuan Province of China

Plant Disease ◽

10.1094/pdis-04-13-0395-pdn ◽

2014 ◽

Vol 98 (5) ◽

pp. 687-687 ◽

Cited By ~ 2

Author(s):

L. Ren ◽

X. P. Fang ◽

C. C. Sun ◽

K. R. Chen ◽

F. Liu ◽

...

Keyword(s):

Plasmodiophora Brassicae ◽

Tap Water ◽

Disease Incidence ◽

Morphological Characteristics ◽

Pcr Amplification ◽

Sichuan Province ◽

Clubroot Disease ◽

Cruciferous Vegetable ◽

First Report ◽

Resting Spores

Shepherd's purse (Capsella bursa-pastoris (L.) Medicus) is an edible and wild medicinal plant widely distributed in China. This plant has been cultivated in Shanghai, China, since the end of the 19th century. Infection of C. bursa-pastoris by Plasmodiophora brassicae, the causal agent of clubroot disease on Brassica spp. has been reported in Korea (2), but is not known to occur in China. In February of 2011, stunted and wilted shepherd's purse (SP) plants were observed in a field planted to oilseed rapes (B. napus) in Sichuan Province of China. Symptomatic SP plants also exhibited root galls. Disease incidence was 6.2% and 100% for SP and B. napus, respectively. Root galls on diseased SP plants were collected for pathogen identification. Many resting spores were observed when the root galls were examined under a light microscope. The resting spores were circular in shape, measuring 2.0 to 3.1 μm in diameter (average 2.6 μm). PCR amplification was conducted to confirm the pathogen. DNA was extracted from root galls and healthy roots (control) of SP. Two primers, TC2F (5′-AAACAACGAGTCAGCTTGAATGCTAGTGTG-3′) and TC2R (5′-CTTTAGTTGTGTTTCGGCTAGGATGGTTCG-3′) were used to detect P. brassicae (1). No PCR amplifications were observed with the control DNA as template. A fragment of the expected size (approximately 520 bp) was obtained when DNA was amplified from diseased roots of SP. These results suggest that the pathogen in the galled roots of SP is P. brassicae. Pathogenicity of P. brassicae in SP was tested on plants of both SP and Chinese cabbage (CC) (B. campestris ssp. pekinensis). A resting spore suspension prepared from naturally infected SP roots was mixed with a sterilized soil in two plastic pots, resulting in a final concentration of 5 × 106 spores/g soil. Soil treated with the same volume of sterile water was used as a control. Seeds of SP and CC were pre-germinated on moist filter paper for 2 days (20°C) and seeded into the infested and control pots, one seed per pot for planted for CC and four seeds per pot for SP. The pots were placed in a chamber at 15 to 25°C under 12 h light and 12 h dark. Plants in each pot were uprooted after 4 weeks and the roots of each plant were washed under tap water and rated for clubroot disease. No disease symptoms were observed in the control treatments of SP or CC. Plants of both species showed symptoms of clubroot, with the disease incidence of 62.5% and 100% on SP and CC, respectively. The pathogen was isolated from diseased roots of each plant and confirmed as P. brassicae based on morphological characteristics and PCR detection. To our knowledge, this is the first report of clubroot disease on C. bursa-pastoris in Sichuan Province of China. This finding suggests that it may be necessary to manage C. bursa-pastoris in cruciferous vegetable (cabbage, turnip) and oilseed rape production fields. References: (1) T. Cao et al. Plant Dis. 91:80, 2007. (2) W. G. Kim et al. Microbiology 39:233, 2011.

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First Report of Passion Fruit Anthracnose Caused by Colletotrichum constrictum

Plant Disease ◽

10.1094/pdis-04-21-0754-pdn ◽

2021 ◽

Author(s):

Na Wang ◽

Fumei Chi ◽

Zhirui Ji ◽

Zongshan Zhou ◽

Junxiang Zhang

Keyword(s):

