Sensory evaluation: The last hurdle in varietal development of yams (Dioscorea rotundata, poir) in Ghana

In variety development, sensory evaluation is not only the most important hurdle after all the necessary agronomic characteristics have been developed but also a major determinant of acceptability of thevariety, as well as a major determinant in the subsequent adoption and use of the variety. Eight yam genotypes out of thirty-six genotypes evaluated for yield, pest and disease tolerance and stability over athree year period, plus 3 farmers’ checks were assessed on parameters such as enzymatic oxidation, colour attractiveness, aroma, taste, texture and overall acceptability in relation to farmers’ checks (Dente,Brass and Dorban). Gender differences existed in the degree of perception of texture and taste of yams. KUP__2000/001 was the overall best genotype with respect to general acceptability in all agroecologiesfollowed by TDr_89/02665, 2000/001, TDr__ 89/02660, TDr__95/19177, Dente, Brass, Dorban, TDr__95/01932, TDr__95/01544 and TDr__98/02877 in that order. The results of this study indicated that accessions KUP_2000/001, TDr_89/02665 and 2000/001 were the most preferred accessions with respect to sensory evaluation. After clearing this all important hurdle of sensory evaluation, genotypes KUP_2000/001, TDr_89/02665 and 2000/001 were release as varieties CRIPona, MankrongPona and CRIKukrupa respectively in 2005

Petrography and Geochemistry of some Granitoids associated with Gold Mineralisation at Mpohor area in southeastern Ashanti Belt of the Birimian, Ghana

Mpohor area in Western Region of Ghana is located within the Birimian at the southeastern corridor of Ashanti belt. Diamond drilling in the area which encloses Father Brown concession intersected steeply dipping igneous rocks on which petrographic and whole rock XRF analyses were conducted to describe the rock types according to mineralogy, texture, alteration and mode of mineralisation. The study showed that gabbro and diorite are weakly deformed, partially altered and of greenschist facies metamorphism. These rocks intruded into belt granitoids which accompanied metavolcanic rocks (well exposed at a coastal region to the southeast). Subsequent tonalite and granodiorite intrusives into sheared areas of gabbro are deformed with foliation being parallel to the major foliation in the host rock. This ductile deformation was accompanied by brittle deformation and infiltrated by hydrothermal fluids leading to silicification, carbonatisation, sericitisation, pyritisation of second and third generations and gold mineralisation. On the contrary, chloritisation with fine chalcopyrite together with pyrite of first generation characterise host gabbro and diorite. Hence deformed pyrite porphyroblast of second generation is found in tonalite and partly in contact with magnetite and also associated with gold. The ore zone (Au grade between 1.78 to 48.80 g/t) in tonalite is characterised with lower TiO2 content (<0.73 wt %) in addition to Fe/Mg ratio above 2.4 and Zr values less than 100 ppm which may suggest that mineralised fluid was depleted of Ti and Zr and Mg/Fe ratio above 2.4. These probably show that hydrothermal fluid which has the potential for high sulphide-Au mineralisation accompanied more mafic host rocks. Keywords: Petrography, Geochemistry, Granitoids, Gold Mineralisation, Southeastern Ashanti bel

Ridging, a Mechanized Alternative to Mounding for Yam and Cassava Production

A cassava seedbed preparation field study was established at Fumesua in the forest and Ejura in the forest-savanna transition agroecologies of Ghana in 2004/2005. The experimental design was split plot with three seed bed preparation methods as the main plots and three nitrogen rates as sub plots, with basal application of 45-90 kg ha-1 P205 - K20 on the fertilized plots. A similar study was conducted on yam seedbed preparation in 2003/2004, with a 23 factorial design. Cassava and yams on ridges resulted in highest root and tuber yields, on both Lixisols in the coastal and forest-savanna transition and Acrisols in the forest agro-ecologies. However, yam tuber yield on mounds was not statistically different from yields on ridges. Number of roots per plant was identified as a major contributory factor to the yield increase of cassava on ridges. Seed bed preparation method was, however, not an important determinant of cassava root yield at high rates of fertilizer application of 90-45-90 kg ha-1 N-P205-K20. Planting on mounds resulted in slender, cylindrically shaped cassava roots and yam tubers, while ridging produced oblong shaped roots and tubers. Weeding and fertilizer application were easier on manual ridging than on manual mounds. The study points to ridging as a potential option to mounding for cassava and yam production, with the feasibility of mechanization of ridges to reduce drudgery associated with roots and tuber crop production in the West African sub-region

Identification of a Hemolysis Threshold That Increases Plasma and Serum Zinc Concentration.

