•21 new complete cacao badnavirus sequences reconstructed de novo thanks to the NGS.•The taxonomic status of the molecular groups of cacao badnaviruses elucidated.•Ten species associated with cacao ...swollen shoot disease.
Cacao swollen shoot virus is a member of the family Caulimoviridae, genus Badnavirus and is naturally transmitted to Theobroma cacao (L.) by several mealybug species. CSSV populations in West African countries are highly variable and genetically structured into several different groups based on the diversity in the first part of ORF3 which encodes the movement protein. To unravel the extent of isolate diversity and address the problems of low titer and mixed viral sequences in samples, we used Illumina MiSeq and HiSeq technology. We were able to reconstruct de novo 20 new complete genomes from cacao samples collected in the Cocoa Research Institute of Ghana (CRIG) Museum and from the field samples collected in Côte d’Ivoire or Ghana. Based on the 20% threshold of nucleotide divergence in the reverse transcriptase/ribonuclease H (RT/RNase H) region which denotes species demarcation, we conclude there exist seven new species associated with the cacao swollen shoot disease. These new species along with the three already described leads to ten, the total number of the complex of viral species associated with the disease. A sample from Sri Lanka exhibiting similar leaf symptomology to West African CSSD-affected plants was also included in the study and the corresponding sequence represents the genome of a new virus named cacao bacilliform SriLanka virus (CBSLV).
Cassava (Manihot esculenta Crantz) is an important food crop in many tropical countries in Africa, South America and Asia. However, yields are below the productivity of the crop. This requires ...breeding and selection for improved varieties. The current study therefore investigated genetic diversity among some Ghanaian preferred accessions which could be used for breeding purposes. Genetic diversity of 43 cassava accessions was determined using 14 morphological descriptors and 20 SSR primer pairs. Principal component analysis (PCA) indicated that the first three principal components accounted for 72.7% of the total variation with PCA1, PCA2 and PCA contributing 46.6, 14.7 and 11.4%, respectively. The size of amplified alleles ranged from 75 to 350 bp, most of which were closed to the published values. The polymorphic information content (PIC) values ranged from 0.07 for SSRY181 to 0.75 for SSRY175, with an average of 0.52. Gene diversity was high and the average observed heterozygosity was 0.77. Both morphological descriptors and SSR markers were able to group the accessions into distinct clusters independent of locality of collection. However, where the morphological descriptors indicated some accessions were the same, SSRs markers were able to distinguish them into distinct genotypes with some located in different clusters. The wider genetic diversity observed using SSR markers would be valuable for efficient management of germplasm and for effective utilization of materials in breeding programmes to produce hybrids of desirable characteristics. Therefore, the application of morphological descriptors in management of germplasm should be backed by the use of molecular markers.
Fermentation of Theobroma cacao L. beans is the most critical stage in the production of cocoa products such as chocolates and its derivatives. There is a limited understanding of the complex ...response of microbial diversity during cocoa bean fermentation. The aim of the present study was to investigate microbial communities in the cocoa bean fermentation heap using a culture-independent approach to elucidate microbial diversity, structure, functional annotation and mapping unto metabolic pathways. Genomic DNA was extracted and purified from a sample of cocoa beans fermentation heap and was followed by library preparations. Sequence data was generated on Illumina Hiseq 2000 paired-end technology (Macrogen Inc). Taxonomic analysis based on genes predicted from the metagenome identified a high percentage of Bacteria (90.0%), Yeast (9%), and bacteriophages (1%) from the cocoa microbiome. Lactobacillus (20%), Gluconacetobacter (9%), Acetobacter (7%) and Gluconobacter (6%) dominated this study. The mean species diversity, measured by Shannon alpha-diversity index, was estimated at 142.81. Assignment of metagenomic sequences to SEED database categories at 97% sequence similarity identified a genetic profile characteristic of heterotrophic lactic acid fermentation of carbohydrates and aromatic amino acids. Metabolism of aromatic compounds, amino acids and their derivatives and carbohydrates occupied 0.6%, 8% and 13% respectively. Overall, these results provide insights into the cocoa microbiome, identifying fermentation processes carried out broadly by complex microbial communities and metabolic pathways encoding aromatic compounds such as phenylacetaldehyde, butanediol, acetoin, and theobromine that are required for flavour and aroma production. The results obtained will help develop targeted inoculations to produce desired chocolate flavour or targeted metabolic pathways for the selection of microbes for good aroma and flavour compounds formation.
Aims: To access the responses of 22 soybean genotypes under drought stress during the flowering stage of development.
Study Design: A completely randomized experimental design (CRD) was adopted in ...this study. Five seeds of each of the 22 soybean genotypes were planted in 12-liter (L) plastic buckets (with holes at the bottom) containing sandy loam soil. There was one genotype per pot with three replications. The setup was repeated to represent experimental (drought-stressed (DS) and control (well-watered (WW) groups.
Place and Duration of Study: Teaching and Research Farm of the School of Agriculture, College of Agriculture and Natural Sciences, University of Cape Coast, Cape Coast, Ghana in 2019.
Methodology: Twenty-one exotic soybean genotypes and a local variety were assessed for their responses to drought stress at the flowering stage of development using pot experiment in the greenhouse. One group (experimental) was exposed to drought stress by withholding water for 15 days whilst the other group (control) was watered regularly at three-day intervals. Data collected were the number of leaves, plant height, stem girth, leaf area, and number of flowers, at 5, 10, and 15 days after treatment (DAT) and relative leaf water content at 15 DAT. The number of days to permanent wilting of the genotypes was also recorded.
