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Item On Farm And Post-Harvest Management Of Mango Stone Weevil (Sternochetus mangiferae F.)(University Of Ghana, 2022-05) Aboagye, E.N.G.A questionnaire composed of twenty-three (23) open and closed-ended questions was administered to thirty (30) mango farmers within the eastern mango enclave to investigate the level of mango stone weevil (MSW) infestation within the eastern mango enclave. Data obtained from the questionnaire was analysed using the SPSS version 25.0 and presented as tables in percentages. Chi-square was used to determine the association between selected parameters. The response from farmers revealed that 40.7% of farmers grow only one variety of mango and the common variety is Keitt which is cultivated by 33.7% of the farmers. About eighty-seven percent of the farmers admitted to the presence of the mango stone weevil on their farms. Fifty percent of the farmers were found to be relying on insecticides for controlling the MSW. About seventy-seven percent of the respondents viewed the mango stone weevil as a major pest because it is a pest of phytosanitary importance. The major mango season was considered to have the highest infestation as indicated by 90% of respondents. Responses from farmers revealed that 76.7% spend about GH¢2000:00 – 5000:00 per acre every season in controlling the mango stone weevil. A survey was conducted during the major and minor mango seasons immediately after the questionnaire administration. During the survey, thirty (30) farms were visited. On each farm, fifty (50) matured fruits were randomly picked and dissected to check whether the seeds are infested or free from weevils. The survey brought to light that, the MSW is at its highest level during the major season as compared to the minor season. Infestation levels on the average were 23.6% and 19.13% for the major and minor seasons respectively. To determine the effect of trunk banding using a sticky band, grease and insecticide in the control of MSW, the sticky band proved to be the most efficient method. The sticky band had lower fruit infestation levels (i.e., 11.5% for minor mango season and 10.5% for the major mango season) which were significantly different from the fruit infestation levels of the grease banding for both minor and major seasons. Although an X-ray imaging technique could not capture the image of mango stone weevil within infested fruits, it was able to capture the image of damaged cotyledon which resulted from feeding by mango stone weevils. The findings of the research showed that the mango stone weevil is persistent in the study area, mango stone weevil infestation levels are high during the major mango season, the sticky band is more effective in controlling the mango stone weevil and lastly soft X-ray technique can be used to detect internal infestation of mango by the stone weevil. These findings would go a long way to address the menace of MSW infestation, the efficient and effective method of controlling mango stone weevil and a non-destructive method of detecting MSW infestations which would improve the fortunes of Ghana in the export of fresh mango fruits.Item Effect Of Gamma Irradiation On Propagation And Creation Of Variability In Caesalpinia Pulcherrima L And Canna Indica L(University Of Ghana, 2022-10) Owusu, E.Item Mutagenesis Of Cowpea for Early Maturity and Higher Yield(University of Ghana, 2020-10) Dorvlo, I.KABSTRACT Cowpea [Vigna unguiculata (L.) Walp.] is an important grain legume that is widely grown in sub-Saharan Africa (SSA) for food and feed. Its grain is composed of high levels of protein, carbohydrate, micro-nutrients and macro-nutrients which are essential for human nutrition. In Ghana, cowpea productivity is considerably low due to frequent terminal drought as a result of climatic changes. Therefore, breeding improved varieties by incorporating “farmer-preferred” traits remains an overriding consideration to boost the productivity of cowpea in Ghana. The main objective of this study was to develop early maturing and high seed yielding cowpea varieties through mutation induction using gamma irradiation. Before the commencement of the mutagenesis, it is important to determine the right dose of gamma radiation for causing genetic variability in the desired agro-economic trait. Therefore, seeds of a farmer-preferred cowpea variety ‘Videza’ (obtained from a farmer in Akatsi, Volta region of Ghana) were gamma irradiated using twelve irradiation doses (0, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000 and1100 Gy) at GAEC. Using a linear regression model, the LD50 value of the cowpea variety ‘Videza’ was calculated as 240.51Gy. A dose-dependent reduction was observed in seed germinastion, seedling survival and plant height. For mutation induction, 2000 seeds of cowpea variety ‘Videza’ were acutely irradiated at 230 Gy, at the Radiation Technology Centre (RTC) of Ghana Atomic Energy Commission (GAEC), Accra, Ghana, using a Cobalt 60 source, delivering at a dose rate of 300 Gy/hr. Normal looking M1 plants with the desired traits (early maturity and high seed yield) were advanced to M2 generation and further advanced to M3 generation. The planting was linear and serpentine at a seeding rate of one seed per hill using 75cm x 40 cm. Control seeds were sown in three rows after every ten rows of the irradiated seeds separated by a spacing of 1.50m. Compared to the Control (Videza), genetic variability was recorded among plants in both M2 and M3 generation. The extent of genetic variability for the number of days to 50% flowering, number of days to 90% maturity, number of pod-bearing branches per plant, number of pods per plant, number of