Sequence Data ◽

Control Strategies ◽

Pcr Amplification ◽

Morphological Characters ◽

Fungal Species ◽

Passion Fruit ◽

Effective Control ◽

First Report ◽

Sterile Needle ◽

Morphologic Data

Passion fruit (Passiflora edulis) is widely cultivated in tropic and subtropic regions. Because of its unique and intense flavour and high acidity, passion fruit juice concentrate is used in making delectable sauces, desserts, candy, ice cream, sherbet, or blending with other fruit juices. Anthracnose of passion fruit is favored by frequent rainfall and average temperatures above 27°C. In August 2018, anthracnose on passion fruit was observed in commercial plantings in Lincang, Yunnan, China (23.88 N, 100.08 E). Symptoms included lesions of oval to irregular shapes with brown to dark brown borders. Infection covered most of the fruit surface with pink-to-dark sporulation as reported by Tarnowski and Ploetz (2010). A conidial mass from an individual sorus observed on an infected fruit was isolated and cultured on potato dextrose agar (PDA) supplemented with 50 μg ml-1 of streptomycin. From a single microscopic field, two monospore isolates were dissected using a sterile needle, subcultured, and referred to as BXG-1 and BXG-2. Morphological characters including conidia colour, size, and shape were similar between the two isolates. Conidia were aseptate and cylindrical with apex and rounded base. Conidial length ranged from 12.3 to 16.1 µm (avg. 13.5) and width ranged from 5.5 to 6.2 µm (avg. 5.7). Morphologic data were consistent with Colletotrichum constrictum (Damm et al., 2012). To further confirm the fungal species, the ribosomal internal transcribed spacer (ITS), partial sequences of actin (ACT), chitin synthase (CHS-1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and β-tubulin 2 (TUB2) were amplified and sequenced. Primers and PCR amplification were described by Damm et al. (2012). The sequences were compared to type sequences in GenBank. The results showed the ITS (GenBank accession MW828148 and MW828149), ACT (MW855882 and MW855883), CHS-1 (MW855884 and MW855885), GAPDH (MW855886 and MW855887), and TUB2 (MW855888 and MW855889) sequences of the isolates BXG-1 and BXG-2 were 98% identical with sequence data from strain CBS:128504 of C. constrictum. A maximum likelihood tree was constructed using MEGA-X version 10.1.6 (Kumar et al., 2018) based on a combined dataset of the ITS, ACT, CHS-1, GAPDH, and TUB2 sequences of BXG-1 and BXG-2, and those of 18 Colletotrichum spp. previously deposited in GenBank (Damm et al., 2012). The phylogenetic analysis showed that BXG-1 and BXG-2 belong to the C. constrictum clade. Based on morphology and DNA sequencing, BXG-1 and BXG-2 were identified as C. constrictum. To verify pathogenicity, passion fruit were sprayed with a suspension of 1 × 105 conidia ml–1. Control fruit were sprayed with sterilized water. After inoculation, fruit were incubated in an Artificial Climate Box at 27°C and 80% RH. Necrotic symptoms appeared 8 days after inoculation and were similar to those observed on fruit form the field. The pathogen was reisolated from lesions thus fulfilling Koch’s postulates. C. constrictum has been reported to cause anthracnose of citrus from Australia (Wang et al., 2021) and mango from Italy (Ismail et al., 2015). To our knowledge, this is the first report of C. constrictum causing anthracnose on passion fruit worldwide, and these data will provide useful information for developing effective control strategies.

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First Report of Anthracnose Fruit Rot Caused by Colletotrichum acutatum on Strawberry in Korea

Plant Disease ◽

10.1094/pdis-92-8-1247c ◽

2008 ◽

Vol 92 (8) ◽

pp. 1247-1247 ◽

Cited By ~ 1

Author(s):

M. H. Nam ◽

T. I. Kim ◽

M. L. Gleason ◽

J. Y. Song ◽

H. G. Kim

Keyword(s):