Background: Plasma or serum zinc concentration (PZC or SZC) is the primary measure of zinc status, but accurate sampling requires controlling for hemolysis to prevent leakage of zinc from erythrocytes. It is not established how much hemolysis can occur without changing PZC/SZC concentrations.Objective: This study determines a guideline for the level of hemolysis that can significantly elevate PZC/SZC.Methods: The effect of hemolysis on PZC/SZC was estimated by using standard hematologic variables and mineral content. The calculated hemolysis threshold was then compared with results from an in vitro study and a population survey. Hemolysis was assessed by hemoglobin and iron concentrations, direct spectrophotometry, and visual assessment of the plasma or serum. Zinc and iron concentrations were determined by inductively coupled plasma spectrometry.Results: A 5% increase in PZC/SZC was calculated to result from the lysis of 1.15% of the erythrocytes in whole blood, corresponding to ∼1 g hemoglobin/L added into the plasma or serum. Similarly, the addition of simulated hemolysate to control plasma in vitro caused a 5% increase in PZC when hemoglobin concentrations reached 1.18 ± 0.10 g/L. In addition, serum samples from a population nutritional survey were scored for hemolysis and analyzed for changes in SZC; samples with hemolysis in the range of 1-2.5 g hemoglobin/L showed an estimated increase in SZC of 6% compared with nonhemolyzed samples. Each approach indicated that a 5% increase in PZC/SZC occurs at ∼1 g hemoglobin/L in plasma or serum. This concentration of hemoglobin can be readily identified directly by chemical hemoglobin assays or indirectly by direct spectrophotometry or matching to a color scale.Conclusions: A threshold of 1 g hemoglobin/L is recommended for PZC/SZC measurements to avoid increases in zinc caused by hemolysis. The use of this threshold may improve zinc assessment for monitoring zinc status and nutritional interventions

Sensory evaluation: the last hurdle in varietal development of yams (Dioscorea rotundata, poir) in Ghana

Open Access JournalIn variety development, sensory evaluation is not only the most important hurdle after all the necessary agronomic characteristics have been developed but also a major determinant of acceptability of the variety, as well as a major determinant in the subsequent adoption and use of the variety. Eight yam genotypes out of thirty-six genotypes evaluated for yield, pest and disease tolerance and stability over a three year period, plus 3 farmers’ checks were assessed on parameters such as enzymatic oxidation, colour attractiveness, aroma, taste, texture and overall acceptability in relation to farmers’ checks (Dente, Brass and Dorban). Gender differences existed in the degree of perception of texture and taste of yams. KUP__2000/001 was the overall best genotype with respect to general acceptability in all agroecologies followed by TDr_89/02665, 2000/001, TDr__ 89/02660, TDr__95/19177, Dente, Brass, Dorban, TDr__95/01932, TDr__95/01544 and TDr__98/02877 in that order. The results of this study indicated that accessions KUP_2000/001, TDr_89/02665 and 2000/001 were the most preferred accessions with respect to sensory evaluation. After clearing this all important hurdle of sensory evaluation, genotypes KUP_2000/001, TDr_89/02665 and 2000/001 were release as varieties CRIPona, MankrongPona and CRIKukrupa respectively in 2005

Evaluating inland valley agro-ecosystems in Ghana using a multi-scale characterization approach