seeds per pod, 100-seed weight (g) and seed yield per plant (g) were evaluated in M2 and M3 generations. The number of days to 50% flowering and 90% maturity reduced in putative mutants in both M2 and M3 generations compared to the parental line (Control). The number of days to 50% flowering and days to 90% maturity, reduced further in the M3 generation as compared to M2. Increments in 100-seed weight per plant (g) and seed yield per plant (g) were observed among the putative mutants in M3 generation compared to the parental line (Control). The following twelve putative mutant lines P1N06#20, P1N06#9, P1N08#13, P1N08#17, P2N09#12, P4N03#2, P4N14#7, P5N05#10, P5N07#14 and P6N10#19 were outstanding in the M3 generation, exhibiting both early maturity as well as high seed yield. The twelve putative mutant lines are recommended for yield trials (preliminary and advanced), alongside the parental line (Videza) as well as a local check (as Controls), in farmer-participatory multilocational trials (including the Akatsi District of the Volta Region of Ghana) towards identifying superior lines for release as new variety or varieties.Item Biopesticide Control of Some Important Okra (Abelmoschus Esculentus (L.) Moench) Insect-Pests and Viral Diseases in Three Okra Cultivars(University of Ghana, 2020-10) Akama, C.K.A.The production, processing and marketing of Okra (Abelmoschus esculentus L. Moench), a vegetable valued for its rich nutritional and medicinal benefits, serves as an important means of employment and income generation to many peasant farmers. The production of the crop is, however, constrained by the incidence of pests (whitefly and flea beetle) and okra yellow vein mosaic virus [OYMV] and okra mosaic virus [OMV]) diseases. To overcome the health and environmental risks associated with the excessive use of synthetic agrochemicals, the predominant means of control of these pests and viral diseases, the efficacy of crude leaf extracts as biopesticides from Neem, Jathropha and Lemon grass on the incidence and severity of OMV and OYVMV as well as crop damage due to whitefly and flea beetle, were evaluated in three okra cultivars [F1 Kirene (F1K), FI Sahari (F1S) and Asontem (AST)]. Among the three plant extracts tested, Neem extract treatment induced significantly (p<0.05) the lowest mean count of whitefly [ASTNEM (18.91), F1KNEM (22.17), F1SNEM (24.49)] compared to Jathropha extracts [ASTJAT (27.99), F1KJAT (28.73), F1SJAT (28.74)] and Lemon grass extract treatments [ASTLEM (34.22), F1KLEM (32.77), F1SLEM (32.67)]. Similar results were obtained for mean population of flea beetle. With respect to insect pests damage to the okra cultivars, Neem extract caused significantly (p<0.05) the lowest severity of damage [F1KNEM (1.53), F1SNEM (1.58), ASTNEM (1.63)] compared to Jathropha extract treatment [F1SJAT (2.74), ASTJAT (2.75), F1KJAT (2.77)] and Lemon grass extract [F1SLEM (2.97), ASTLEM (3.64), F1KLEM (3.73)]. Similarly, the application of Neem extract significantly (p<0.05) reduced the mean incidence (21.84%) of the viral diseases than Lemon grass extract (25.28%), Jathropha extract (25.44%) and the Control (28.89%). In-vitro confirmation test using Enzyme-linked immunosorbent assay (ELISA) revealed that majority (86.67%) of the treatment combinations showed single infection of OMV disease while in 13.33% of the treatment combinations mixed-infection of OMV and OYVMV diseases was observed. In terms of yield levels, chemical pesticide treatment produced significantly (p<0.05) highest yield (186.92 kg/ha) compared to Neem extract treatment (144.81 kg/ha), Jathropha extract (139.06 kg/ha), Lemon grass extract (115.75 kg/ha) and the Control (94.02 kg/ha). However, Neem extract performed best among the tested plant extracts. Therefore, in a second experimental trial to ascertain the best efficacious dose for Neem extract application, varying concentrations of 20 ml/L, 30 ml/L and 40 ml/L were used and compared with the chemical “Akape” in the three okra cultivars (F1K, F1S and AST) instead of the 50ml/L applied in the first experimental trial. Treatment with “Akape” recorded significantly (p<0.05) the lowest mean whitefly populations than treatment with plant extracts. However, 20 ml/L Neem extract treatment produced significantly (p<0.05) lowest mean count of whitefly [F1KN1 (17.88), ASTN1 (23.95), F1SN1 (29.01)] compared to 40 ml/L Neem extract [F1KN3 (37.90), ASTN3 (39.57), F1SN3 (38.22)]. Similarly, although the application of the synthetic chemical (insecticide) “Akape” resulted in the best performance in reducing flea beetle populations, it was observed among the Neem extract concentrations, 20 ml/L treatment produced significantly (p < 0.05) lowest flea beetle mean count [F1KN1 (24.04), ASTN1 (25.61), F1SN1 (29.41)] compared to 30 ml/L [F1KN2 (49.89), ASTN2 (48.73), F1SN2 (51.92)] and 40 ml/L [F1KN3 (72.68), ASTN3 (65.88), F1SN3 (80.88)] treated okra cultivars. Okra cultivars treated with 20 ml/L Neem extract had significantly (p<0.05) lowest severity of insect pest damage compared to treatment with 40 ml/L Neem extract. Of the three concentrations of Neem extract applied, 20 ml/L (N1) significantly (p<0.05) reduced severity of mixed-infection of OMV and OYVMV) in all the three okra cultivars [ASTN1 (0.64), F1KN1 (0.84), F1SN1 (1.23)]. Yield of okra cultivars treated with chemical pesticide was significantly (p>0.05) highest (234kg/ha). However, yield obtained with 20 ml/L Neem extract treatment (207kg/ha) was significantly (p>0.05) highest compared to the other Neem extract doses. It is noteworthy that cultivar F1 Kirene recorded significant (p<0.05) the highest yield (207kg/ha) followed by F1 Sahari (139kg/ha) and Asontem (127kg/ha). From the obtained results, the cultivation of the okra cultivar F1 Kirene could be combined with Neem extract at a concentration of 20 ml/L to obtain effective disease and pests control for high yields.Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Ofosu, D. O.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the effect of gamma irradiation and packaging on the physico-chemical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory evaluation were administered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorula). The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, A. flavus, A. fum igat us, A. niger, A. sulphureus, A. ustus) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to 10kGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticilloides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Ofosu, D.O.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the e ffect 0 f gamma irrad iation and packaging on the phys ico-chem ical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory eval uation were adrn inistered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorulai. The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, /I. flavus, A. fum igat us, A. niger, A. sulphureus, A. us/us) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to IOkGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticil/oides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Nodulation, Nitrogen Fixation and Biomass Yield of Selected Forage Legume Species in Coastal Savannah Zone of Ghana(University of Ghana, 2017-07) Dien, M.K.Two field experiments were carried out in the major and minor rainy seasons at the BNARI research farm at Kwabenya, Accra, Ghana from July – November, 2016 to investigate nodulation, biomass yield and nitrogen fixation potential of ten forage legumes (Macroptilium atropurpureum, Stylosanthes guianensis, Crotalaria ochroleuca, Pueraria phaseoloides, Centrosema pubescens, Calopogonuim mucunoides, Cajanus cajan, Flemingia macrophylla, Lablab purpurus and Desmodium distortum). Completely randomized block design (RCBD) with four replications of each of the above named forage legumes was used. Sampling was done at eight weeks after planting for all the legume plants for both major and minor rainy seasons. Sub – samples of both maize and legume species for both major and minor rainy seasons were oven dried at 65oc for 72hrs, milled to fine powder and per cent total N analyzed using Kjeldahl Digestion Method at ECO LAB, University of Ghana, Legon. Nitrogen content for each sample was calculated using the per cent N analyzed and nitrogen difference method used in determining the N-fixed by the legume species. Nodules harvested from sampled plants were washed, moped, weighed for both fresh and dry nodule weight, counted for nodule number and sliced for nodule effectiveness for both major and minor rainy seasons. Data collected was subjected to analysis of variance (ANOVA) of RCBD using GENSTAT statistical package version 16 edition and Duncan’s Multiple Range Test (DMRT) used to separate means where significant differences were observed. On the whole, Crotalaria ochroleuca, C. cajan, L. purpureus, D. distortum and M. atropurpureum produced high dry matter yields. However, the highest (6817kg ha-1) and lowest (1747 kg ha-1) mean shoot dry matter yield for the major rainy season was produced by L. purpureus and S. guianensis respectively. The highest mean dry matter yield for the minor rainy season was 255.30 kg ha-1 for C. ochroleuca while the lowest was 110.30 kg ha-1 for C. pubescens. The highest mean total N yield being 144.50 kg N ha-1 was produced by L. purpureus and 47.70 kg N ha-1 being the lowest value was obtained by S. guianensis during the major rainy season. Crotalaria ochroleuca produced the highest N yield with the value 77.96 kg N ha-1 while the lowest N yield of 38.37 kg N ha-1 was produced by C. pubescens during the minor rainy season. The highest and lowest mean number of nodules produced per plant for the major rainy season were 266.50 for C. cajan and 16.5 for C. mucunoides respectively while the highest and lowest mean number of nodules for the minor season were produced by L. purpureus (153.5) and C. pubescens (3.75) respectively. However, the highest and lowest mean effective number of nodules for the major rainy season were produced by C. cajan (238) and C. mucunoides (10) respectively while the highest and lowest values for the minor season were 139 and 2 for L. purpureus and C. pubescens respectively. Cajanus cajan had the highest mean effective nodules (237.75) and F. macrophylla produced the lowest (10.25) effective nodules (EN) for the major season while in the minor season, L. purpureus had the highest EN (139) with C. pubescens having the lowest EN (3.75). The highest total nitrogen derived from atmosphere (Ndfa) for major rainy season was 112.45 kg N ha-1 for L. purpureus and the lowest total Ndfa of 15.64 kg N ha-1 was produced by S. guianensis. The legume species, C. ochroleuca had the highest Ndfa of 52.93 kg N ha-1 whiles C. pubescens produced the lowest Ndfa of 13.35 kg N ha-1 for the minor rainy season. Statistical analysis indicated highly significant (p ≤ 0.001) seasonal effect on most of the parameters measured for the forage legume species except root dry matter and N yields that had non- significant (p ≥ 0.05) seasonal effect. In conclusion, the linear regression between dry weight of effective nodules and Ndfa for each season, showed positive relationship with R2 values of 0.5807 and 0.4513 respectively, implying that increasing dry weight of effective nodules results in increasing NdfaItem Decomposition and Mineralization of Some Organic Residues in Two