Asian Journal of Biology

Pepper (Capsicum annuum L.) is an important fruit vegetable belonging to the family Solanaceae. The demand for this crop as a vegetable has increased especially in the urban centres, however, availability of quality seeds for sustainable production to meet the high demand has become a big challenge. The objective of this study was to investigate the influence of three storage environments on germination and vigour of pepper seeds. The experiment was arranged in 2 x 3 x 4 factorial using completely randomized design (CRD) in three replication. The factors were two accessions of pepper, three storage environments and four storage periods. The laboratory experiment was carried out at The National Centre for Genetic Resources and Biotechnology (NACGRAB) Ibadan, Nigeria starting from April 2015 to January 2016 which constituted four storage periods. The stored seed samples were drawn at three-month intervals and evaluated for germination and germination index. Analysis of variance (ANOVA) revealed that the effects of accession, storage environment and storage period were highly significant (P< .01) on germination of pepper seeds. Similarly, the effects of accession and storage environment were highly significant (P<.01) on germination index. The germination percentage for accession NGB 001010 was significantly higher (68.9%) than accession NGB 001066 which had germination percentage of 61.1%. In addition, germination index for NGB 001010 was significantly lower (5.3 days) compared with that of NGB 001066 which took about 5.9 days to germinate.  Seeds stored under ambient conditions gave the lowest germination percentage (53.4%) and highest germination index (6.1 days). The germination percentages of seeds stored under short (70.3%) and medium (71.3%) term conditions were not significantly different. Similarly, germination index of seeds stored under short (5.6 days) and medium (5.5 days) term conditions were not significantly different. Moreover, germination declined as the storage time increased. The study suggests both short-term (15.1 to 21.3⁰C) and medium term (-4.2 to 3.4⁰C) conditions as effective storage environments for storing pepper seeds. In addition, the seeds must be stored inside moisture-prove packaging materials.

In recent years, there has been an increased interest in the sperm preservation and maintenance of genetic resources of small ruminants. The study aimed to determine and compare the preservation effects of skim milk and Tris-citrate on the quality of chilled and frozen-thawed indigenous ram semen (n=13) during rainy monsoon season (June to October) in Bangladesh. Semen was collected from four indigenous rams by artificial vagina method to observe motility, viability and membrane integrity at 0, 24, 48, 72 hrs of storage. The hypo-osmotic resistance test (HOST) was used to evaluate the sperm membrane integrity. The ejaculates were divided into two groups according to dilution with skim milk or Tris-citric acid egg yolk media for chilling and freezing. Motility, viability and membrane integrity were significantly (p<0.01) higher in chilled semen samples diluted with skim milk in comparison to those of semen diluted with Tris-based extender at all time-based observations. However, around 50% motility was preserved up to 48 hours by both extenders. Results also showed that motility, viability and HOST (+ve %) decreased drastically after cryopreservation irrespective of diluents. Similar to chilled semen, studied parameters were significantly higher (p<0.05) in frozen-thawed semen diluted with skim milk based extender, though quality parameter of frozen-thawed semen was not satisfactory. In conclusion, skim milk based extender appears to be a better option compared to Tris based extenders for chilling semen of indigenous ram up to 48 hours with acceptable quality. Whether the differences found between the extenders will be reflected in the fertility results after artificial insemination (AI) is yet unknown and needs to be further studied.

Major biological parameters along with nutrient concentrations of the Nile in Upper Egypt were analyzed during 2007 for a better understanding of community structure and diversity of the main functional groups of organisms. The abundance of plankton and zoobenthos was followed seasonally. Altogether 168 taxa (85 phytoplankton, 43 zooplankton and 40 zoobenthos) were encountered from the Nile in Upper Egypt. The combined contribution of chironomid larvae, Mollusca and Oligochaetae represented the abundant groups of the Nile zoobenthos throughout the study period. The results of this study suggested that the sediment contents of organic matter and CaCO₃, as well as water temperature and NO₃-N concentrations, seemed to be important in determining the abundance and biomass of zoobenthos. Most importantly, the results of this study will provide valuable information for river management. Simultaneously; alpha, beta, gamma and Shannon (H̀) diversities of these communities were measured. Alpha and gamma diversities for phytoplankton were higher than those of zooplankton or zoobenthos. Shannon diversity index for the different groups was relatively low due to the less water retention of the lotic ecosystem. The composition similarity of the investigated samples and the weak rate of species displacement among sites were reflected by β diversity.