Pcr Amplification ◽

Morphological Characters ◽

Fruit Rot ◽

Colletotrichum Acutatum ◽

Pathogenicity Test ◽

First Report ◽

Strawberry Anthracnose ◽

Dark Green ◽

Average Size ◽

Species Specific

Symptoms typical of anthracnose fruit rot; sunken, dark brown lesions on maturing fruits, were found in a commercial field of strawberry (Fragaria × ananassa) cv. Cal Giant in Yangyang County, Korea in May 2007. Masses of conidia were produced in acervuli in the center of lesions. The fungus was isolated on potato dextrose agar (PDA). Colonies grown on PDA were pale to mouse gray and became dark green to black in reverse. Conidia were formed in orange-to-salmon pink masses in the center of the culture. The average size of conidia on PDA was 15.2 × 4.6 μm, and they were hyaline, straight, cylindrical, with pointed ends, and aseptate (1). The fungus did not form an ascigerous stage in culture. Mycelial growth rate was 7.5 mm per day at 25°C on PDA. The identity of two isolates was confirmed as Colletotrichum acutatum J.H. Simmonds by PCR amplification using species-specific primers TBCA and TB5 (2), resulting in a characteristic 330-bp band on agarose gel. Morphological characters were in accordance with previous reports on C. acutatum. A pathogenicity test was conducted with five healthy plants of cvs. Cal Giant, Maehyang, Seolhyang, Kumhyang, Akihime, and Redpearl. After fruits and flowers were sprayed with a conidia suspension (105 conidia per ml), the plants were maintained at 10 to 25°C and 100% relative humidity in a greenhouse. As a control, five healthy plants were sprayed with sterile distilled water and incubated under the same conditions. Dark brown, water-soaked spots appeared on mature fruits of all cultivars after 5 days, and lesions on green fruits appeared on individual achenes. Flowers developed dark lesions, dried out, and died. No symptoms were found on the control plants. After the pathogen was reisolated from fruits and flowers lesions, the morphological characters developed in culture as described above. To our knowledge, this is the first report of C. acutatum causing strawberry anthracnose in Korea. References: (1) B. J. Smith and L. L. Black. Plant Dis. 74:69, 1990. (2) P. Talhinhas et al. Appl. Environ. Microbiol. 71:2987, 2005.

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First report of charcoal rot caused by Macrophomina phaseolina on potato tubers in Mauritius

Plant Disease ◽

10.1094/pdis-02-21-0258-pdn ◽

2021 ◽

Author(s):

Sandhya Devi Takooree ◽

Hudaa Neetoo ◽

Mala Ranghoo-Sanmukhiya ◽

Jacquie vander Waals ◽

Mira Vojvodić ◽

...

Keyword(s):

Sodium Hypochlorite ◽

Tap Water ◽

Solanum Tuberosum L ◽

Pcr Amplification ◽

Its Region ◽

Macrophomina Phaseolina ◽

Negative Control ◽

Potato Tubers ◽

Charcoal Rot ◽

First Report

Charcoal rot, caused by Macrophomina phaseolina, is an important disease in tropical and subtropical regions which affects a broad range of host plants, including potato (Solanum tuberosum L.). In this crop, charcoal rot can reduce the marketable quality of tubers (Arora 2012) and cause yield losses up to 88% (Somani 2007). During a survey of a potato field of ‘Spunta’ cultivar in Goodlands, Mauritius (20°02'28.2"S 57°39'30.4"E) approximately 10% of tubers with grey pigmentation around the lenticels and small water-soaked spots with white dots were observed. These symptoms later advanced to dark brown to black patches on the skin surface, all conforming to typical symptoms of charcoal rot (Arora and Khurana 2004). Fragments of infected and adjacent healthy tissue were cut, thoroughly washed with tap water, surface sterilized for 30 s with 1% sodium hypochlorite (25% bleach), placed on chloramphenicol-amended Potato Dextrose Agar (PDA), and incubated for 5 days in the dark at 25±2oC. From all the inoculated plates, only fast-growing, dark brown, grey to black Macrophomina-like colonies grew and several mono-sclerotial isolates were obtained with uniform morphological features. Following staining with cotton lactophenol dye using the clean slide technique, the isolate 449G-19/M exhibiting typical characteristics of M. phaseolina (Arora and Dhurwe 2019) and forming flattened, globose, black sclerotia with an average diameter of 180 µm (n= 50), was selected and used for further characterization. Identification was confirmed by sequencing of the ITS region of rDNA. Total DNA was extracted directly from the mycelium using a DNeasy Plant Mini Kit (Qiagen, Hilden, Germany), following the manufacturer’s instructions, while PCR amplification and sequencing were performed with primers ITS1-F (Gardes and Bruns 1993) and ITS-4 (White et al. 1990). The nucleotide sequence of the isolate 449G-19/M (Accession No. MW301138) shared 98.28 to 99.80% similarity with over 70 M. phaseolina isolates in GenBank (99.18% with isolate from Zea mays, Accession No. KF531825 (Phillips et al. 2013)). Pathogenicity was tested on 20 healthy tubers which were initially disinfected with 2% sodium hypochlorite for 1 min and individually placed in pots (20 cm ø) containing sterile substrate. Ten tubers were inoculated by placing colony fragments of 7-day-old cultures of the isolate 449G-19/M near each tuber. Similarly, 10 tubers inoculated with sterile PDA served as a negative control. The plants were maintained in greenhouse conditions, watered daily, and assessed for the presence of symptoms 8 weeks post emergence. All inoculated tubers exhibited charcoal rot on progeny tubers while control plants remained symptomless. Koch’s postulates were fulfilled successfully and the fungus recovered from the inoculated plants. Although M. phaseolina was previously observed in Mauritius on groundnut resulting in pre-emergence rot and collar rot (Anonymous 1962), to our knowledge, this is the first report demonstrating charcoal rot on potato tubers caused by M. phaseolina in Mauritius. As the sclerotia can remain in the soil for long periods of time (Arora and Khurana 2004) and with prevailing conditions of global warming, charcoal rot may be a threat for potatoes and other local crops (Somani et al. 2013). This study will sensitize agricultural extension officers on this new disease and calls for routine surveillance to safeguard this crop.

