Boron levels in soils cropped to coffee and their relationships to some soil properties in Ghana

Studies on boron levels in soils cropped to coffee were carried out in Ghana due to widespread reports on boron deficiency in soils of some coffee producing countries. Leaves and soils were sampled from Cocobod coffeeplantations at Bogoso, Suhuma, Manso-Mim, Bunso and Bepong, which represent the main coffee growing areas in the Western, Ashanti and Eastern regions of Ghana. Also determined were percent OC and Ca, pH, texture and statistical relationships established for both leaf and soil boron contents and the soil properties. The results showed that availableB in the 0-30 cm depth ranged from 0.77 to 1.54 mg B kg-1 soil. Surface soil pH values ranged from 5.4 to 6.8 and the subsurface soil from 5.1 to 6.7. Leaf B was between 28.7 and 42.5 mg B kg-1. The leaf Ca/B ratio used as index of B deficiency was between 331.4 and 398.8; values high enough to suggest that boron was low compared to Ca concentrations in the leaves, a condition which implies that available B in the soils was below the levels required to support coffee plants. All locations of sampling indicated that there was positive correlation between percent OC,calcium and available B in the surface soils. Similarly, the relationship between percent clay, calcium and available B in the subsurface soils was positively correlated. Soil available B at 0–30 cm depth was highly influenced by percent OC and pH. Coffee leaf B content and soil pH was negatively correlated at pH above 5.8, but was positive when the pHwas below 5.8. Boron levels in the coffee leaves were within the critical range of 2–40 mg B kg-1 although soil available B appeared low

Impact of shade and cocoa plant densities on soil organic carbon sequestration rates in a cocoa growing soil of Ghana

Cropping systems have influence on the conservation of soil organic matter. Soil samples were taken from a long term experiment that was designed to study the impact of shade and cocoa plant densities on cocoa yields. The impact of the treatments on soil organic carbon sequestration rates and the gains or losses of soil organic carbon under the treatments with reference to adjacent undisturbed bush were assessed. The experiment was sited at the Bunso substation of the Cocoa Research Institute of Ghana on Rhodi-lixic ferralsol with annual precipitation of about 1500 mm. The shade was provided by forest trees of 18 trees ha-1 and no shade, while the cocoa densities were 1111, 1428 and 1667 trees ha-1. Shade effects on organic carbon pools within the top soil (0-30 cm) under cocoa were not significant (p=0.05). Cocoa plant densities per unit area influenced the soil organic carbon pools. The soil organic carbon pools were significantly lower (p=0.05) in the closely planted farms than in the widely spaced farms. There were no soil organic carbon sequestration in the highest cocoa plant density of 1667 trees ha-1 but 250 and 190 kg soil organic carbon ha-1 yr-1 in the top soil (0-15 cm) were sequestered in the soils under cocoa with density of 1111 trees ha-1 for shaded and unshaded farms respectively. Irrespective of the shade conditions, the net gains of carbon in the soils were higher in farms with lower cocoa plant density. The results suggest that cocoa planted at low plant density under shade stores more carbon per unit area of soil than an equivalent area of cocoa planted at high density without shade. It is concluded that cocoa farming could be an effective means to mitigate carbon dioxide emissions in cocoa growing countries.Key words: Soil organic carbon, sequestration rates, cocoa plant density, shade

Relative efficacy of cocoa pod husk-based compost on growth and nutrient uptake of cocoa seedlings in the nursery

The effect of cocoa pod husk-based compost on growth and nutrient uptake of cocoa seedlings was compared with conventional NPK 15-15-15 fertilizer at the nursery in a randomized complete block design experiment. Poly bags were filled with either top soil or compost alone, and also with mixtures of top soil, compost and inorganic fertilizer in various ratios to provide the following treatments: soil alone, compost alone, 1 : 1 soil/compost, soil + fertilizer, 1 : 1 soil/compost + fertilizer, 1 : 2 soil/compost, 1 : 2 soil/compost + fertilizer, 2 : 1 soil/compost, 2 : 1 soil/compost + fertilizer. The fertilizer was added at the rate of 6 g per poly bag. Plant height, girth, leaf area, dry matter yield, and root volume of cocoa seedlings were significantly (P<0.05) affected by the potting media at 24 weeks after sowing. Potting media with the fertilizer additions significantly (P<0.05) produced shorter seedlings with smaller stems and narrower leaves. Root volumes and total dry matter yield of seedlings positively correlated (r = 0.733), and were significantly (P<0.05) higher in soil/compost mixtures than in treatments with fertilizer additions. Irrespective of the potting media, the uptake of N by the seedlings was higher than P and K. However, the addition of fertilizer to the potting media with compost resulted in lower N uptake by the seedlings. The use of compost developed from cocoa pod husk as potting medium or soil amendment for nursing cocoa seedlings enhanced better seedling growth than when used in combination with NPK 15-15-15 fertilizer

