Morphological, pathogenic and molecular characterization of Phoma spp. isolated from onion field soils in Puerto Rico.

1969 ◽  
Vol 92 (1-2) ◽  
pp. 73-86 ◽  
Author(s):  
Ismael E. Badillo-Vargas ◽  
Lydia I. Rivera-Vargas ◽  
Juan Calle-Bellido
Keyword(s):  
Puerto Rico ◽  
Disease Incidence ◽  
Its Region ◽  
Restriction Enzymes ◽  
Molecular Characteristics ◽  
Base Pairs ◽  
Rdna Its ◽  
Field Soils ◽  
Rdna Its Region

Thirteen Phoma spp. isolates collected during a survey conducted in onion field soils in Santa Isabel, Puerto Rico, were examined on the basis of morphology, pathogenicity and molecular characteristics. Twelve isolates were identified as Phoma putaminum Speg. and one isolate as an atypical Phoma macrostoma var. incolorata (section Phyllostictoides).This is the first report of P. putaminum and P. macrostoma var. incolorata for Puerto Rico and the Caribbean. In vitro, Phoma putaminum isolates were pathogenic to onion cvs. Mercedes and Excalibur, resulting in necrosis of young bulbs and roots seven days after inoculation. Disease incidence caused by P. putaminum was higher in cultivar Mercedes, ranging from 75 to 100%, than in P. macrostoma var. incolorata (0 to 25%). No symptoms were observed on cultivar Excalibur inoculated with P. macrostoma var. incolorata or on control plants. In vitro inoculations of commercial onion bulbs and field inoculations of roots failed to reproduce symptoms, thus showing that P. putaminum and P. macrostoma var. incolorata are weak pathogens. Sequence size of the nuclear internal transcribed spacer (ITS) of ribosomal DNA (rDNA) gene ranged from 458 to 610 base pairs (bp) for P. putaminum and was 456 bp for P. macrostoma var. incolorata isolate. Analysis of rDNA ITS region by PCR-RFLP showed that restriction enzyme, Hindlll, among other restriction enzymes evaluated (Alul, EcoRI, Clal and Seal), differentiate between P. putaminum and P. macrostoma var. incolorata isolates.

scholarly journals New Anastomosis Groups, AG-T and AG-U, of Binucleate Rhizoctonia spp. Causing Root and Stem Rot of Cut-Flower and Miniature Roses

2005 ◽  
Vol 95 (7) ◽  
pp. 784-792 ◽  
Author(s):  
Mitsuro Hyakumachi ◽  
Achmadi Priyatmojo ◽  
Mayumi Kubota ◽  
Hirokazu Fukui
Keyword(s):  
Sequence Data ◽  
Its Region ◽  
Restriction Enzymes ◽  
Anastomosis Group ◽  
Stem Rot ◽  
Cut Flower ◽  
Binucleate Rhizoctonia ◽  
Rdna Its ◽  
Rdna Its Region ◽  
Hyphal Anastomosis

Root and stem rot of cut-flower roses (Rosa spp.) was observed in commercial glasshouse-grown roses in 10 prefectures of Japan from 1998 through 2001. Binucleate-like Rhizoctonia spp. were isolated mainly from the disease plants. In all, 670 isolates were divided into two types based on cultural appearance; 168 isolates of light brown to brown type and 502 isolates of whitish type. A hyphal anastomosis reaction using representative isolates from each type revealed that the light brown to brown type belonged to anastomosis group G (AG-G), whereas the whitish type (AG-CUT) failed to anastomose with tester strains of binucleate Rhizoctonia AG-A through AG-S. Neither isolates of AG-G nor AG-CUT anastomosed with tester strains of a previously reported unknown AG (AG-MIN) of binucleate Rhizoctonia spp. collected from miniature roses. In pathogenicity tests, randomly selected isolates of the three groups caused root and stem rot on cut-flower and miniature roses. To differentiate AG-CUT and AG-MIN from known AGs of binucleate Rhizoctonia spp., restriction fragment length polymorphism (RFLP) and sequence analyses of a ribosomal (r)DNA internal transcribed spacer (ITS) region were conducted. Among the eight restriction enzymes used, HaeIII produced DNA banding patterns for AG-CUT that differed from those of tester strains and AG-MIN. Additionally, restriction profiles of AG-MIN differed from those of all tester strains. AG-G isolates from cut-flower roses had the same RFLP pattern as the tester strains of AG-G. Based on the results of hyphal anastomosis and RFLP and sequence analysis of an rDNA-ITS region, we propose that AG-CUT be designated AG-T and AG-MIN be designated AG-U, two new AGs of binucleate Rhizoctonia spp. The phylogenetic tree based on the sequence data of the rDNA-ITS region showed that isolates of AG-MIN were in a distinct clade from other AGs, whereas isolates of AG-CUT were in the same clade as those of AG-A. More detailed phylogenetic analysis besides rDNA-ITS region might be necessary for AG classification of binucleate Rhizoctonia spp.

