Phenotypic Variability of Ceratocystis paradoxa Isolated from North Western and Western Provinces of Sri Lanka and its Bio Control by Potential Bio-Control Agent; Trichoderma viride

Coconut (Cocos nucifera) is an important economic crop in Sri Lanka; one of the world's largest exporters of coir fiber and coir products. Ceratocystis paradoxa is a pathogen causing stem bleeding, leaf and fruit rot in variety of crop plants including coconut. Since C. paradoxa is associated with coconut trees, there is an opportunity for the pathogen exist in coir and coir products as well. According to the quarantine requirements, this pathogen has to be free in coir and coir products that are exported from Sri Lanka. During this study the pathogen was isolated from the samples of coir collected from different locations in North Western Province and Western Province of Sri Lanka. Colony morphology and spore morphology were compared among these isolates. Bio-control and the sensitivity of the isolates to the antagonist were evaluated against Trichoderma viride. According to the results the pathogen was present in all the samples collected from different locations of the coconut growing triangle. The isolated colonies grown on Potato Dextrose Agar (PDA) plates were white in early stage but became black, one or two days later. The growing colonies produced two asexual spores; the endoconidia and chlamydospores. Endoconidia are formed in the conidiophores making long chains. They are thin-walled cylindrical 9-12 µm x 4.8-7.2 µm in size, yet two isolated from North Western Province had a smaller width of 2.4 µm endoconidia. Chlamydospores are thick walled formed in short chains, dark color, and are mostly oval shaped, 9.6-16.8µm x 7.2-9.6µm in size, yet one isolated from North Western Province had a width of 4.8 µm. The chlamydospores are varied in morphology according to the geographical distribution of the pathogen. The variability of chlamydospore morphology predicts the genomic variability among the isolates. Biological control of C. paradoxa using T. viride was successful in all the isolates used in vitro studies. The experiments showed similar effects of T. viride on all C. paradoxa isolates as the biological control agent by killing the vegetative growth and losing the spore viability.

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Relationship Among NAGase Enzyme Activity, CMT Score and Somatic Cell Count in Milk of Crossbred Dairy Cows with Sub-Clinical Mastitis in North-Western Province of Sri Lanka

Tropical Agricultural Research ◽

10.4038/tar.v31i4.8418 ◽

2020 ◽

Vol 31 (4) ◽

pp. 26

Author(s):

R. Rahularaj ◽

R. M. C. Deshapriya ◽

R. M. S. B. K. Ranasinghe

Keyword(s):

Enzyme Activity ◽

Sri Lanka ◽

Dairy Cows ◽

Somatic Cell ◽

Cell Count ◽

Somatic Cell Count ◽

Clinical Mastitis ◽

Western Province ◽

North Western

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Prevalence and Molecular Characteristics of Vibrio spp. Isolated from Preharvest Shrimp of the North Western Province of Sri Lanka

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-115 ◽

2012 ◽

Vol 75 (10) ◽

pp. 1846-1850 ◽

Cited By ~ 15

Author(s):

MADURA SANJEEVANI GONSAL KORALAGE ◽

THOMAS ALTER ◽

DUANGPORN PICHPOL ◽

ECKHARD STRAUCH ◽

KARL-HANS ZESSIN ◽

...

Keyword(s):

Sri Lanka ◽

Penaeus Monodon ◽

Molecular Characteristics ◽

Pathogenic Potential ◽

Western Province ◽

The North ◽

Geographical Regions ◽

Seafood Products ◽

North Western ◽

Vibrio Spp

This study investigated the prevalence and molecular characteristics of Vibrio spp. in farmed shrimp (Penaeus monodon) in Sri Lanka. A total of 170 shrimp samples (100 g of whole shrimp each) taken from individual ponds from 54 farms were collected 1 week prior to harvest from the North Western Province of Sri Lanka. Overall, 98.1% of the farms and 95.1% of the ponds were positive for Vibrio spp. in shrimp; at the pond level, V. parahaemolyticus (91.2%) was most common, followed by V. alginolyticus (18.8%), V. cholerae non-O1/non-O139 (4.1%), and V. vulnificus (2.4%). Multiple Vibrio spp. were detected in 20.6% of the ponds. None of the V. parahaemolyticus isolates (n = 419) were positive for the virulence-associated tdh (thermostable direct hemolysin) and trh (TDH-related hemolysin) genes. V. cholerae was confirmed by the presence of ompW, and all isolates (n = 8) were negative for the cholera toxin (ctxA) gene. V. cholerae isolates were serogrouped by PCR and identified as V. cholerae non-O1/non-O139. All four V. vulnificus strains, isolated from different ponds of two geographical regions, showed pathogenic potential; they belonged to vcgC sequence type, type B 16S rRNA genotype and contained a pilF polymorphism associated with human pathogenicity. The results of this study revealed the ubiquitous nature of vibrios in farmed shrimp. To minimize the potential risk of Vibrio infections due to handling or consumption of raw or undercooked seafood products, good manufacturing practices as well as proper handling and processing should be addressed.

