Dieback of cocoa (Theobroma cacao L.) plant tissues caused by the brown cocoa mirid Sahlbergella singularis Haglund (Hemiptera: Miridae) and associated pathogenic fungi

2015 ◽  
Vol 35 (04) ◽  
pp. 193-200 ◽  
Author(s):  
Joseph Chuks Anikwe ◽  
Henry Azuka Otuonye
Keyword(s):  
Secondary Infection ◽  
Insect Pest ◽  
Pathogenic Fungi ◽  
Plant Tissues ◽  
Strong Positive Correlation ◽  
Sahlbergella Singularis ◽  
Crop Husbandry ◽  
Black Pod ◽  
Opportunistic Pathogenic ◽  
Positive Correlation Coefficient

The brown cocoa mirid,Sahlbergella singularisis the most important insect pest of cocoa for field damage has been classified into three categories that include blast, stagheadedness and mirid pocket. The mirid attack predisposes the cocoa plant to secondary infection by opportunistic pathogenic fungi. This study evaluated the dieback conditions associated with mirid damage due to associated fungi from lesions on pods, twigs and pin punctures. The relationship betweenPhytophthorablack pod infection and mirid infestation in the field was also established. The results indicated that dieback progression from the mirid lesions (8.5 mm) was significantly different (P< 0.05) from that of pin punctures (7.8 mm).Lasiodiplodia theobromaehad the highest proportion of isolates from pods (33%), twigs (47%), and pin punctures (38%).Fusarium decemcellulare(Albonectria rigidiuscula) accounted for 27.8% and 31.6% from pods and twigs; however, it was not recovered from pin punctures. Other isolated pathogens wereAspergillusspecies andRhizoctoniaspecies. There was a significantly strong positive correlation coefficient of 0.74 between the mirid population and the black pod disease infection in the field. The major fruit-bearing season of cocoa witnessed an increase in mirid infestation and blackpod infection. The effect of mirid–pathogenic fungi-associated damage could be ameliorated through effective crop husbandry practices to ensure that cocoa plant tissues are not unduly exposed to biological and mechanical injuries.

Dynamics of fungal pathogens in host plant tissues

1995 ◽  
Vol 73 (S1) ◽  
pp. 1275-1283 ◽  
Author(s):  
Shigehito Takenaka
Keyword(s):  
Host Plant ◽  
Species Interactions ◽  
Fungal Biomass ◽  
Quantitative Methods ◽  
Plant Pathogens ◽  
Pathogenic Fungi ◽  
Molecular Methods ◽  
Plant Colonization ◽  
Fungal Colonization ◽  
Plant Tissues

To develop efficient control measures against fungal plant pathogens, the dynamics of host plant colonization during disease development and the interactions among fungi within host plant tissues need to be clarified. These studies require accurate quantitative estimation of specific fungal biomass in plant tissues. This has been approached by direct-microscopic methods, cultural methods, chemical determinations of fungal components, serological methods, and molecular methods. Among these methods, serological and molecular methods provide rapid, specific, and sensitive quantitative measures of fungal biomass in host plant tissues. Therefore, studies on fungal dynamics of host plant colonization using these two methods are presented. Some examples of species interactions among pathogenic fungi within host plants, such as synergism and competition, are reviewed and the usefulness of serological and molecular methods for studies on these interactions is presented. These quantitative methods will provide helpful information for understanding the ecology of plant pathogenic fungi, such as the dynamics of host plant colonization and species interactions. Key words: quantitative methods, fungal biomass, ELISA, PCR, fungal colonization, species interaction.

scholarly journals Management of Postharvest Diseases of Vegetables in a Tropical and Sub-tropical Environment of the Kingdom of Eswatini

2020 ◽  
pp. 1-13
Author(s):  
Diana M. Earnshaw ◽  
Michael T. Masarirambi ◽  
Bonginkhosi E. Dlamini ◽  
Kwanele A. Nxumalo
Keyword(s):  
Management Strategies ◽  
Pathogenic Fungi ◽  
Essential Amino Acids ◽  
Point Of View ◽  
Postharvest Diseases ◽  
Household Level ◽  
Post Harvest ◽  
Side Dish ◽  
Opportunistic Pathogenic ◽  
And Storage

Vegetables are important in human diets as a side dish eaten either cooked or raw as in salads. They are important for their nutritional contribution as major sources of minerals, vitamins, nine essential amino acids, beneficial phytochemicals, fibre and interesting colour from an aesthetic point of view. Despite the immerse health benefits offered by vegetables there are challenges encountered in their post-harvest handling and storage up to consumption. Challenges include post-harvest losses due to diseases. Some losses occur even at household level when vegetables are not stored appropriately when stored under the sink where humidity can be high leading to an environment which promotes diseases. Diseases in the post-harvest chain are caused by bacteria and opportunistic pathogenic fungi. Post-harvest losses of vegetables are not only a threat to nutritional security but a threat to food security as well. The aim of this research study was to document major post-harvest diseases of vegetables found in the Kingdom of Eswatini and to suggest appropriate management strategies or ways of alleviating them.