Effect of polybag size and foliar application of urea on cocoa seedling growth

The effects of different polybag sizes and foliar application of urea on the growth of cocoa seedlings in the nursery were studied at the Cocoa Research Institute of Ghana substation at Afosu in the Eastern Region of Ghana between June 2004 and May 2005. Hybrid cocoa seeds were sown in polybags measuring 17.5 cm × 25 cm, 12.5 cm × 25 cm, 12.5 cm × 20 cm, and 12.5 cm × 15 cm filled with top soil. From the four-leaf stage, half of the seedlings in the different polybags received fortnightly foliar application of 2 per cent urea solution, while the other half did not receive foliar application of urea. Each treatment consisted of 50 cocoa seedlings. There were significant differences (P< 0.01) in girth and height between the cocoa seedlings in the different sizes of polybags at 3, 4 and 5 months after sowing. Leaf number and tap root length were also significantly influenced by polybag size at 4 and 5 months after sowing. Generally, seedlings raised in 17.5 cm × 25 cm polybags produced bigger and taller seedlings, more leaves, longer tap root length, and had significantly higher (P< 0.01) total dry matter per seedling than those raised in 12.5 cm × 15 cm polybags. Foliar application of 2 per cent urea improved the growth of cocoa seedlings in all the different polybag sizes. The results suggest that smaller polybag sizes (12.5 cm × 25 cm, 12.5 cm × 20 cm, and 12.5 cm × 15 cm) could be used to nurse cocoa seedlings and transplanted early at 3 months after sowing instead of the recommended practice of nursing in 17.5 cm × 25 cm polybags and transplanting at 5 to 6 months after sowing. More cocoa seedlings raised in smaller polybags could, therefore, be transported per trip for field planting at reduced cost to the farmer.Les effets de différentes dimensions de sac en plastique et d\'application foliaire d\'urée sur la croissance de semis de Cacao dans les pépinières étaient étudiés à Afosu, une sous-station de l\'Institut de Recherche en Cacao du Ghana dans la région de l\'Est du Ghana entre juin 2004 et mai 2005. Les fèves de cacao hybride étaient semées dans les sacs en plastique qui mesuraient 17.5 cm × 25 cm, 12.5 cm × 25 cm, 12.5 cm × 20 cm, et 12.5 cm × 15 cm remplis de couche arable. De la phase de 4-feuille, une demie de semis dans les différents sacs en plastique recevaient tous les quinze jours l\'application foliaire de 2% de solution d\'urée alors que l\'autre demie ne recevaient pas d\'application foliaire d\'urée. Chaque traitement consistait en cinquant de semis de cacao. Il y avaient des différences considérables (P £ 0.01) en circonférence et en taille entre les semis de cacao dans les différentes dimensions de sacs en plastique à 3, 4 et 5 mois après la semaille. Nombre de feuille et la longueur de racine pivotante étaient aussi considérablement influencés par la dimension du sac en plastique à 4 et 5 mois après la semaille. En général les semis élevés dans les sacs en plastique de 17.5 cm × 25 cm produisaient des semis plus gros et plus grands, plus de feuilles, de longueur de racine pivotante plus longue et avaient une totalité de matière sèche par semis considérablement plus élevées (P £ 0.01) que ceux élevés dans les sacs en plastique de 12.5 cm × 15 cm. L\'application foliaire de 2% d\'urée améliorait la croissance de semis de cac ao dans toutes les différentes dimensions de sacs en plastique. Les résultats suggèrent que les sacs en plastique de dimensions plus petites (12.5 cm × 25 cm, 12.5 cm × 20 cm, et 12.5 cm × 15 cm) pourraient être utilisés pour soigner les semis de cacao et repiqués précoces à 3 mois après la semaille plutôt que la pratique actuelle recommandée de soigner dans les sacs en plastique de 17.5 cm × 25 cm et repiquer à 5-6 mois après la semaille. Plus de semis de cacao élevés dans les plus petites sacs en plastique pourraient donc être transporter par trajet pour le repiquage sur le terrain à coût réduit à l\'agriculteur. Ghana Journal of Agricultural Science Vol. 40 (2) 2008: pp. 207-21