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First Report of Anthracnose Caused by Glomerella acutata on Chili Pepper in China

Plant Disease ◽

10.1094/pdis-10-10-0727 ◽

2011 ◽

Vol 95 (2) ◽

pp. 219-219 ◽

Cited By ~ 11

Author(s):

H. Xia ◽

X.-L. Wang ◽

H.-J. Zhu ◽

B.-D. Gao

Keyword(s):

Pcr Amplification ◽

Morphological Characters ◽

Chili Pepper ◽

Colletotrichum Acutatum ◽

First Report ◽

Blast Search ◽

Rdna Its ◽

Its Sequence Analysis ◽

Pcr Products ◽

Needle Prick

A new anthracnose disease on chili pepper (cayenne pepper cv. Hongxiu 2003, fruiting type pepper) was found in Zhijiang County, Hunan, China in 2009. The disease was observed only on the fruits. Lesions were generally elongated, on which dark acervuli were arranged concentrically. Later, cracking of older lesions was observed. With a microscope, fungal conidia were observed to be 15.8 × 4.1 μm, fusiform or oval with one end acute, and single celled with two to seven oil globules. No setae were found on the acervuli. Eight isolates (HNZJ001–HNZJ008) showed no difference in colony feature when cultured on potato dextrose agar. All the isolates showed white growth at the early stages, but colonies turned pink when they produced powdery spores and then finally became red gray. The average colony diameter was 68.5 to 72.3 mm after 7 days with obvious gray black concentric rings because of the development of aerial and substrate mycelia. After a needle-prick inoculation with a suspension of 1 × 106 spores per ml of HNZJ001 on 30 chili pepper fruits with three repeats, the same symptoms were observed and the same fungus was recovered. In bioassays, HNZJ001 caused lesions on both mature and immature fruits, while Glomerella cingulata strain LSQ1 (GenBank Accession No. HQ607386) used as a control did not infect immature fruits. PCR amplification was carried out by utilizing universal rDNA-ITS primer pair ITS4/ITS5. Sequencing of the PCR products of HNZJ001 (GenBank Accession No. GU059863) showed 100% identity to G. acutata (GenBank Accession No. EU008863) and Colletotrichum acutatum (GenBank Accession No. AF207794) after a BLAST search. The pathogen was identified as G. acutata (asexual stage: C. acutatum) on the basis of morphological characters and rDNA-ITS sequence analysis. Worldwide, it has been reported that pepper anthracnose might be caused by up to five species of Glomerella (Colletotrichum): G. cingulata, C. coccodes, C. capsici, C. dematium, and G. acutata (2), among which only the first three were previously reported in China. In recent years, G. acutata was reported on such plants as apple (3) and strawberry (1) in China, but not on pepper. To our knowledge, this is the first report of G. acutata on chili pepper in China. References: (1) X.-J. Ren et al. Acta Phytopathol. Sin. 38:325, 2008. (2) P. P. Than et al. Zhejiang Univ. Sci. B 9:764, 2008. (3) R. Zhang et al. Plant Dis. 92:1474, 2008.

