International Letters of Natural Sciences Vol. 46

Abstract: The current study deals with water quality variations and micro algal community structure in the highly eutrophic pond. Several water quality parameters were evaluated during the period from July 2014 to June 2015 from sampling station sited from Annamalai Nagar viz., Pasupatheswarar temple pond. The water quality parameters like Air and water temperature, turbidity, electrical conductivity, total dissolved solids, total alkalinity, pH, free carbon-dioxide, dissolved oxygen, biological oxygen demand (BOD), chemical oxygen demand (COD), calcium, magnesium, phosphate and nitrate were analysed. A total 29 species were observed during the study period of which 11 species from the class Cynophyceae, 9 species from the class Chlorophyceae, 6 species from the class Bacillariophyceae and 3 species from the class Euglenophyceae. Maximum species of the class Cyanophyceae were observed during study period. The Microcystis aeruginosa species observed in the pond indicates the signs of eutrophication of pond. The water quality parameters such as temperature, alkalinity, phosphate and nitrates are favourable for the growth of phytoplankton.

Abstract: Crinum defixum Ker - Gawler is a bulbous herb which has widely used in indigenous medicine for many diseases; mainly leaf and bulb extracts are of medicinal importance. Leaf extract is used as a treatment for pimples, body-ache, dropsy, carbuncle, paronychia, leprosy, fever and diarrhoea. The bulbs are crushed and applied on to piles and itching. The present study to determine the possible phytochemicals and antimicrobial activity of various leaf extracts of Crinum defixum Ker - Gawler plant. The phytochemical screening demonstrated the presence different types compound like flavonoids, tannins, phenolic compounds, saponins and glycosides. The ethanol, methanol and crude extracts of Crinum defixum Ker - Gawler showed significant antibacterial activity against Escherichia coli, Staphylococcus aureus, pseudomonas aeruginosa, proteus vulgaris and antifungal activity against Candida albicans, Aspergillus flavus when compare to different concentrations (μg/mL). The antimicrobial potential of test compounds was determined on the basis of mean diameter of zone of inhibition around the disk in millimetres. Thus, the present findings revealed the medicinal potential of Crinum defixum Ker - Gawler to develop a drug against various human ailments.

Abstract: The knowledge behind the culture and beliefs of indigenous community needs to be harnessed and should be used to complement the modern technologies and policies for better and sustainable use of biological resources and increase resilience of the sector associated. The main objective of the current research was to study Jhum (Traditional Shifting Cultivation System) and the cycles and culture associated with it. The study was done in northeast Himalayan region of India and phenomenological approach was used. The research reveals that Jhum is the component of traditional agro-ecosystem encompassing diverse set of knowledge and practices of indigenous and local communities embodying traditional life-styles relevant for the conservation and sustainable use of natural resources for their livelihood. The cycle associated with the system reflects the synergy of practices with the natural phenomenon and indicators. Contrary to common modern belief, Jhum is carbon sink, maintain soil health, preserve biological diversity and sustain local climate. Forest clearing during Jhum is not deforestation but forest modification allowing forest regrowth during sufficiently long fallow. Fundamentally, Jhum as a system is an integrated approach to establish agro-ecosystem in the difficult terrains of tropical hill regions that involve forest, soil, biodiversity and livestock management through their culture, tradition and rituals that coevolved with associated ecosystem. Instead of being threat to climate or environment, the system can provide deeper insight into the many different aspects of sustainable and climate resilient development; and the interrelated role of local peoples and their cultures.

Abstract: The high prevalence of malaria in Africa has defiled many strategies aimed at its eradication. Researchers from various fields have tried without success in this fight against mosquito and its malaria disease. Annually billions of dollars are spent in the design of programs which are aimed at combating this dreaded disease. However all this spending seems to go down the drain as malaria and its vector mosquitoes celebrate their unflinching victory. Current control measures focusing on ways of preventing the disease vis-a-vis, protect man from the vectors “anopheline mosquito” are the mainstay of malaria prevention and control. Many of these control measures are operational with each contributing in its little way. The use of Long Lasting Insecticide Treated Nets (LLITN) and Indoor Residual Sprays (IRS) are well established strategies with global recognition and currently ongoing in Africa. However, as a result of shortcomings in these major control measures, new strategies with hopes of blissful success are been sought after. Larviciding (abortion of metamorphosis) and constant and adequate environmental sanitation seems to be the next option available for use. This article therefore takes a look at the vector-anopheline mosquito, its ecology, productivity and distribution. It also considers malaria and the various control and preventive measures currently targeted at its eradication.

Abstract: Methanol and ethanol extract showed antibacterial activity in range of 0-11 at 10 mg/mL at against all tested bacterial species. Methanol extract with amoxicillin exhibited effective inhibition E. coli. This combination showed antagonistic effect against B. subtilis and S. aureus. Interaction of ethanol extract with amoxicillin also showed effective inhibition against E. coli and decreased activity against B. subtilis and S. aureus.Methanol extract did not show inhibition against P. aeruginosa but it enhanced activity of ciprofloxacin on combination. Ethanol extract also exhibited effective inhibition against P. aeruginosa on combination with ciprofloxacin. But antagonist effect was observed on interaction of both extract with ciprofloxacin against other bacterial species.Interaction of methanol and ceftazidime showed mostly decreased or indifferent effect against all bacterial species. Ethanol extract with ceftazidime resulted in higher inhibition against E. coli. Combination of methanol extract with erythromycin showed higher inhibition against E. coli and also very effective inhibition against S. aureus. This combination resulted in decreased activity against B. subtilis. Ethanol extract with erythromycin also showed synergistic effect against S. aureus and effective inhibition against E. coli. These results indicate that both methanol and ethanol extract has potential to enhance the combination effect with erythromycin against S. aureus and E. coli.