Contrasting Agro-Ecological Zones(University of Ghana, 2017-07) Tetteh, D.M.Decomposition and mineralization from plant and animal residues are important processes that can improve soil fertility and build–up soil organic matter. Decomposition and mineralization of 5 and 10 t/ha of matured cow dung (CD) in Ada soil series of the coastal savannah agro-ecological zone, as well as 5 and 10 t/ha of artisanal empty fruit bunch (EFB-AT) and industrial empty fruit bunch (EFB-IN) in Kokofu soil series of the semi-deciduous forest agro-ecological zone were studied using pots. The objective of the study was to assess the decomposition and nutrient release patterns of manured CD and EFB-AT and EFB-IN in order to give an estimate of the release patterns and to synchronize the nutrient release to meet the nutrient demands of crops. The study was conducted between February and June 2017. The dry CD at the two application rates were used for the study in Ada soil series, classified as Entisols (USDA classification) by Brammer (1960), which corresponds to Fluvisols under FAO (1970) classification. Also dry EFBs were used for the Kokofu soil series which are classified Ultisols USDA (Brammer, 1960). Dry CD was put in nylon litter bags, and was buried at 8 cm deep in the soil (in the pots) as practised by farmers in the Sege area, where CD is incorporated into the soil on application. Chopped EFBs of 2cm mesh size were put in nylon litter bags, and placed on the surface of soil in the pots as practised by farmers in the Kade area, where EFBs are placed on the soil surface in most oil palm plantations to serve as mulch. The EFB samples were taken from artisanal palm oil producers (EFB-AT) and industrial palm oil producers (EFB-IN). Buried CDs in pots were sampled at 7, 14, 21, 35, 56, 72 and 90 days whiles EFB-AT AND EFB-IN were sampled 7, 14, 21, 35, 56, 72 90,120 and 150 days after being placed on soil surface in pots. Sixty percent (60%) of the initial weight of the CD decomposed within 90 days with no significant difference (t=0.05) in the fractions lost between 5 and 10t/ha by t- test analysis, based on pair comparison. In the case of EFB-AT, about 20% of the 5 t/ha and 50% of 10 t/ha, of the initial weight had decomposed over the 150 days period. For EFB-IN about 78% of the 5 t/ha and 75% of the 10t/ha of the initial weight decomposed over the 150 days period. Comparatively, a t-test analysis, based on pair comparison, showed a significant difference (t=0.08) between the fractions lost by EFB-AT and EFB-IN at the two application levels. The estimated half-life (t ½) for the decomposition of CD were 82 and 99 days for 5 t/ha and 10 t/ha, respectively. For EFB-AT, the estimated half-life were 112 and 130 days for 5 and 10 t/ha, respectively, while for EFB/IN half-life was 83 and 87 days for 5 and 10 t/ha, respectively. Approximately between 10 and 20% of the initial TN content of the CD was released during the 90 days period with significant difference (t=0.07) in the fractions released between 5 and 10t/ha of CD. Similarly, approximately 15-20% of the initial TN of the EFB-AT and between 30 and 38 % of TN in EFB-IN was released during the 150 days period. Based on pair comparison, the difference in the TN released between EFB-AT and EFB-IN was significant (t=0.07) even between the two application rates (5 and10t/ha). Between 30-38% of the initial P content of the CDs was released while about 60% of the EFBs was released with significant difference (t=0.06) in the fractions released between 5 and 10t/ha, and between EFB-AT and EFB-IN. About 90% of the initial K content in EFBs was released while about 40-50% of the initial K content of the CDs was released during the experimental period, with significant difference (t=0.07) in the fractions of K released between 5 and 10t/ha CD and between EFB-AT and EFB-IN.Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Odamtten, G.T.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the e ffect 0 f gamma irrad iation and packaging on the phys ico-chem ical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory eval uation were adrn inistered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. XIV xv The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorulai. The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, /I. flavus, A. fum igat us, A. niger, A. sulphureus, A. us/us) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to IOkGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticil/oides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Studies Of Essential And Non-Essential Elements In Cereal-Based Weaning Foods For Infants Commercially Available On The Ghanaian Market(University of Ghana, 2013-07) Bawol, S.Cereal-based weaning foods, which abound on the Ghanaian market, are nutritionally vital in the growth and development of infants. Recent reports in scientific literature however indicate that rice and other cereals used in the manufacture of the weaning foods contribute significantly to the intake of arsenic (As), cadmium (Cd) and lead (Pb) by infants. In view of this, frequent monitoring of the cereal-based weaning foods has become imperative. The study assessed the beneficial health effects and risks posed by the consumption of cereal-based weaning foods commercially available on the Ghanaian market with respect to the essential elements (Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Se, V and Zn) and, non-essential, potentially toxic elements (As, Br, Hg, Pb and Sn). Twenty (20) different brands of weaning foods were purchased from various retail outlets in Accra and used for the study. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry [with flame atomisation (FAAS) and hydride generation (HGAAS)] were used in analysing the samples. Determination of Pb using FAAS was done following its extraction with dithizone. The analytical methods were validated using certified reference materials NIST 1568a (Rice flour) and NIST 1547 (Peach leaves). The levels (μg/g, in ranges) obtained for the elements were: As (< 0.025), Br (<0.17-402), Ca (405-2002), Cl (158-5521) and Cr (<0.03-1.23). Others are: Cu (0.83-55.80), Fe (1.07-11.78), Hg (< 0.025), K (49-3845) Mg (20-280) and Mn (0.84-38.94). The rest include: Na (13-1588), Pb (0.025-0.093), Se (0.145-0.317), Sn (35.8-91.8), V (<0.01-0.990) and Zn (0.50-7.17). The daily intakes of the essential elements were also estimated, and generally found to be lower than recommended values set either by the FAO/WHO, the European Food Safety Authority (EFSA), the US Food and Nutrition Board, or the Joint Societies for Nutrition of Germany, Austria and Switzerland. The estimated intake levels of the non-essential, potentially toxic elements As, Hg, Sn and Pb were all lower than their respective provisional tolerable weekly intake (PTWI) values established by the Joint FAO/WHO Expert Committee on Contaminants and Food Additives (JECFA). The results indicated that the analysed food samples were generally safe for consumption with respect to their content of the non-essential elements analysed. However, the contributions of the food samples to the daily essential element needs of the infant were mostly woefully inadequate, and this may not augur well for the proper growth and development of infants that consume them.Item Investigations Into The Shelf Life And Nutritional Quality Of Fresh Tomato Fruit (Solanum Lycopersicon) Following Two Post - Harvest Treatments(University of Ghana, 2013-07) Gyimah, L.A.Tomato production in Ghana is characterized by a glut and high post – harvest losses during the major season followed by scarcity and high prices during the off season. This is the result or absence of a standard method for preservation of fresh fruits. This research was conducted to determine an effective method for the post - harvest treatment of fresh tomato fruits to enhance shelf life while preserving its physicochemical and nutritional properties. Two experiments were conducted, each with a factorial design of 5x2. In experiment one, the fruits were subjected to 0, 1, 2, 3 and 4 kGy gamma radiation and stored at 10±1ºC and 28±1ºC. In experiment two, CaCl2 dissolved in distilled water at 0, 1.00, 1.50, 2.00 and 2.50 % concentrations were used to coat tomato fruits and stored at 10±1ºC and 28±1ºC. Gamma radiation at 4kGy extended the shelf life of tomato by 5 and 9 days above control when stored at 28±1ºC and 10±1ºC respectively. The use of CaCl2 at 2.50% greatly extended the shelf life of tomato by 11 days and 18 days above control when stored at 28±1ºC and 10±1ºC respectively. For both treatments, shelf life increased with increasing dose of radiation/ concentration of CaCl2. Weight loss was higher in control fruits as well as fruits treated with gamma radiation or CaCl2 coating stored at 28±1ºC temperature than treated fruits stored at 10±1ºC. Tomato fruits treated with gamma radiation at 1 and 2 kGy and untreated fruits showed an increase in pH and Total Soluble Solids (TSS) which was paralleled by a decrease in Total Titratable Acidity (TTA) as storage period advanced at both storage temperatures. However, fruits treated with CaCl2 at 1.00% had little effect on pH and TTA of tomato during the storage period. Nutritionally, CaCl2 coating significantly maintained the vitamin C and lycopene concentrations in tomato fruit more than control and gamma irradiation which reduced vitamin C and lycopene contents in the fruits significantly with days of storage. Storage at 10±1ºC better preserved the antioxidants properties of the fruits better than storage at 28±1ºC. Elemental composition (Na, K, Zn, Cu and Mn) of the tomato fruits analysed on the initial and final days of storage showed K to be the element with the highest concentration whilst Zn was the least. Generally, gamma irradiation led to an increase in the concentration of Na and K for all doses whilst CaCl2 coating significantly decreased the concentrations of the same elements at both storage temperatures. Concentrations of Zn, Cu and Mn reduced significantly in the tomato fruits by the final day of storage for all treatments following storage at 10±1ºC whilst there were inconsistencies in the contents of the elements in tomato fruits stored at 28±1ºC. Gamma radiation and CaCl2 significantly reduced the microbial load in tomato at both temperatures compared to the control. The reduction was proportional to increasing dose of irradiation and concentration of CaCl2. However, CaCl2 significantly reduced Total Aerobic Mesophiles as well as Mould and Yeast growth in tomato fruits compared to gamma irradiation at both temperatures. In general, treated tomato fruits stored at lower temperature (10±1ºC) had more stability and longer shelf life as well as the ability to maintain nutritional properties than those stored at 28±1ºC.Item Effect Of Npk Fertiliser On Growth, Flowering And Yield Of Fonio (Digitaria Exilis) In A Coastal Agro-Ecological Environment Of Ghana(University of Ghana, 2013-07) Amekli, Y.Fonio (Digitaria spp) is a neglected and underutilised crop traditionally grown in the Sahelian savannah agro-ecological zone of Ghana for its grain which is rich in crude protein, fibre and has medicinal properties. Decline in production of the crop is attributed to poor agronomic and yield characteristics and changing agro-climatic conditions as a result of global warming which has rendered traditional growing