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First Report of Simplicillium lanosoniveum Causing Brown Spot on Salvinia auriculata and S. molesta in Taiwan

Plant Disease ◽

10.1094/pdis-92-11-1589c ◽

2008 ◽

Vol 92 (11) ◽

pp. 1589-1589 ◽

Cited By ~ 12

Author(s):

R.-S. Chen ◽

C.-C. Huang ◽

J.-C. Li ◽

J.-G. Tsay

Keyword(s):

Tap Water ◽

Pcr Amplification ◽

Leaf Tissue ◽

Brown Spot ◽

Fluorescent Light ◽

Rrna Gene ◽

Sodium Hypochlorite Solution ◽

Sterile Water ◽

First Report ◽

Giant Salvinia

Salvinia spp. are small, floating ferns that grow in long chains of two oval leaves and a root-like third leaf. S. natans (L.) All., a native floating fern distributed in paddy fields, ponds, and ditches in Taiwan, has become critically endangered. Another two exotic species, S. auriculata Aublet (eared salvinia) and S. molesta Mitchell (giant salvinia), are sold in increasing frequency at local flower markets and aquarium shops and pose a serious threat when they find their way into the natural environment. Brown spot of S. auriculata was found in a home aquarium in December 2006 in Chiayi, Taiwan. Symptoms of the disease included many, irregular, dark brown spots on both upper and lower leaf surfaces. Lesions on the upper surface of the leaves were covered with white patches of mycelia and abundant conidia. Small pieces (approximately 2 × 2 mm) of diseased leaf tissue from the margin of individual lesions were surface disinfected in 1% sodium hypochlorite solution for 1 min, rinsed in sterile water, plated on water agar, and incubated at 25°C. Six isolates of the fungus were then isolated and transferred to potato dextrose agar (PDA). Isolate Cs0701 was identified morphologically as Simplicillium lanosoniveum (van Beyma) Zare & W. Gams on the basis of morphology of asexual reproduction structures and rDNA sequence analysis (1). In culture, this fungus formed whitish-to-whitish yellow, pulvinate colonies with matted surfaces. The reverse side of cultures was yellow to light brown. Small, ovate to spherical, hyaline conidia, 2.2 to 3.0 × 1.6 to 2.0 μm (average 2.4 × 1.9 μm) were formed. To confirm the identity of the fungus, PCR amplification and DNA sequencing of the internal transcribed spacer (ITS1-5.8S-ITS2 rRNA gene cluster) was conducted on isolates Cs0701 and Cs0702. The sequence of the PCR product was compared with sequences of closely related species listed in the GenBank database. Except for a single nucleotide, the ITS sequence of both isolates (480 bp; GenBank Accession No. EU939525) was identical to the rRNA of Simplicillium lanosoniveum (GenBank Accession No. AJ292396). Koch's postulates were performed to confirm the pathogenicity of the fungus on S. auriculata and S. molesta. After 14 days of growth on PDA, a spore suspension of isolate Cs0701 (106 spores per ml) was sprayed onto approximately 5 and 10 g of healthy S. auriculata and S. molesta plants, respectively, floated in 500-ml beakers filled with 300 ml of tap water. All treatments, including controls misted with sterile water, were replicated three times. The beakers were covered with plastic bags and placed in a growth chamber maintained at 25°C with 12-h fluorescent light cycles. After 2 days, the bags were removed. Symptoms developed on all inoculated plants 4 days after inoculation. In all cases, typical brown spots were observed. Simplicillium lanosoniveum was reisolated from all surface-disinfested infected tissues. Control plants developed no symptoms. Six isolates of the fungus are being maintained at the Department of Microbiology and Immunology, National Chiayi University, Taiwan. To our knowledge, this is the first report of Simplicillium lanosoniveum causing brown spot of S. auriculata and S. molesta in Taiwan. Reference: (1) R. Zare and W. Gams. Nova Hedwigia 73:1, 2001.