Amounts of NPK removed from soil in harvested coffee berries as guiding baseline for planning fertilizer requirements of coffee in Ghana

Monthly samples of ripened improved robusta coffee berries from compact and large growth forms from three locations, which are representative of the main ecological zones where coffee is grown in Ghana, were taken for 3 years. The pulp and parchment and beans were analysed for N, P and K contents. The amounts of N, P and K removed from the soil in the harvested coffee berries were estimated from the concentrations of the nutrients in the pulp and parchment and beans, and the yield of coffee at each location. The mean NPK contents of the berries were 2.18, 0.08, 2.56 and 2.07, 0.08, 2.52 per cent for compact and large growth forms, respectively. The N and P concentrations in the pulp and parchment were lower than in the bean, while the K content was higher in the pulp and parchment than in the bean across the locations. The N, P and K concentrations of the coffee berries were not significantly different among the growth forms. Coffee berries from suitable and moderately suitable sites removed significantly (P&lt;0.05) higher amounts of N and K than the berries from the marginally suitable site, while the P contents of the berries were significantly (P&lt;0.05) lower than N and K across the locations. Regardless of the coffee growth forms, the demand for N and K may be higher than P. A fertilizer rate of 30 kg N, 1 kg P, and 33 kg K ha-1 may serve as a basis for planning fertilizer requirements of mature coffee in Ghana

Effect of weed control methods on some soil properties of a newly planted cocoa farm

Weed control constitutes a high percentage of the total field maintenance cost of newly planted cocoa. Soil samples were collected from an experiment that was designed to evaluate some weed control methods during cocoa establishment. The objective of the experiment was to assess the effect of the weed control methods on microbial biomass and extractable N and P contents of the cocoa-growing soil during cocoa establishment. The weed control treatments were clean weeding, two times per year; clean weeding, three times per year; clean weeding, four times per year (recommended practice); high slashing, four times per year; clean weeding (1 m wide), three times per year plus Mucuna pruriens cover crop; clean weeding, three times per year plus Flemingia congesta mulch; Gramoxone 1.5 l ha-1, four times per year; and Roundup 1.5 l ha-1, three times per year arranged in a randomized complete block design. Microbial biomass N content ranged from 10.8 to 42.5 mg N kg–1 soil. Microbial biomass N was significantly higher (

Assessment of the Acceptability of Sewage-cultured Fish Using Bacteriology and Social Responses at Gbalahi

This study focused on the suitability of using sewage treatment ponds at Gbalahi, a suburb of Tamale in the northern region of Ghana, to convert residual organic nutrients into quality animal protein through pisciculture. Two tilapia species O. niloticus (Linnaeus, 1758) and S. galilaeus (Linne, 1758) was evaluated and compared under identical conditions in hapas installed in five sewage treatments ponds. The microbiological enumeration showed that, total coliform bacteria were in higher levels (600-42000 cfu) than faecal coliform bacteria (64-8400 cfu) in all the ponds. The levels of faecal coliforms compared to the safe level (5000 cfu) set by the Environmental Protection Agency (EPA) of Ghana, showed that fish from the ponds are safe for human consumption. However many people (44% of a total of 400) rejected sewage cultured fish because of high bacterial presence which could pose health hazards. Majority (60%) of the 1000 respondents would eat fish from sewage ponds even though about 80% of those who would eat sewage cultured fish were poor. The 40% who would not eat sewage-cultured fish were the rich

Sewage Fish Culture as an Alternative to Address the Conflict between Hunters and Hunting Communities in Northern Region