A study was carried out on the antibacterial and antifungal properties of earthworms Eudrilus eugeniae paste and coelomic fluid against selected pathogens like Vibrio cholera, Vibrio parahaemoliticus, Bacillus subtilis, Staphylococcus aureus, Salmonella typhi, Escherichia coli,Candida albicans ,Aspergilus flavus, and Aspergilus niger. The study was conducted on School of Environmental Sciences, Kottayam. The coelomic fluid and paste of earthworms was screened against some human pathogenic bacteria including six bacterial strains and three fungal strains. The earthworm was collected by handsorting method. The earthworm paste were prepared and coelomic fluid was collected by heat and cold shock method   The antimicrobial activity was done through the agar well diffusion method. The result revealed that the antibacterial activity in earthworm paste shows that Escherichia coli, Bacillus subtilis, Staphylococcus aureus shows 16mm, 8mm,18mm diameter. The other bacterial isolates shows no zone of inhibition. The zone of inhibition of coelomic fluid against Escherichia coli, Bacillus subtilis and Staphylococcus aureus shows 10mm,14mm,16mm simultaneously. The Vibrio parahaemolyticus shows slight changes in the zone of inhibition area. Vibrio cholera and Staphylococcus typhishows no activity against paste and coelomic fluid of earthworm. The antifungal activity of earthworm Eudrilus eugeniae against fungal strains like Candida albicans, Aspergillus niger and Aspergillus flavus. The coelomic fluid of Candida albicans18mm shows high zone of inhibition compared to Aspergillus niger 16mm. The earthworm paste of Eudrilus eugeniae shows antifungal property against Aspergillus niger (14 mm). Aspergillus flavus shows no activity against paste and coelomic fluid of earthworm. The present work conclude that the Eudrilus eugeniae paste and coelomic fluid shows antibacterial and antifungal  properties against selected bacterial and fungal isolates  and suggests some of the coelomic fluid and pastes components might be useful for pharmaceutical applications.

Bacterial biofilms are associated with a large number of persistent and chronic infections. Biofilm-dwelling bacteria are particularly resistant to antibiotics and immune defenses, which makes it hard to eradicate biofilm-associated infections. This study aimed to analyze the effect of zinc sulphate (ZnSO₄) and bacteriophage treatment on E. coli biofilm. This study was performed in microbial biotechnology laboratory, SUST, Sylhet, Bangladesh during a period of 9 months from December 2016 to August 2017. Bacteria were isolated from clinical samples of renowned hospital and diagnostic center in Sylhet city, Bangladesh and identified using various biochemical tests. Biofilm forming isolates were screened by the crystal violet assay method in microtiter plate. Bacteriophage was isolated from drainage samples and recognized by spot test. Biofilm enhancement was studied using different concentrations of FeCl₃. Also, Biofilm inhibition was investigated using zinc sulphate (ZnSO₄) and bacteriophage separately and in combination by the enumeration of viable cells of biofilm after treatment in six (6) days experiment. Kirby-Bauer disk diffusion method was used for antibiotic susceptibility test. The result showed that biofilm formation was enhanced by the supplementation of 10 µM FeCl₃ in medium. A significant decrease (p ˂0.01) in viable cells of biofilm was occurred with highest reduction of 89±1% and 85.38±1.30% by zinc sulphate and phage treatment, respectively. Also, the combined use of zinc sulphate and phage caused significant removal (p ˂0.01) in viable cells of biofilm with highest reduction of 97.22±1.37% in comparison to control. However, there was significant difference (p <0.01) between combined treatment and single treatment. The antibiotic susceptibility test showed that selected biofilm forming isolate was resistant to antibiotics tested. Finally, it might be said that a combined approach of bacteriophage and iron antagonizing molecule is more significant than distinct approach for the eradication of E. coli biofilm.