Assessment of the Biodegradation of Herbicides by Bacteria Isolated from the Soil
Aim: The aim of this research is to assess the biodegradation of herbicides by bacteria isolated from the soil.
Study Design: This study is designed to isolate, identify and characterize bacteria from the soil, to determine the degradation of herbicides by the bacterial isolates.
Place and Duration of Study: Department of Microbiology, Nasarawa State University Keffi, Nasarawa State, Nigeria, between January 2017 and December 2017.
Methodology: Bacteria were isolated from two different soil samples using pour plate method. The isolated bacteria include the species of Bacillus, Pseudomonas and Staphylococcus aureus which were grown on three different herbicides, containing mineral salt medium to determine their biodegradation potential. And degradation was measured by optical density checked using a spectrophotometer at 3 days interval.
Results: The result revealed degradation of the herbicides by the isolates. All isolates were able to utilize the glyphosphate in the medium and as such growth was noticed. Out of the three isolates used (Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus), the best degradation observed was by B. subtilis at 82.61% on glyphosphate, followed by P.aeruginosa at 69.67% on Glyphosphate and finally S. aureus at 47.83% also on glyphosphate. The result also revealed low percentage degradation of the other herbicides by these organisms. Microorganisms were able to degrade glyphosate due to their ability to utilize the organophosphorus as the sole phosphorus source.
Conclusion: From this study it can be deduced that the isolated bacteria can be used for bioremediation of herbicide contaminated and polluted soil although further studies may be required to standardize the procedure.
Study on Morphological Characters of Four Cassava (Manihot esculenta Crantz) Varieties as Cultivated in Fafen District, Ethiopian Somali Regional State
Cassava (Manihot esculenta Crantz) is a multifunctional shrub such as food, feed, and raw materials in industries. There are many studies but limited on their morphological characters in Ethiopia. In particular, as cassava is newly introduced into Ethiopian Somali Region, each variety is not well known by their morphological appearance. Morphological characters have not yet been documented for underused varieties, but important to choose varieties for breeding and conservation. Therefore, the aim of this study is to study of morphological characters of cassava varieties. To do so, four cassava varieties (kello, Qulle, Hawasa-4 and Chichu) were obtained from Hawasa Agricultural Research Center and planted in fafen district. Thirty centimeter long stakes were planted with 1m x 1m intra and inter row spacing with Randomized Complete Block Design. There were four rows, five plants per row and six plants per plot and used to collect qualitative and quantitative data at 3rd, 6th and 9th months after planting. According to the analyzed data, results revealed that all of the varieties have stipules and fully prominent leaf scars. Almost the same shape of the central leaflet, apical leaf color and trichotomous branching habit were observed in three of the varieties whereas color of leaf vein, petiole, matured leaf and stem exterior were different across varieties. Not only qualitative traits but also quantitative traits (size of leaf scars, distance between foliar scars, a distance of first branching, the height of plant and number of secondary branches) show highly significant variation among cassava varieties. In general, cassava varieties had different characters with most morphological traits and similar with some of them. Therefore, aerial morphological traits are used to distinguish between cassava varieties and are the first step in molecular studies. However, morphological traits are changing with the changing environment. Therefore, gene-based diagnosis should be conducted to ensure their relations.
Due to rapid advancement in molecular technique, the use of molecular markers in distinctness, uniformity and stability (DUS) testing as a complement to replacement of morphological observations became the subject of great interest in scientific studies and consequently topic for discussion within International Union for the Protection of New Varieties of Plant (UPOV). The present study involved 14 hybrids and OPVs that were scored for 32 DUS character prescribed by UPOV and genotyped with 56,110 SNPs where 36,100 had no missing data (no amplification) using Trait analysis by association, evolution and Linkage (TASSEL) software to relent any polymorphic of the single nucleotide polymorphism (SNPs) covering all the ten chromosomes of maize genome. Mean polymorphic information content (PIC) was found to be 0.15 and ranged from 0.09 to 0.19. Mean heterozygosity was found to be 0.41 and a range of 0.25 to 0.51, and gene diversity mean of 0.20 with a range of 0.12 to 0.26. Dendrogram constructed showed established differences among the individuals with the desired characters. Heterozygosity showed that inbred lines used to develop these varieties need to be worked for purification for further breeding program.
Silico Analyses of Antioxidant-Related Compounds on Selected Medicinal Plant Cordia macleodii Enzyme-Based Targets
A great number of medicinal plants phytochemicals are reported as good anti-oxidant from several studies. However, their modes of action are still not known properly. The lack of molecular studies could be considered an impediment for studies seeking to improve anti-oxidant-based drug design. The present computational study allows us to make important observations about the molecular details of the binding modes of a set of anti-oxidant against Cordia macleodii secondary metabolites drug-enzyme targets Super oxide dismutase, Catalase, Glutathione peroxidase. Through molecular docking it was found that two Cordia phytocompounds are promising leads for the anti-oxidant enzymes binding with active metal site domain, and exhibited better affinity towards active site pocket binding. In addition, the affinity values were collected by principal component analysis and drug-likeness properties were checked to identify the strongest-docking phytochemicals. The results are an excellent starting point for future studies of structural optimization of this kind of compounds.
Development of Black Soldier Fly, Hermetia illucens (Diptera: Stratiomyidae) in Selected Organic Market Waste Fractions in Accra, Ghana
Aims: To assess the effect of organic waste and their formulations on the development of the black soldier fly larvae.
Study Design: The experiment used one time feeding (lump feeding) of feedstocks obtained from organic market waste fractions and their combinations. The arrangement of composting containers followed a Randomized Complete Block Design (RCBD), replicated three times.
Place and Duration of Study: The study took 3 months and was conducted at the BSF laboratory of the Soil and Environmental Science Research Centre, Biotechnology and Nuclear Agriculture Research Institute of the Ghana Atomic Energy Commission in Accra, Ghana, West Africa.
Methodology: Two hundred and forty (240) hand counted 5-day old BSF larvae were inoculated onto 2 kg each of organic market waste fractions and their combinations in 60 L plastic containers covered with a mesh. Equal quantities of the above feedstock without larvae served as control. The arrangement of the containers followed a Randomized Complete Block Design (RCBD), replicated three times. Moisture content, larval growth parameters, temperature, relative humidity, prepupal development were recorded.
Results: Whiles moisture contents of most of the feedstock decreased gradually over the trial period, that of fruit waste only, fruit waste + corn husk and fruit waste + vegetable waste increased with time and was higher at the end of the trial than at the beginning. Composting temperature in all the feed stocks never reached the thermophilic stage and was between 29 – 38°C. The lowest temperature of 28.88°C was recorded in the mixture of vegetable waste and fruit waste whiles the highest, 37.55°C was recorded in the mixture of corn husk and uncooked food waste compost. Composting humidity ranged between 59 and 87% with significant differences being observed across treatments on days 0, 10, 15, 20 and 25. Larvae reared on a mixture of all the feedstock was significantly the heaviest (176.66 mg). Significant differences were observed in larval length and those fed with a mixture of fruit waste and uncooked food waste were the longest (17.66 mm). A highly significant number of eclosed adults, number of females and the number of egg clutches were observed among treatments.
Conclusions: Vegetable waste only, fruit waste only and a combination of vegetable waste + uncooked food waste; fruit waste +uncooked food waste; and a combination of all the wastes were the most preferred organic waste as they produced the optimum larval characteristics. The composting bins should be fitted with an outlet for leachates from the compost to drain out to avoid increase in compost moisture which will create anaerobic conditions that might delay compost maturity.