Abstract: Current study was undertaken to highlight the effect of pruning on improving vigor of old orchards and increasing performance in terms of fruit yield and quality under water and nutrient stressed condition of mid hills of Eastern Himalaya. Guava was taken for the case study and all the physical and chemical properties of the fruits and other attributes of plant were evaluated using standard methods under three pruning intensities (light, moderate and severe) and no pruning. The emergence of bud was earliest in severe pruning, number of buds per shoot was highest with light pruning and cumulative lengths of new shoots were found to be highest in severe pruning. Fruit yield, size and weight were found to increase with pruning intensities and lowest in case of no pruning. Regarding chemical properties, total soluble solids and total sugar found to increase with enhanced pruning severity and least in case of no pruning. Acidity was found to be highest with no pruning and decrease with increase in pruning intensities. Overall pruning found to have rejuvenating impact on aged trees due to better light interception leading to better photosynthetic rate, better nutrient and water supply with reduced canopy and better quality yields.

Abstract: The Vibrio is the most common genera with crustaceans often causing various diseases in Aquaculture and significant economic losses. Many Vibrio species are pathogenic to human and have been implicated in food borne diseases. The present study was carried out, the isolation and identification of pathogenic bacterial flora were isolated from infected in hepatopancreas of vannamei. The SPDS Oceanic farm, RS Aqua farm of and Valli vilas Aqua farm Vellar estuary, Cuddalore District, Tamil Nadu, during the period of (September 2013 to November 2013). The collected samples were plated on TCBS- (Thiosulfate-Citrate-Bile salt-Sucrose) agar medium. The present study, totally 253 green colonies were isolated from TCBS agar plates and among these, 175colonies were identified by using the biochemical tests showed the V. parahaemolyticus, V. mimicus, V. vulnificus, V. damsela and P. shigelloides. The maximum species was recorded in V. parahaemolyticus (83.4 %) and minimum was observed in V. mimicus (1.7 %).

Abstract: Climate change arising from anthropogenic driven emissions of greenhouse gases has emerged as one of the most important environmental issues in the last two decades. One of the most significant potential consequences of climate change may be alteration in regional hydrological cycle and river flow regimes. Increased temperature is expected to increase the peak flows in snow-fed rivers of Himalayas. The changing pattern of regional temperature on flood peaks deserves urgent and systematic attention over a basin which provides an insight view of historical trends. Lower reaches of Satluj River is selected for the present study. Testing the significance of observed trends in flood peaks has received a great attention recently, especially in connection with climate change. The data series available was 48 years (1967-2010). The records were subjected to trend analysis by using both non-parametric (Mann-Kendall test) and parametric (linear regression analysis) procedures. For better understanding of the observed trends, flood peaks were computed into standardised flood peak indices (SFPI). These standardised data series were plotted against time and the linear trends observed were represented graphically. The analysis of flood peaks at different observation stations in lower reaches of Satluj River showed a large variability in the trends and magnitudes. The trend analysis results of flood peaks and gauge heights indicate that the flood peaks at all sites i.e. Rampur, Suni and Kasol show increasing but statistically insignificant trends. The trends in gauge height at all sites are also showing increasing trend but Kasol is statistically significant at 95% confidence level. The fast melting of glaciers, incessant monsoon rainfall and the synchronisation of the discharge peaks are the main causes of river floods. The past flood peaks will help us to observe the frequency of occurrence of floods in certain region and to determine whether the flood peaks in the past have been same with that of the present or whether there is any deviation in the trend in relation to climate change. Such studies will help in designing mitigation and adaptation strategies towards extreme hydrological events.

Abstract: Ambient temperature and relative humidity are two crucial climatic factors that heavily influence poultry production and management. Knowledge of the period during which the environmental conditions remains detrimental is crucial for successful and economic poultry production and resource management. The objective of the study is to identify and comparatively assess the most crucial months/periods during which the climatic condition hinder normal performance of dual purpose Vanaraja poultry in topographically and agro-climatically distinct locations. The average monthly temperatures and humidity of each location were compared with established critical limits of ambient temperature and relative humidity that influence poultry for the location. Results reveal that there are wide inter-location variations in sensitive period during the year and affect the performance of the introduced poultry with varied intensity. Also the cultural & management practices should be location-specific with incorporation of need-based seasonal modification leading to optimum resource use. With critical periods in mind farmers can adopt/frame appropriate and well-timed management practices to alleviate impact of adverse environmental conditions.

Abstract: Fungi may cause internal decay, cankers, loosening of tissue and cell walls result into weak forks in the trunk and large branches. Tree rot may be associated with root decay, damage to foliage and fruits. Wood decay fungi isolated from Tamarindus indica were Daldinia concentrica, Schizophyllum commune, Flavodon flavus, Irpex hydnoides, and Phellinus fastuosus, in which D. concentrica causing canker rot is reported for the first time from India and F. flavus and I. hydnoides P. fastuosus are recorded for the first time on T. indica wood causing white rot. During canker rot, formation of bark canker and extensive internal decay of wood was observed; as a result the tree growing in the M.S. University campus became structurally unstable and broken off at the canker face. Early detection and removal of such hazardous branches of trees is advocated to avoid loss of life and property.