scholarly journals INCORPORATION OF UNCERTAINTY IN TECHNICAL AND ECONOMIC ANALYSIS OF A FELLER-BUNCHER

FLORESTA ◽  
2018 ◽  
Vol 48 (3) ◽  
pp. 403
Author(s):  
Danilo Simões ◽  
Ricardo Hideaki Miyajima ◽  
Rodrigo Petrongari Tonin ◽  
Paulo Torres Fenner ◽  
Gislaine Cristina Batistela
Keyword(s):  
Economic Analysis ◽  
Production Cost ◽  
Probability Distributions ◽  
Operating Cost ◽  
Timber Harvesting ◽  
Production Costs ◽  
P Value ◽  
Strong Positive Correlation ◽  
Technical And Economic Analysis ◽  
Positive Correlation Coefficient

The constant technical and economic analysis of timber harvesting operations is essential and determining, due to the monetary magnitude. Traditionally, these analyses are conducted deterministically, which does not allow obtaining values with probabilities of occurrence. Considering this issue, stochastic models were built in order to analyze the behavior of probabilistic production cost in felling operations with feller-buncher, through the Monte Carlo method. The study was conducted in the Central-West region of the state of São Paulo in a forest of Eucalyptus sp., with six years of age, planted in 3 x 2 m spacing. Technical analysis was based on the study of time and movements, which determined the effective productivity and economy in the hourly operating cost of the feller-buncher and in the production costs of the operation. Due to uncertainties, probability distributions were assigned to these results, which identified the most relevant variables and quantified the probabilities of the production cost. The results demonstrated that the fuel cost had a statistically significant strong positive correlation coefficient ( = 0.91) (p-value < 0.01). The hourly cost, consequently, was directly proportional to the production cost of the operation. The production cost of the operation in flat relief was 18% lower than the production cost of the operation in undulating relief.

scholarly journals In vitro interactions between primycin and different statins in their effects against some clinically important fungi

2010 ◽  
Vol 59 (2) ◽  
pp. 200-205 ◽  
Author(s):  
Ildikó Nyilasi ◽  
Sándor Kocsubé ◽  
Miklós Pesti ◽  
Gyöngyi Lukács ◽  
Tamás Papp ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Rhizopus Oryzae ◽  
Fungal Growth ◽  
Pathogenic Fungi ◽  
Titration Method ◽  
Antifungal Activities ◽  
Opportunistic Pathogenic ◽  
The Given ◽  
In Vitro Interactions

The in vitro antifungal activities of primycin (PN) and various statins against some opportunistic pathogenic fungi were investigated. PN completely inhibited the growth of Candida albicans (MIC 64 μg ml−1) and Candida glabrata (MIC 32 μg ml−1), and was very effective against Paecilomyces variotii (MIC 2 μg ml−1), but had little effect on Aspergillus fumigatus, Aspergillus flavus or Rhizopus oryzae (MICs >64 μg ml−1). The fungi exhibited different degrees of sensitivity to the statins; fluvastatin (FLV) and simvastatin (SIM) exerted potent antifungal activities against a wide variety of clinically important fungal pathogens. Atorvastatin, rosuvastatin and lovastatin (LOV) had a slight effect against all fungal isolates tested, whereas pravastatin was completely ineffective. The in vitro interactions between PN and the different statins were investigated using a standard chequerboard titration method. When PN was combined with FLV, LOV or SIM, both synergistic and additive effects were observed. The extent of inhibition was higher when these compounds were applied together, and the concentrations of PN and the given statin needed to block fungal growth completely could be decreased by several dilution steps. Similar interactions were observed when the variability of the within-species sensitivities was investigated.

scholarly journals Stream Sediments Geochemical Exploration in Wadi El Reddah area, Northeastern Desert, Egypt

2020 ◽  
Vol 10 (8) ◽  
pp. 809
Author(s):  
Hamed Ibrahim Mira ◽  
Hussein Kamal Hussein ◽  
Sameh Zakaria Tawfik ◽  
Neveen Salah Abed
Keyword(s):  
Correlation Coefficient ◽  
Sedimentary Rocks ◽  
Alkali Feldspar ◽  
Rare Metal ◽  
Stream Sediments ◽  
Strong Positive Correlation ◽  
Geochemical Exploration ◽  
Metal Contents ◽  
Positive Correlation Coefficient ◽  
The Relationship