areas too dry to support cultivation of the crop. There is a need to explore the possibility of growing the crop in new agro-ecologies to sustain the production. The study was therefore conducted in Kwabenya-Atomic area which is located in the coastal savannah agro-ecological zone of Ghana, to evaluate the adaptability of three fonio landraces (Yadema, Nomber and Nvoni) to the coastal zone, their growth and response to NPK 15:15:15 fertiliser treatment, apparent fertiliser nitrogen recovery (AFNR) as well as presence of basic elements, in the grains. Field experiments were conducted in 2012 during the major cropping season, using three fonio landraces grown at a planting distance of 0.05 m 0.45 m. The experiment design used was the split plot in three replicates. Plants were sampled every two weeks throughout the growing season. Grain yield (GY) and its associated apparent fertiliser nitrogen recovery were significantly different (P ≤ 0.05) among the fonio landraces during the cropping season with the landrace Nvoni producing the highest grain yield of 964 kg ha−1 at NPK fertiliser rate of 60 kg ha−1 and with a AFNR of 33.1%. The study also established a positive correlation between biomass accumulation and grain yield. The efficiency of grain production per unit of fertiliser nitrogen (FN) increased, but at a diminishing rate with each additional unit of FN. Additionally, ten essential mineral elements (Na, Mg, K, Ca, I, Cl, Cu, Al, Mn and V) were detected among the grain of the three fonio landrace using Instrumental Neutron Activation Analysis (INAA).Item Development And Preservation Of A Cocktail Beverage Produced From Carrot (Daucus Carrota), Pineapple (Ananas Comosus) And Mango (Mangifera Indica L,)(University of Ghana, 2013-07) Boateng, A.A.Carrot is known to have the potential of providing vital nutrition as well as health and well-being to consumers. In this study, carrot juice was envisaged as a good vehicle for spreading its nutraceutical benefits. The study was then designed in two parts: (a) Survey to establish the beverage consumption pattern in the Anyaa-Sowutuom District in the Greater Accra Region of Ghana and (b) Carrot juice formulation and optimisation. The survey was conducted by administering a questionnaire to volunteer adult consumers. To develop an acceptable carrot juice beverage, pineapple juice and mango juice were included as components to improve taste and flavour respectively. A constrained, simplex centroid mixture design for three components was employed to optimise the proportions of the components in the final product based on sensory attributes. Chemical analyses as well as shelf stability studies were conducted for the optimised beverage preserved by chemicals and gamma radiation. Data obtained from the survey revealed that juices were very popular among consumers. The choice of a particular beverage was dependent on nutrition, taste and colour. Contour plots generated from sensory data of the products were overlaid to determine the optimum ratios of the components of the cocktail beverage. The optimised product consisted of 50-52 % Carrot, 18-20 % Pineapple and 28-30 % Mango. Analysis of the beverage revealed 223 mg/100ml Potassium, 3.92 mg/100ml Pro-vitamin A (Beta carotene) and 43 mg/100ml Vitamin C. After 8 weeks of storage 77 % Pro-vitamin A was retained in products chemically treated and as well as products irradiated at 1 kGy. However, about 60 % of this same nutrient was retained even under relatively higher dose (2.5 kGy) of gamma radiation. The microbial quality of the beverage was good under all conditions studied.Item Effect Of Irradiation On The Shelf Life And Nutritional Quality Of Tomato (Solanum Lycopersicon L.) Powder(University of Ghana, 2013-07) Atuobi-Yeboah, A.A.Tomato (Solanum lycopersicon L.) is a major horticultural crop with an estimated global production of over 153 million metric tons. It is the most important fruit vegetable and the second most widely cultivated crop in the world after potato, with a total production of about 141 million tons. In 2009, the average total yield in Ghana was 7.5 Mt ha-1 compared to the achievable yield of 15.0 Mt ha-1. The tomato industry in Ghana for the past decade has been bedevilled by a myriad of problems of which post-harvest losses range between 30% and 70% in the major seasons of production, hence a study was conducted into the preservation of S. lycopersicon L. through drying and packaging to reduce post-harvest losses. Two drying methods comprising of solar and freeze drying were employed for three varieties of tomato which are cultivated locally. The methods were compared to determine the more efficient for the three varieties used in the study and the impact of drying and radiation on some physico-chemical properties, microbial load as well as shelf-life of the samples. Evaluation of the packaging material for the dried samples was also carried out. The samples were exposed to gamma irradiation at 0 kGy, 1 kGy, 2 kGy and 3 kGy. The parameters determined included moisture content, pH, titratable acidity; total soluble solids total carotenoids, lycopene, lutein and beta carotene. Microbial analysis carried out included total aerobic mesophilic bacteria count, total coliform count and moulds and yeasts using standard methods. Data were analyzed using ANOVA. Storage had significant effect (p<0.05) on the pH, TSS, TTA, colour and microbial load of the various varieties used. Irradiation had a significant effect (p<0.05) on pH, colour, microbial quality, lycopene content, beta carotene, and total carotenoid content of the varieties used; however irradiation had no significant (p>0.05) effect on moisture content, total soluble solids