scholarly journals Effective Management of Cucumber Powdery Mildew with Essential Oils

Agriculture ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1177
Author(s):  
Yasser S. Mostafa ◽  
Mohamed Hashem ◽  
Ali M. Alshehri ◽  
Saad Alamri ◽  
Ebrahem M. Eid ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Essential Oils ◽  
Disease Incidence ◽  
Its Region ◽  
Dry Weight ◽  
Positive Control ◽  
Powdery Mildew Fungus ◽  
Membrane Injury ◽  
Cucumber Powdery Mildew

This research evaluated the efficacy of essential oils in the management of cucumber powdery mildew. Essential oils of lemongrass, lemon, thyme, peppermint, abundance blend, purification blend, and thieves blend were tested in vitro and under greenhouse conditions in two separate experiments. The effects of essential oils were tested against powdery mildew disease at concentrations of 1.0–2.5 mL/L, and the consequent impact of the oils on plant growth was evaluated. Powdery mildew fungus, Podosphaera xanthii, was identified using sequencing of the ITS region. The essential oils significantly reduced disease incidence up to 77.3% compared with the positive control (p < 0.5). Moreover, the essential oils increased the plant length (up to 187 cm), leaf area (up to 27.5 cm2), fresh weight (up to 123 g), dry weight (up to 22.5 g), number of flowers (16.3), and metabolite content compared with the positive control (p < 0.5). Cell membrane injury decreased significantly in the oil-treated pants (p < 0.5), indicating the protective effect of essential oils. This study recommends the application of essential oils in an appropriate dose (2.5 mL/L) to protect cucumber plants against powdery mildew. Overdose of the oils (more than 2.5 mL/L) should be avoided due to adverse effects.

scholarly journals PCR-RFLP ITS-based analysis of wine yeast autochthonous strains isolated from different grape cultivars in Taman subregion

2021 ◽  
Vol 285 ◽  
pp. 05020
Author(s):  
Elena Lobodina ◽  
Ivan Suprun ◽  
Natalya Ageeva ◽  
Ekaterina Al-Nakib
Keyword(s):  
Genetic Analysis ◽  
Restriction Analysis ◽  
Its Region ◽  
Wine Yeast ◽  
Product Size ◽  
Rdna Its ◽  
Hanseniaspora Uvarum ◽  
Pcr Rflp ◽  
Autochthonous Yeast ◽  
Rdna Its Region

The studies present the results of morphological, cultural and genetic analysis of the ITS1-ITS4 region of the autochthonous yeast strains genome by using the HaeIII restriction enzyme. On the red and white grapes varieties, based on the morphology of the cells, autochthonous strains belonging to the genus Saccharomyces prevail – 83.3%, what is confirmed by genetic analysis of rDNA ITS region. Restriction analysis showed that all strains of the genus Saccharomyces belong to the species Saccharomyces cerevisiae / S. paradoxus. The percentage of Saccharomyces isolated on the Pervenets Magaracha variety is 86.7%, Krasnostop Anapsky - 80%. The non-Saccharomyces yeast had a product size of 750 bp, presumably of the species Hanseniaspora uvarum.

scholarly journals Inhibitory Effect of Trichoderma asperellum Isolate against Ralstonia solanacearum Causing Brinjal Wilt