As part of measures for improving the productive capacities of inland valley systems for rice-based cropping systems, a published multi-scale characterization approach was used in Ghana to assess the constraints and variables which must be understood before agronomic interventions are made. Macro, reconnaissance, semidetailed and detailed levels of characterization at their respective scales were used. Between 1996 and 1999, Geographical Information System (GIS) and transect studies were carried out, after which the extent of variability in the biotic and abiotic characteristics of two agro-ecologies were identified. Ten agro-ecological units were identified for Ghana based on map overlays and cluster analysis. The method allowed for the selection of Mankran and Jolo-Kwaha watersheds representing the equatorial and savanna agro-ecologies, respectively. Socio-economic parameters (markets, population density and suchlike) were recognized as the essential variables, which should be considered alongside lithology, climate, hydrology and others, for the choice of valleys for development interventions for crop production. At the detailed level of characterization, hydrological and soil characteristics underscored the need to properly understand the watershed-level and valleyspecific constraints before meaningful rice-based research and cropping systems are developed.En tant que partie de mesures pour améliorer les capacités productives de systémes de vallée de l\'intérieur pour les systèmes de culture basés sur le riz, une approche de caractérisation multiéchelle publiée était employée au Ghana en vue d\'estimer les contraintes et les variables qu\'il faut comprendre avant que les interventions agronomiques soient faites. Les niveaux macro, reconnaissance, semi-détaillé et détaillé de caractérisation à leurs échelles respectives étaient utilisés. Entre 1996 et 1999, l\'étude transversale et du Système Informationnel Géographique (SIG) étaient faites à la suite de quelle l\'étendue de variabilité de caractéristiques biotiques et abiotiques de deux agro-écologies étaient identifiées. Dix unités agro-écologiques étaient identifiées pour le Ghana basé sur l\'analyse de revêtements et de rassemblement sur la carte. La méthode permettait la sélection de lignes de partage des eaux de Mankran et de Jolo-Kwaha représentant respectivement les agroécologies équatoriales et savanes. Les paramètres socioéconomiques (les marchés, la densité de population, etc.) étaient reconnus comme les variables essentielles, qui devraient être considéré à côté de la lithologie, le climat, la hydrologie, etc.; pour le choix de vallées pour les interventions de développement pour la production des cultures. Au niveau détaillé de caractérisation, les caractéristiques de hydrologie et de sol soulignent la nécessité de comprendre vraiment les contraintes de niveaux de lignes de partage des eaux et les contraintes spécifiques à certaines vallées avant que la recherche et les systèmes de culture utiles basés sur le riz soient développés. Ghana Journal of Agricultural Science Vol. 40 (2) 2008: pp. 141-15

ACCELERATING DECOMPOSITION RATE OF FRESH FAECAL MATERIALS FROM A FARROW-TO-FINISH SWINE FARM WITH BLACK SOLDIER FLY LARVAE (Hermetia illucens)

There is need to generate  information required for the development of facilities for reducing  environmental pollution caused by careless dumping of raw faecal materials from swine production facilities into streams, channels, ponds and other water bodies in developing countries. The objectives of this work were to:(1) use a simple bio-decomposer to study the decomposition rate and waste reduction index (or efficiency of decomposition) of fresh solid  faecal materials obtained from a farrow- to- finish swine production unit when treated with Black Soldier Fly Larvae (BSFL) (2)  fit a regression curve with acceptable R-squared value to the  decomposition rate data generated in the study. With the use of the bio-decomposer, four batches of the Black Soldier Fly Larvae (BSFL) that developed from the hatched eggs were carefully collected and decanted from the faecal materials, after which they were weighed and mixed with four weighed samples of fresh solid swine faecal materials with three replications at an average inclusion rate of 94.3, 81.4, 61.4, and 59.04 gm of BSFL/kg of fresh solid swine faecal materials respectively in a Complete Randomized Design; the fifth sample of fresh solid faecal materials was used as the control. The average decomposition rates for the four samples treated at three treatment levels and control were 0.046, 0.041, 0.040, 0.040 and 0.0 kg/day, respectively translating to an average of 0.042 kg/day. These results depict a mean waste reduction index of 8.74 %/day indicating that high waste reduction efficiency has been obtained as attested to by the computed R-Squared value of   0.919. The fitted regression curve showed that the decomposition rate increased with increase in BSFL inclusion rate up to maximum limit of 42.85 g/day and inclusion rate of 63.27 g/kg for a 0.8 kg initial mass of fresh swine faecal materials. It was, therefore, concluded in the study that incorporation of BSFL is very effective for accelerated decomposition of fresh solid swine faecal materials from a farrow-to-finish production facility.     &nbsp

Linking Female Adolescents’ Knowledge, Attitudes and Use of Contraceptives to Adolescent Pregnancy in Ghana: A Baseline Data for Developing Sexuality Education Programmes