and microbial quality of the varieties used. Comparing powders obtained from freeze dried and solar dried tomatoes (Akoma), solar drying emerged as a more efficient method of drying. In Akoma, significant differences (p<0.05) were observed in all the parameters due to the difference in drying methods. Gamma irradiation did not affect (p>0.05) the moisture content, total soluble solids, of the Akoma variety irrespective of the drying method used. However, gamma irradiation had a significant effect (p<0.05) effect on pH, colour, total aerobic mesophilic counts, total coliforms; moulds and yeast, total carotenoid, lutein and beta carotene. Storage had significant (p<0.05) effect on the colour, total carotenoid content, and lycopene of the powders from the two drying methods. The packaging material used was suitable for the solar dried powder but not the freeze dried powder. Varietal differences (p<0.05) existed between the tomatoes in terms of moisture content, total soluble solids, pH, titratable acidity, colour, total aerobic mesophilic counts, total coliform count and total moulds and yeast counts.Item Effect Of Irradiation And Colchicine On Callus And Somatic Embryo Formation In Cassava (Manihot Esculenta Crantz)(University of Ghana, 2012-06) Dzimegah, D.A.A study was conducted to assess the mutagenic effect of gamma radiation on sprouting and height in four local cassava accessions.The four cassava accessions were assessed for their callus induction and somatic embryo formation ability from leaf lobes from gamma irradiated stakes as well as colchicine treated leaf lobes on different concentrations of plant growth regulators, incorporated into Murashige and Skoog, (1962) (MS) basal medium. The cassava accessions were irradiated at 0, 32, 35, 45 and 50 Gy and planted in pots filled with loamy soil. The height of the shoots was measured with rule after sprouting. The leaf lobes were collected from the shoots and cultured on MS medium supplemented with 8 mg/l 2,4-D and 16 mg/l Picloram. Another set of leaf lobes were treated with 0.0, 0.05, 0.1, 0.2, 0.25 g/l colchicine for one hour and thereafter cultured on MS medium supplemented with 8 mg/l 2,4-D and 16 mg/l Picloram as described above. Callus induction from leaf lobes in 45 and 50 Gy were significantly (p≤0.05) affected by the irradiation. However, callus induced from leaf lobes in 32 and 35 Gy were not significantly (p≤0.05) affected by the irradiation. On the other hand, Callus induction from leaf lobes in 0.1-0.25 g/l colchicine were significantly (p≤0.05) affected by the mutagenic treatment whereas callus induced from leaf lobes in 0.05 g/l colchicine was not significantly (p≤0.05) affected. Callus induced on 8 mg/l 2,4-D and 16 mg/l picloram gave the best response in Ankrah and all control tested while Tomfa recorded the least. Colchicine at a concentration of 0.05 g/l and radiation dose of 32 Gy treatments gave the best response of callusing. Callus induction decreased with increasing colchicine concentration and gamma irradiation. Callus derived from irradiated and colchicine leaf lobes appeared soft but friable and tiny, compact, respectively, predominately with creamy to brown colouration.Calli obtained were sub-cultured on embryo regeneration medium consisting of MS supplemented with 0.01mg/l NAA and 0.1 mg/l BAP. There was no plantlet regeneration. Instead, embryo formation and prolific root was observed in cases where there was no embryo. Similarly, somatic embryo formation was significantly (p≤0.05) different among the accessions. No response to callus formation was observed in 0.25 g/l colchicine treatment after 30 days. Among the four accessions evaluated, Ankrah was the most promising accession in terms of callus induction frequency and somatic embryo formation ability. The results presented in this thesis clearly show that, sprouting in all accessions decreased as the dose of irradiation increased. Gamma irradiation had significantly (p≤0.05) effected height of cassava plant but this varied among all accessions.. Also, among the four accessions studied Ankrah and Tuaka were the most promising accession in terms of callus induction and somatic embryo formation ability.Item Anatomical, Germination And In Vitro Studies On Shea Tree (Vitellaria Paradoxa C.F.Gaertn.) Seed(University of Ghana, 2013-07) Iddrisu, A.In vivo and in vitro germination and regeneration studies were conducted on the development of Vitellaria paradoxa seedlings as an initial effort towards its domestication. However, to achieve this objective, the morphology and anatomy of the seeds were first studied because they influence germination. Although a smooth, brown coat encloses a V. paradoxa seed, it did not impose dormancy on the embryo. Transverse and longitudinal sections through the seed showed that the embryo is surrounded by latex- and fat-containing tissues which made its identification difficult. Thus, the embryo was identified by immersing transversely cut seeds in 1.0 % tetrazolium chloride (TTC) solution for 24 hours which stained it red. When V. paradoxa seeds of similar size were sown on nursery beds, the resulting seedlings developed through seven stages namely sprouting, pseudoradicle elongation, bulging, appearance of the shoot on the pseudoradicle, shoot elongation, emergence and seedling establishment. The pseudoradicle is the fused petioles of the two cotyledons and a transverse section through it revealed an outer sheath and lactiferous vessels surrounding a central hollow tube. Longitudinal section also showed the lactiferous vessels surrounding the central hollow tube in which the plumule moves through until it reaches the bulge of the pseudoradicle where it develops into