Results: Drought stress reduced the number of leaves and plant height significantly (P-values = 0.033, 0.000) and (P-values = 0.004, 0.000) at 10 and 15 days after drought treatment respectively. Also, stem girth, leaf area, and number of flowers were significantly reduced at all sampling dates (P-value = 0.002, 0.000, 0.000), (P-values = 0.004, 0.000, 0.000) and (P-values = 0.009, 0.000, 0.000) respectively. At 15 DAT, drought significantly (P < 0.001) reduced relative leaf water content. Genotypes TGX-1989-11F and TGX-1987-62F were the first and last to wilt at 7 days and 16 days after rewatering respectively.
Conclusion: The pot screening method revealed that the number of leaves, plant height, stem girth, leaf area, number of flowers, relative leaf water content, and days to permanent wilting differed significantly (P = 0.05) at 15 days of drought exposure.
Aims: The study aimed at the quantification, isolation and characterization of hydrocarbon degrading bacteria in oil-contaminated and pristine soils.
Methodology: Soil samples from petroleum ...hydrocarbon polluted sites at auto-mechanic workshops, a mechanic village, as well as pristine (control) soils, comprising of 14 sampling locations within Cape Coast Metropolis in the Central Region of Ghana were collected using standard sampling techniques. Collected soil samples were treated and cultured while enumerations, isolations and characterization of carbonoclastic bacteria associated were evaluated.
Results: Bacterial populations isolated from hydrocarbon-polluted sites had higher aerobic counts ranging from 7.24-8.02 log10 cfu/g of soil when compared with the pristine sites (from 6.79-7.61 log10 cfu/g of soil). Also, soil samples from the mechanic village (8.76 to 7.48 log10 cfu/g of soil) recorded more bacterial counts than those from the mechanic garages (8.02 to 7.24 log10 cfu/g of soil). The calculated percentage profiles of all the hydrocarbon utilizing bacteria in the total culturable heterotrophic bacteria were low throughout the study, even though the percentage scores were all above 50%. A total of 19 hydrocarbon degraders were isolated. The isolates identified belong to the genera Pseudomonas, Proteus, Bacillus and Enterobacter.
Conclusion: The outcome of the study based on the bacteria populations, identification profiles, coupled with their survival and multiplications in designated medium amended with crude oil as the carbon and energy sources, suggest their petroleum hydrocarbon degrading capabilities, hence may be used in bioremediation applications.
The concept of e-Agriculture has become prominent in recent times as a mechanism for the modinization of agriculture especially in developing nations like Ghana. The concept encompasses the creation ...of a platform for utilizing Information and Communication Technology (ICT)-mediated tools by practitioners such as extensionists and farmers to promote agricultural production and productivity. A key component of e-Agriculture is the use of mobile phones in agriculture. In Ghana, there is little knowledge of the factors driving access and usage of mobile phones by farmers and the associated impact on household crop income. To provide empirical evidence of mobile phone access and usage and the impact on crop income, this study was carried out relying on data from 2,662 respondents. Specifically, the study categorized mobile phone usage into agricultural and non-agricultural use. Multinomial endogenous treatment effect model was employed to assess the drivers of mobile phone usage and the impact of usage on crop income. The results showed that cost of airtime, location of the household, and access to electricity significantly influenced mobile phone usage for both agricultural and non-agricultural purposes. Furthermore, gender, educational status, and livestock ownership significantly influenced mobile phone usage for agricultural purposes. With regard to impact, the results showed that crop income increased with mobile phone usage, with a higher-income effect for agricultural usage. The study therefore recommends that the National Communication Authority (NCA) should partner with telecommunication companies to ensure that mobile network connectivity is made available and accessible to rural communities to promote mobile phone usage. Also, extension agents should adopt the use of mobile phones to render extension services in order to reach more farmers. Meanwhile, reducing the tax on airtime for rural dwellers will go a long way to promote mobile phone usage and increase crop income.
Medicinal plants are used by traditional practitioners to treat several ailments. Ethnomedicinal studies on Trema orientalis Linn. Blume (Ulmaceae) have shown that it is used in the treatment of ...diabetes mellitus, respiratory diseases, oliguria, and malaria. This article is aimed at providing comprehensive information on the medicinal uses, biology, phytochemical constituents, and pharmacological data available on T. orientalis. This has been done to explore its therapeutic potential for future research opportunities. This review was compiled with information obtained from databases such as Medline, Elsevier, Springer, Science Direct, Pubmed, Google Scholar, and a library search for articles published in peer-reviewed journals. Compounds present in the plant include tannins, saponins, flavanoids, triterpenes, phytosterols, and several constituents of xanthones. Some pharmacological research done on the plant has focused on, hypoglycemic activity, analgesic, anti-inflammatory activities, anti-plasmodial activity, diuretic activity, laxativity effect, anti-convulsant activity, anti-helmintic activity, anti-sickling effect, anti-oxidant, and anti-bacterial activity. This compilation strongly supports the view that T. orientalis has beneficial therapeutic properties, and indicates its potential as an effective herbal remedy for several diseases. The promising results from several research works could be further substantiated by clinical trials.
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