(1) Background: Nearly one out of ten Ghanaian female adolescents aged 15–19 has experienced childbearing in urban settlements compared to twice this number in the rural populations due to unintended pregnancies. This study assessed the linkages between knowledge, attitudes, and use of contraceptives and adolescent pregnancy in one of the highly affected Municipalities (i.e., Komenda-Edina-Eguafo Abrem [KEEA]) in Ghana. (2) Methods: Employing a facility-based sampling method, 378 female adolescents aged 15–19 were selected. Unadjusted odds ratio (uOR) and adjusted odds ratio (aOR) at 95% confidence intervals (CI) and p-values were used for significant variables at p < 0.05. (3) Results: Pregnant adolescents were 2 times more likely to indicate that the procedure of procuring contraceptives is quite uncomfortable (aOR = 2.42, 95% CI = [1.29–4.55]; p = 0.006). Also, pregnant adolescents were 5 times more likely to have ever used traditional contraceptive methods than their non-pregnant counterparts (aOR = 5.02, 95% CI = [2.60–9.71]; p < 0.001). On the contrary, pregnant adolescents had lower odds of indicating that contraceptives are for only married people (aOR = 0.38, 95% CI = [0.20–0.70]; p = 0.002) and that it feels bad to receive contraceptive information from parents and relatives than non-pregnant adolescents (aOR = 0.42, 95% CI = [0.24–0.74]; p = 0.003). Pregnant adolescents were less likely to use modern contraceptives than their non-pregnant adolescents (aOR = 0.18, 95% CI = [0.11–0.31]; p < 0.001). (4) Conclusions: The findings indicate that female adolescents’ use of traditional contraceptives is associated with the risk of pregnancy in KEEA Municipality within the Central Region of Ghana. However, adolescents who had the perception that contraceptives are for married people and those who used modern contraceptives were less likely to get pregnant. Government and non-governmental organizations in Ghana should implement educational policies and programmes aimed at educating sexually-active female adolescents on modern contraceptives and the need to use them to prevent pregnancies. The basis for such policies and programmes should be based on evidence that compared to traditional contraceptives, modern contraceptives are more effective. In addition, there is the need to provide accurate information regarding the use of contraceptives to adolescents that will help change their attitudes towards the use of contraceptives

Yam improvement for income and food security in West Africa: Effectiveness of a multi-disciplinary and multi-institutional team-work

The overall goal of the five year project “Yam Improvement for Income and Food Security in West Africa” (YIIFSWA) funded by the Bill and Melinda Gates Foundation and led by the International Institute of Tropical Agriculture, Ibadan, Nigeria was to: (a) increase yam productivity by 40% for 2,00,000 smallholder yam farmers in Ghana and Nigeria and (b) deliver key global good research products that will contribute to the 10-year overall vision to sustainably double incomes from yams for 3 million smallholder yam farming families and contribute to ensuring food security for producers and consumers. Implemented by scientists of twenty partner specialized organizations, comprising research institutes, Universities, governmental and non-governmental organizations, YIIFSWA has impacted yam value chain stakeholders through research and development interventions. The significant contributions made in the project during the past 18 months’ period are discussed in this paper. These include: a baseline survey conducted in key yam growing areas in Ghana and Nigeria, training of yam producers on adapted yam minisett technique and production of seed yam, undertaking in depth value chain assessments, developing the capacity of Farmers Organizations (FOs) by linking them to service providers (SPs), participatory evaluation of new yam genotypes, successful development of yam virus diseases diagnostics and development of novel techniques for high ratio yam propagation such as aeroponics and bioreactors

Resistance screening of white yam (Dioscorea rotundata Poir.) accessions against Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949 using yam vines

Open Access Article; Published online: 05 Apr 2022Root-knot nematode (Meloidogyne incognita) is an economically important phytoparasitic nematode species. In yam production, therefore, breeding for nematode resistance is an important environmentally friendly tool to manage root-knot nematodes damage. The aim of this study was to determine the reaction of 18 yam accessions to M. incognita inoculation under screen house conditions using single node vine cuttings. Vines of each accession were planted in sterilized soil and inoculated with 1000 infective juveniles of M. incognita. Resistance level of yam accessions were based on both galling index score and reproductive factor. There were a significant differences in final infective stage nematodes population, galling index, reproduction factor and yield of mini tuber among the accessions tested. Sixteen (89 %) of the accessions showed moderate resistance (GI ≥ 2, Rf ≤ 1) to the test pathogen with two accessions classified as susceptible. Accession TDr1515OP16/0030 recorded the highest mini tuber yield mass of 19.4 g, which was 74 % higher than accession ‘TDr1515OP16/0108’ which recorded the lowest yield of 10.4 g. The moderately resistant accessions identified in the study can be utilized to reduce nematodes reproduction and help manage root-knot nematode in yam production