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First Report of Neofusicoccum parvum Associated with Chestnut Nut Rot in Italy

Plant Disease ◽

10.1094/pdis-01-21-0072-pdn ◽

2021 ◽

Author(s):

Salvatore Seddaiu ◽

Antonietta Mello ◽

Clizia Sechi ◽

Anna Cerboneschi ◽

Benedetto T. Linaldeddu

Keyword(s):

Elongation Factor ◽

Pcr Amplification ◽

Castanea Sativa ◽

Aerial Mycelium ◽

Mediterranean Area ◽

Morphological Characters ◽

Internal Transcribed Spacer Region ◽

Neofusicoccum Parvum ◽

First Report ◽

Sweet Chestnut

In autumn 2018, during a study on the pathogens involved in the etiology of chestnut nut rot symptoms observed in three of the main sweet chestnut (Castanea sativa) growing areas in Sardinia (Site 1: 39°56′55”N/09°11′45”E; site 2: 39°58’20”N/09°09′41”E; site 3: 40°52’50”N/09°08’45”E), Gnomoniopsis smithogilvyi was found to be the main causal agent. In addition to G. smithogilvyi, 15 out of 450 nuts processed, yielded on potato dextrose agar (PDA, 39 g/L) at 22°C white colonies with dense aerial mycelium becoming dark grey after 4 to 7 days. Pycnidia were produced within 4 weeks in half-strength PDA incubated at room temperature under natural daylight. The hyaline, ellipsoid to fusiform and aseptate conidia measured 13.4–19.2 × 4.8–7.7 μm (n = 50). All morphological characters matched those reported for Neofusicoccum parvum by Phillips et al. (2013). Identity of isolates was confirmed by DNA sequence analysis of the internal transcribed spacer region (ITS) and part of the translation elongation factor 1-alpha gene (tef1-α). DNA extraction, PCR ampliﬁcation reactions and DNA sequencing were carried out according to Linaldeddu et al. (2016). In the phylogenetic analysis based on combined ITS and tef1-α gene sequences the N. parvum isolates clustered within two well-supported subclades. In the first subclade (ML bootstrap = 88%) three isolates clustered together with the ex-type culture of N. parvum (CMW9081) while in the second subclade (ML bootstrap = 95%) three isolates clustered together with the ex-type culture of Neofusicoccum algeriense (CBS 137504), a species recently synonymised with N. parvum by Lopes et al. (2016). Sequences of six representative isolates were deposited in GenBank (MK968559–MK968564 and MT010339–MT010344 for ITS and tef1-α, respectively). The pathogenicity of six isolates, belonging to the two haplotypes, was undertaken by inoculating five asymptomatic nuts per isolate. After disinfecting the nut surface with 70% ethanol and removing a piece of shell (5 mm diameter) with a sterile cork borer, the nuts were inoculated with a same-sized agar-mycelium plug cut from the margin of a 5-day-old PDA colony. Ten control nuts were inoculated with a sterile PDA plug applied as described above. Inoculated nuts were kept in thermostat at 22 °C in the dark for 18 days. All nuts inoculated with N. parvum showed light-brown to dark necrosis of kernel associated with loss of tissue consistency. The symptoms were congruent with those observed in nature. All N. parvum isolates were successfully reisolated from all the inoculated nuts, fulfilling Koch’s postulates. No lesions were observed on controls. N. parvum is recognized as an emerging plant pathogen worldwide. In particular, several studies report N. parvum as a growing threat to agricultural and forest ecosystems in the Mediterranean area (Larignon et al., 2015; Manca et al., 2020). This is the first report of N. parvum causing chestnut nut rot in Italy.

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Free-Living Amoebae in Soil Samples from Santiago Island, Cape Verde

Microorganisms ◽

10.3390/microorganisms9071460 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1460

Author(s):

Djeniffer Sousa-Ramos ◽

María Reyes-Batlle ◽

Natália K. Bellini ◽

Rubén L. Rodríguez-Expósito ◽

José E. Piñero ◽

...