2021 ◽  
Vol 24 (2) ◽  
pp. 107-120
Author(s):  
SMN Islam ◽  
SS Siddique ◽  
MZH Chowdhury ◽  
NJ Mishu
Keyword(s):  
Ralstonia Solanacearum ◽  
Disease Incidence ◽  
Its Region ◽  
Inhibitory Effect ◽  
Dual Culture ◽  
Trichoderma Asperellum ◽  
In Planta ◽  
Quantitative Test ◽  
Trichoderma Isolate

A native Trichoderma isolate was collected from the agricultural soil of Gazipur. This isolate was identified as a Trichoderma asperellum through morphology and analysis of internal transcribed spacer (ITS) region of ribosomal RNA gene sequence and reconstruction of the phylogenetic tree. The antagonistic effects of the newly identified T. asperellum isolate were assessed against brinjal bacterial wilt caused by Ralstonia solanacearum both in vitro and in planta. Both qualitative and quantitative bioassays were conducted in vitro. For qualitative tests, dual culture and antibacterial activity were carried out, and pathogen growth was observed visually. The antagonism of T. asperellum cell free culture filtrate on the growth of R. solanacearum was conducted in a quantitative test. Successful antagonism was recorded after both in vitro qualitative tests. In addition, the lowest colony forming unit was recorded in 100% of CFC (2.4±0.51 ×103 cfu/ml) in quantitative test. The T. asperellum inoculated plant showed low disease incidence (13.33%) when seedlings were challenged with R. solanacearum in planta experiment. Disease incidence was 100% for seedlings when treated with only R. solanacearum. The results showed that the isolated and identified T. asperellum isolate suppressed R. solanacearum growth in vitro and protected the seedling from wilting in planta. Therefore, this isolate could be considered as a potential isolate. Ann. Bangladesh Agric. (2020) 24(2) : 107-120

scholarly journals Phylogenetic Analysis and Molecular Diversity of Capsicum Based on rDNA-ITS Region

Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 87
Author(s):  
Kumpei Shiragaki ◽  
Shuji Yokoi ◽  
Takahiro Tezuka
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Analysis ◽  
Wild Species ◽  
Morphological Characteristics ◽  
Its Region ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Rdna Its ◽  
Rdna Its Region ◽  
Genus Capsicum

The genus Capsicum is comprised of 5 domesticated and more than 30 wild species. The region of nuclear ribosomal DNA internal transcribed spacers (rDNA-ITS) has widely been used for species identification, but has rarely been used in Capsicum. In this study, the evaluation of genetic diversity and a phylogenetic analysis were conducted using rDNA-ITS of 28 Capsicum accessions, including five domesticated and two wild species. We surveyed six conventional keys of domesticated species and another five traits in Capsicum accessions. Specific morphological characteristics were found in C. annuum, C. baccatum, and C.pubescens. Three subclones of each accession were sequenced, and rDNA-ITS polymorphisms were detected in all accessions excluding C. annuum, suggesting that incomplete concerted evolution occurred in rDNA-ITS of Capsicum. The genetic diversity was evaluated using nucleotide polymorphism and diversity. C. annuum had the lowest genetic diversity of all species in this study. The phylogenetic tree formed a species-specific clade for C. annuum, C. baccatum, and C. pubescens. The C. chinense clade existed in the C. frutescens clade, implying that it was a cultivated variant of C. frutescens. C. chacoense likely belonged to the C. baccatum complex according to its morphologic and genetic features. This study indicated that the rDNA-ITS region can be used for simple identification of domesticated Capsicum species.

scholarly journals Molecular identification and artificial cultivation of a wild isolate of oyster mushroom in Albania

2016 ◽  
Vol 10 (1s) ◽  
pp. 35
Author(s):  
Jordan Merkuri ◽  
Stefania Mirela Mang ◽  
Ippolito Camele ◽  
Magdalena Cara ◽  
Gian Luigi Rana
Keyword(s):  
Its Region ◽  
Edible Mushroom ◽  
Biological Efficiency ◽  
Potato Dextrose Agar Medium ◽  
Wild Isolate ◽  
Rdna Its ◽  
Pure Cultures ◽  
Rdna Its Region ◽  
And Diffusion ◽  
Artificial Cultivation