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Isolation, molecular characterization and phylogeny of Naegleria species in water bodies of North-Western Province, Sri Lanka

PLoS ONE ◽

10.1371/journal.pone.0248510 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0248510

Author(s):

Nuwan Gunarathna ◽

Anjalie Amarasinghe ◽

Sunil Wijesundara ◽

Devika Iddawela ◽

Susiji Wickramasinghe

Keyword(s):

Phylogenetic Analysis ◽

Sri Lanka ◽

Bayesian Analysis ◽

Molecular Characterization ◽

Its Region ◽

Water Bodies ◽

Internal Transcribed Spacer Region ◽

Western Province ◽

The North ◽

North Western

Background The inland freshwater bodies in the North-Western Province of Sri Lanka have ideal environmental conditions for the Naegleria species. Therefore, the presence and prevalence of Naegleria species in the water bodies of North-Western Province were determined by molecular characterization and phylogenetic analysis in this study. Methods A total of 104 water bodies were selected from Kurunegala and Puttalam districts in the North-Western Province of Sri Lanka. Mean turbidity, pH, and temperature were recorded in each water body from three selected site. Centrifuged samples were cultured on non-nutrient agar plates with Escherichia coli. Enflagellation test positive isolates were subjected to DNA extraction and polymerase chain reaction using genus and species-specific primers targeting the internal transcribed spacer region (ITS) and Mp2CL5 gene. Phylogenetic analysis was performed using Bayesian and maximum likelihood (ML) methods. Results The prevalence of Naegleria species and N. fowleri in the study area were 23.07% and 1.92%. The prevalence of Naegleria species and the physicochemical parameters of the water bodies showed no significant correlation. Bayesian analysis of the ITS region revealed the Naegleria Sri Lankan (SL) isolates 1, 3, and 4 in a single clade separated from the 2 and 5. Furthermore, Bayesian analysis identified isolates 2 and 5 in the same clade with Naegleria sp. samples and N. Philippinensis forming a sister clade. However, in the ML tree, all isolates were in the same clade with Naegleria sp. samples and N. Philippinensis. Conclusions The present study reports the first isolation of pathogenic N. fowleri from Sri Lanka. Based on Bayesian analysis, SL isolates 2 and 5 form a separate clade from 1, 3, and 4. However, in ML analysis, all isolates are grouped in one clade with Naegleria sp. samples and N. philippinensis. Further investigations are required to confirm these findings.

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COMMUNITY PARTICIPATION IN SOLID WASTE MANAGEMENT: THE CASE OF KURUNAGALA MUNICIPAL COUNCIL IN THE NORTH WESTERN PROVINCE OF SRI LANKA

Malaysian Journal of Science ◽

10.22452/mjs.vol35no2.1 ◽

2016 ◽

Vol 35 (2) ◽

pp. 63-72

Author(s):

Mallika Pinnawala

Keyword(s):

Sri Lanka ◽

Waste Management ◽

Solid Waste ◽

Community Participation ◽

Solid Waste Management ◽

Municipal Council ◽

Western Province ◽

The North ◽

North Western

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Impact of Office Design on Employees' Productivity; A Case Study of Banking Organizations of North Western Province in Sri Lanka

SSRN Electronic Journal ◽

10.2139/ssrn.2910255 ◽

2016 ◽

Cited By ~ 1

Author(s):

W.A.M. Hansika ◽

P.A.B.H. Amarathunga

Keyword(s):

Sri Lanka ◽

Office Design ◽

Western Province ◽

North Western

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ENHANCEMENT OF GROWTH OF ONION (ALLIUM CEPA L.) BY BIOLOGICAL CONTROL AGENT TRICHODERMA SPP

Acta Agronomica Hungarica ◽

10.1556/aagr.49.2001.4.11 ◽

2001 ◽

Vol 49 (4) ◽

pp. 393-395 ◽

Cited By ~ 1

Author(s):

E. PAYGHAMI ◽

S. MASSIHA ◽

B. AHARY ◽

M. VALIZADEH ◽

A. MOTALLEBI

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Trichoderma Viride ◽

Control Agent ◽

White Rot ◽

Trichoderma Spp ◽

Sclerotium Cepivorum ◽

Randomized Design ◽

Allium Cepa L ◽

Significant Difference

The effect of Trichoderma harzianum and Trichoderma viride (isolated from mycoflora in the rhizosphere of onion) in increasing the growth of onion was studied in a completely randomized design in pots with 12 replications under greenhouse conditions at 21°C with a 12-h light/dark cycle (fluorescent and incandescent lighting). The biological control of Sclerotium cepivorum Berk, the causal agent of white rot of onion, was also investigated in this experiment. The addition of Trichoderma spp. to autoclaved soil (inoculation of 2/3 of the top soil in the pots with 4% (v/v) inoculum of T. harzianum and T. viride) significantly increased the growth and fresh weight of the onion plants (P=1%). The biological control of S. cepivorum was achieved with T. harzianum and T. viride, but no significant difference was observed between the two species.

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