The people of Tamale in the Northern region of Ghana also hunt as a recreational or traditional or hobby at weekends during the dry season. Wild animals are indiscriminately killed and this poses a threat to the wildlife populations in the country. The conflict between hunters and hunting communities, the dangers involved in communal hunting, the occasional loss of lives, the destruction of the plant cover and the burning of farms is an indication that an alternative is necessary. Sewage fish culture is one of such alternatives. Human faeces are an effective fattening diet for fish.  Sewage-fed ponds contain high levels of N, P, Ca, and K (Pacey, 1978) and can produce as high as 7-10 t/ha/yr of fish (FAO, 1994) depending on the sewage retention time (Kalbermatten et al., 1982). The use of sewage for fish culture has the potential to defray the costs of sanitation and sewage treatment processes in Tamale and other towns and cities in Ghana

High prevalence of multidrug-resistant tuberculosis among patients with rifampicin resistance using GeneXpert Mycobacterium tuberculosis/rifampicin in Ghana

AbstractObjective/BackgroundDrug-resistant strains of tuberculosis (TB) represent a major threat to global TB control. In low- and middle-income countries, resource constraints make it difficult to identify and monitor cases of resistance using drug susceptibility testing and culture. Molecular assays such as the GeneXpert Mycobacterium tuberculosis/rifampicin may prove to be a cost-effective solution to this problem in these settings. The objective of this study is to evaluate the use of GeneXpert in the diagnosis of pulmonary TB since it was introduced into two tertiary hospitals in Ghana in 2013.MethodsA 2-year retrospective audit of clinical cases involving patients who presented with clinically suspected TB or documented TB not improving on standard therapy and had samples sent for GeneXpert testing.ResultsGeneXpert identified 169 cases of TB, including 17 cases of rifampicin-resistant TB. Of the seven cases with final culture and drug susceptibility testing results, six demonstrated further drug resistance and five of these were multidrug-resistant TB.ConclusionThese findings call for a scale-up of TB control in Ghana and provide evidence that the expansion of GeneXpert may be an optimal means to improve case finding and guide treatment of drug-resistant TB in this setting

Co-infection of HIV in patients with Buruli ulcer disease in Central Ghana.

BACKGROUND: Previous studies have reported that presence and severity of Buruli ulcer (BU) may reflect the underlying immunosuppression in HIV infected individuals by causing increased incidence of multiple, larger and ulcerated lesions. We report cases of BU-HIV coinfection and the accompanying programmatic challenges encountered in central Ghana. METHODS: Patients with PCR confirmed BU in central Ghana who were HIV positive were identified and their BU01 forms were retrieved and reviewed in further detail. A combined 16S rRNA reverse transcriptase / IS2404 qPCR assay was used to assess the Mycobacterium ulcerans load. The characteristics of coinfected patients (BU+HIV+) were compared with a group of matched controls. RESULTS: The prevalence of HIV in this BU cohort was 2.4% (compared to national HIV prevalence of 1.7%). Eight of 9 BU+HIV+ patients had a single lesion and ulcers were the most common lesion type. The lesions presented were predominantly category II (5/9) followed by category I lesions. The median (IQR) time to healing was 14 (8-28) weeks in the BU+HIV+ compared to 28 (12-33) weeks in the control BU+HIV- group (p = 0.360). Only one BU+HIV+ developed a paradoxical reaction at week 16 but the lesion healed completely at week 20. The median bacterial load (16SrRNA) of BU+HIV+ patients was 750 copies /ml (95% CI 0-398,000) versus 500 copies/ml (95% CI 0-126,855,500) in BU+HIV- group. Similarly, the median count using the IS2404 assay was 500 copies/ml (95% CI 0-500) for BU+HIV+ patients versus 500 copies/ml (95% CI 500-31,000) for BU+HIV- patients. BU+HIV- patients mounted a significantly higher interferon-γ response compared to the BU+HIV+ co-infected patients with respective median (range) responses of [1687(81.11-4399) pg/ml] versus [137.5(4.436-1406) pg/ml, p = 0.03]. There were challenges with the integration of HIV and BU care in this cohort. CONCLUSION: The prevalence of HIV in the BU+ infected population was not significantly increased when compared to the prevalence of HIV in the general population. There was no clear relationship between BU lesion severity and HIV viral load or CD4 counts. Efforts should be made to encourage the integration of care of patients with BU-HIV coinfection