Basidiomata of a wild mushroom macroscopically recognised as <em>Pleurotus ostreatus</em> were observed on an oak trunk in a mixed wood of northern Albania. Pure cultures of the fungus were then obtained on potato-dextrose-agar medium. Molecular analyses of genomic DNA of the fungus confirmed its identification. The rDNA ITS region nucleotide sequence of the studied <em>Pleurotacea</em> matched at 99% those of two <em>P. ostreatus</em> strains already present in NCBI GenBank database. The rDNA ITS nucelotide sequences of two pure cultures of the Albanian <em>P. ostreatus</em> were deposited in EMBL database under the accession numbers LN849458 and LN849459. One of the fungus isolates was subsequently cultivated under protected and semi-natural conditions. Productivity and biological efficiency of the Albanian <em>P. ostreatus</em> ranged from about 10% to 16% and from 33 to 53.33%, respectively. This seems to be the first report on the artificial cultivation of <em>P. ostreatus</em> in Albania and could have, in the next future, a high economic impact on development and diffusion of this important edible mushroom over the country.

scholarly journals Molecular Genetic Characterization of Olpidium virulentus Isolates Associated with Big-Vein Diseased Lettuce Plants

Plant Disease ◽  
2010 ◽  
Vol 94 (5) ◽  
pp. 563-569 ◽  
Author(s):  
L. D. Maccarone ◽  
M. J. Barbetti ◽  
K. Sivasithamparam ◽  
R. A. C. Jones
Keyword(s):  
Molecular Genetic ◽  
Leaf Tissue ◽  
Its Region ◽  
Metropolitan Region ◽  
Tissue Samples ◽  
Reverse Transcription Pcr ◽  
Rdna Its ◽  
Australian Continent ◽  
Rdna Its Region ◽  
Southwest Australia

Lettuce plants showing symptoms of lettuce big-vein disease were collected from fields in the Perth Metropolitan region of southwest Australia. When root extracts from each plant were tested by polymerase chain reaction (PCR) using primers specific to the rDNA internal transcribed spacer (ITS) region of Olpidium brassicae and O. virulentus, only O. virulentus was detected in each of them. The nucleotide sequences of the complete rDNA ITS regions of isolates from five of the root samples and 10 isolates of O. virulentus from Europe and Japan showed 97.9 to 100% identities. However, with the six O. brassicae isolates, their identities were only 76.9 to 79.4%. On phylogenetic analysis of the complete rDNA-ITS region sequences of the five Australian isolates and 10 others, the Australian isolates fitted within two clades of O. virulentus (I and II), and within clade I into two of its four subclades (Ia and Id). Japanese isolates had greatest sequence diversity fitting into both clades and into all of clade I subclades except Ib, while European isolates were restricted to subclades Ib and Id. When the partial rDNA-ITS region sequences of two additional southwest Australian isolates, four from Europe, and four from the Americas were included in the analyses, the Australian isolates were within O. virulentus subclades Ia and Id, the European isolates within subclade Ic, and the American isolates within subclades Ia and Ib. These findings suggest that there may have been at least three separate introductions of O. virulentus into the isolated Australian continent since plant cultivation was introduced following its colonization by Europeans. They also have implications regarding numbers of different introductions to other isolated regions. Lettuce big-vein associated virus and Mirafiori lettuce big-vein virus were both detected when symptomatic lettuce leaf tissue samples corresponding to the root samples from southwest Australia were tested using virus-specific primers in reverse transcription–PCR, so presence of both viruses was associated with O. virulentus occurrence.

scholarly journals Deep-level diagnostic value of the rDNA-ITS region

1996 ◽  
Vol 13 (9) ◽  
pp. 1276-1295 ◽  
Author(s):  
M. A. Hershkovitz ◽  
L. A. Lewis
Keyword(s):  
Deep Level ◽  
Its Region ◽  
Diagnostic Value ◽  
Rdna Its ◽  
Rdna Its Region
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