<p>Wadi El Reddah representing a semi-closed basin, extends in the N-S direction. It has only one outlet at the northern tip while the wadi collects floodwater from internal tributaries along wall rocks. The present study discusses the relationship between geology and geochemistry data to detect anomalous radioactive locations. The geochemical maps show the mineralization areas with abnormal rare metal contents. This led to two uranium occurrences (GXXIII and GXXIV) at Gabal Gattar in the perthitic leucogranite. At Wadi El Reddah, high contents of pathfinder elements (REE, Y, Zn, Nb and As) were discovered at the southern and eastern boundaries. This may be attributed to the presence of alkali feldspar granite at Gabal Gattar at the upstream of Wadi El Reddah and also to the sharp contact between Gabal Gattar and Hammamat Sedimentary rocks. A strong positive correlation coefficient between Fe<sub>2</sub>O<sup>t</sup> and or Al<sub>2</sub>O<sub>3</sub> with Zr, Hf, Nb, Ta, REE, U, Rb, and Th reflects their association with thematization processes.</p>

scholarly journals An Investigation on the Harmful Biological Factors of Workplace among Administrative Workers of Power Plant in South of Iran

2018 ◽  
Author(s):  
Behnoush JAFARI ◽  
Bahram KOUHNAVARD ◽  
Mohammadreza NAJIMI ◽  
Fereshteh JAHANI ◽  
Zeinab MOSAVIAN ASL
Keyword(s):  
Power Plant ◽  
Personal Protective Equipment ◽  
Positive Culture ◽  
Pathogenic Fungi ◽  
Cross Sectional Study ◽  
Personal Hygiene ◽  
Protective Equipment ◽  
Biological Factors ◽  
Cross Sectional ◽  
Opportunistic Pathogenic

Introduction: The working conditions, type of activity, and production or consumption of different materials expose the employees to harmful biological factors, which leads to infectious diseases. The purpose of this study was to investigate the harmful biological agents of the work environment among administrative personnel of a power plant in south of Iran. Methods: This descriptive and cross-sectional study was conducted among 200 administrative workers of different sections of power plant in 2016. The participants used personal protective equipment and samples were collected from five parts of the participants' body including auricle, inside the ear, the area between the toes, palm of foot, toe nails. Finally, 1000 samples were collected. Results: The mean age of the workers was  years and all participants were male. Of the 1000 samples cultivated in the laboratory, 192 (96%) people had negative and 8 (4%) had positive culture results. The results showed that auricle had the highest rate of opportunistic pathogenic fungi (87.5%). The most positive cases of opportunistic pathogens were associated with workshops, warehouses, and operational buildings. Conclusion: Regarding the results of the study, we need to implement more health care in the mentioned places, observe personal hygiene in keeping the feet dry, not using protective handsets (air plug and earmuff) of other people, disinfecting the personal protective equipment, and daily washing to prevent the spread of the disease to other people.

Acceptability, attitude, and satisfaction of online learning among nursing students during COVID-19 lockdown: a cross sectional study

2013 ◽  
Author(s):  
Rini Maurya ◽  
Swarna Buddha Nayok ◽  
Sathyanarayana MT ◽  
Dhanashree Akshatha H.S.
Keyword(s):  
Online Learning ◽  
Nursing Students ◽  
Social Presence ◽  
Cross Sectional Study ◽  
Strong Positive Correlation ◽  
Sectional Study ◽  
Satisfaction Scale ◽  
Cross Sectional ◽  
The Mean ◽  
Positive Correlation Coefficient

Introduction: Due to the current Novel Corona Virus (COVID-19) pandemic related lockdown in India, regular classes are suspended to maintain social distancing. Educational institutions are now opting for online learning to facilitate and continue with the academic schedule of students. Aim: To evaluate the acceptability, attitude, and satisfaction of online learning among nursing students during COVID-19 lockdown. Settings and design: A cross-sectional study was conducted with 193 nursing students of a nursing college attached to private medical college and hospital, through online Google Forms questionnaires. Materials: Semi-structured proforma for socio-demographic details, Social Presence Scale (SPS), and related Satisfaction Scale (SS) were used for evaluation. Statistical analysis: Sociodemographic details were mainly descriptive and categories compared using Pearson’s correlation test and ordinal variables using Spearman’s Rho correlation. Results: The mean age of 20.01 years (Standard Deviation (SD) = 1.42), the mean score of SPS was 44.75 (SD=5.89) and that of SS was 31.12 (SD=7.59). SPS and SS scores correlated significantly (P<.000), with a strong positive correlation coefficient of .602. Positive attitude towards online learning was found in 61.7% of students, and 62.7% opined their experience to be satisfactory. Conclusion: This study shows that nursing students show adequate acceptability, positive attitudes, and higher satisfaction levels related to online learning, as determined by Social Presence Theory, during COVID-19 lockdown in India.

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