Keyword(s):

Pcr Amplification ◽

18S Rrna Gene ◽

Soil Samples ◽

Cape Verde ◽

Beach Sand ◽

Rrna Gene ◽

Pathogenic Microorganisms ◽

Free Living ◽

First Report ◽

Santiago Island

Free-Living Amoebae (FLA) are widely distributed protozoa, which contain some groups considered as pathogenic microorganisms. These members are able to produce several opportunistic diseases including epithelial disorders, such as keratitis and fatal encephalitis. Even though they have been reported in numerous sources, such as soils, dust and water, there is no legislation related to the presence of these protozoa in soil-related environments worldwide. Therefore, there are no established prevention or disinfection protocols to advise the population regarding FLA infections or eliminate these microorganisms from human-related environments to date. Acanthamoeba spp. are the most common FLA isolated in soil samples, which is also the most common genera found in clinical cases. Thus, the aim of the present study was to evaluate the presence of potentially pathogenic FLA in human-related soil samples of Santiago Island, Cabo Verde. A total of 26 soil samples were seeded in non-nutrient agar plates (2%), incubated at 26 °C, and monitored daily to evaluate the presence of FLA. DNA was extracted from those plates on which there was suspected FLA growth, and PCR amplification of the 18S rRNA gene was carried out. A total of 17 from the 26 analysed samples were positive for FLA, where Acanthamoeba is the most abundant isolated genus (14/17; 82,4%), with the T4 genotype being the most common (13/14; 92,9%), followed by the T5 genotype, A. lenticulata (1/14; 7,1%). Moreover, Vermamoeba vermiformis, Stenamoeba dejonckheerei and Vannella pentlandi were isolated in three other samples. To the best of our knowledge, this is the first report of FLA presence in Cape Verde and the first report of V. vermiformis in beach sand worldwide.

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New Findings on Scrophularia sect. Mimulopsis (Scrophulariaceae) from Iran

Novon A Journal for Botanical Nomenclature ◽

10.3417/2019271 ◽

2019 ◽

Vol 27 (4) ◽

pp. 238-247

Author(s):

Massoud Ranjbar ◽

Narges Rahchamani

Keyword(s):

New Species ◽

Pollen Morphology ◽

Conservation Status ◽

Morphological Characters ◽

Northern Iran ◽

Distribution Maps ◽

New Findings ◽

Tehran Province ◽

Micromorphological Characters ◽

A New Species

Scrophularia dianatnejadii Ranjbar & Rahchamani, a new species from Tehran Province in northern Iran, is described and illustrated. It is closely related to S. amplexicaulis Benth. and shares with it some diagnostic morphological characters such as habit, plant indument, phyllotaxy, and corolla shape and color. Both species are placed in Scrophularia L. sect. Mimulopsis Boiss. Macro- and micromorphological characters of the two are examined and compared. Pollen morphology of these species is investigated using SEM. Detailed descriptions, illustrations, distribution maps, and conservation status of both species are provided.

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UV ability to inactivate microorganisms combined with factors affecting radiation

Water Science & Technology ◽

10.2166/wst.1997.0718 ◽

1997 ◽

Vol 35 (11-12) ◽

pp. 107-112 ◽

Cited By ~ 7

Author(s):

A. M. Shaban ◽

G. E. El-Taweel ◽

G. H. Ali

Keyword(s):

Microbial Communities ◽

Uv Radiation ◽

Contact Time ◽

Tap Water ◽

Scenedesmus Obliquus ◽

Morphological Characters ◽

The Other ◽

Bacterial Cells ◽

Dark Repair ◽

Nile Water

In the present study, the effect of UV radiation on the inactivation of a range of microorganisms was studied. Each organism was seeded into sterile tap water and exposed to UV in batch experiments with changing turbidities. In addition, the effect of UV on microbial communities in river Nile water was examined. It was found that 1min contact time (0.5L/min flow rate) was effective against vegetative cells levels almost reaching zero (except with Staphylococcus aureus). On the other hand, spore-forming bacteria, Candida albicans and coliphage were more resistant to UV. This contact time caused coenobia cells in single form with Scenedesmus obliquus while for Microcystis aeruginosa colonies broke into smaller groups. Exposure of Nile water microbial communities to UV showed that yeasts and Aeromonas survived better than the other organisms while in the phytoplankton partial fragmentation occurred in some algal groups. The protective effect of turbidity differed between organisms, with increased contact time under conditions of stable turbidity having no effect on the organisms. At 20 NTU the UV radiation had no effect on the morphological characters of algal cells. In reactivation experiments, it is clear that photoreactivation, and not dark repair, takes place with bacterial cells. Only coliphage had no photoreactivation and dark repair responses although with coliphage and host, both reactivation processes worked well. Moreover, the irradiated algae regained their normal shape after 3 days in suitable media and enough light.

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