a rudimentary shoot. The rudimentary shoot then protrudes from the pseudoradicle and grows upwards. Classifying seeds into three groups based on sizes and sowing them on nursery beds showed that seed size significantly affected days to germination and the morphology of the resulting seedlings. Large seeds germinated within one week after sowing with vigorous growth compared to small and medium seeds. Although the seedcoat of V. paradoxa never imposed dormancy, deshelling (removal of the seedcoat) significantly led to early germination and synchronous seedling emergence compared to those for intact seeds (control). In vitro culture of intact and deshelled seeds on Murashige and Skoog (1962) basal salts modified with 6-benzylaminopurine (BAP) produced no plantlets although 80 % of the deshelled seeds developed long pseudoradicles on a medium supplemented with lower concentration of BAP (1.0 or 2.0 mg/l). Similarly, the culture of TTC identified embryonic axes did not produce plantlets, but rather significantly long pseudoradicles were produced with BAP having significant effect on pseudoradicle development. Contrastingly, in vitro culture of excised rudimentary shoots on the same MS medium modified with BAP and naphthaleneacetic acid (NAA) produced plantlets with distinct shoots and leaves. Significant reduction in days to emergence of seedlings from deshelled seeds and successful in vitro plantlet development using rudimentary shoot explants will enhance nursery establishment of this economically important tree species for domestication and reafforestation programmes in sub-Saharan Africa.Item Characterisation And Determination Of Virus Resistance Among Cowpea [Vigna Unguiculata (L.) Walp.] Genotypes(University of Ghana, 2017-07) Tettey, C.K.Several households in Ghana feed on cowpea [Vigna unguiculata (L.) Walp.] which serves as good source of protein. However, cowpea viral diseases and the lack of adaptable cultivars have become a limiting factor in cowpea production. This work therefore sought to explore morphogenetic diversity and viral resistance traits in cowpea germplasm to improve productivity. Thirty-eight exotic and local cowpea genotypes were cultivated at the Teaching and Research Field of the School of Agriculture, the University of Cape Coast. Two plants were maintained per stand at planting distance of 50 cm x 30 cm with three replications in a randomized complete block layout during the major (June – September) and minor seasons (November – February). The cowpea genotypes were characterised using both morphological and molecular methods to assess diversity in the coastal savanna agro-ecological zone of Ghana. They were also screened for resistance to cowpea viruses using visual scale on-field and DAS-ELISA protocol. The cowpeas showed significant (P < 0.05) variations in plant height, canopy diameter, number of branches, area of leaf, days to 50% flowering, days to pod maturity, pod length, number of seeds per pod and hundred seed weight. There were significant and positive correlations between pod weight and seed yield (r = 0.985, P < 0.05), plant height and canopy diameter (r = 0.576, P < 0.05), canopy diameter and number of branches (r = 0.576) as well as pod length and the number of seeds per pod (r = 0.530, P < 0.05). Hundred seed weight ranged from 10.03 g to 22.7 g. On the whole, 23 quantitative and qualitative parameters differentiated the cowpea genotypes into two main clusters with sub-clusters. Genomic analysis involving nine polymorphic SSR primers showed a mean genetic diversity of 0.7, polymorphic information content of 0.67 and allele frequency of 0.4 among the cowpea genotypes, which were differentiated into two main clusters with sub-clusters. Incidence and severity of cowpea viruses in both the major and minor seasons were significantly (P < 0.05) different among the cowpea genotypes as well as between the two seasons with the minor season showing the higher mean incidence (53.1%) and severity (1.99) compared to 30.9% incidence and 1.49 mean severity recorded for the major season. Of the four cowpea viruses screened on 15 best performing cowpea genotypes using DAS-ELISA, two viruses, Cowpea severe mosaic virus (CPSMV) (1/15) and Cucumber mosaic virus (CMV) (13/15) were detected with one mixed infection CPSMV/CMV recorded in the local genotype Padi-tuya. IT04K-321-2 alone was devoid of viruses and could be resistant but requires further confirmation prior to incorporation into future breeding programmes.Item Propagation And Molecular Characterisation Of Rubber Tree (Hevea Brasiliensis Muell. Arg.) In Ghana(University of Ghana, 2015-07) Antwi-Wiredu, A.The study was aimed at the propagation and molecular characterisation of some introduced clones of Hevea brasiliensis in Ghana. Propagation of H. brasiliensis by stem cuttings and in vitro techniques was used to study alternative procedures for mass production of rubber planting materials. Brown and green stem cuttings of Clone I and Clone II were soaked for 6 hours in 0.0-22.5g/L NAA followed by propagation in a nursery bag filled with nutrient-rich soil. Only the brown stem cuttings of H. brasiliensis survived. The % survival, length of shoots, number of roots as well as length of roots of Clone II was significantly (P<0.05) higher than Clone I. Stem cuttings treated with 15.0g/L NAA significantly (P<0.05) developed higher shoots (83.33%), number of roots (6.167), length of shoots (15.38cm) and length of roots (6.00cm) than the remaining treatments. There was significant (P<0.05) effects of NAA and Clone II in sprouting and rooting growth of the brown stem cuttings. The addition of 5.0mg/L kinetin in the MS culture medium significantly (P<0.05) enhanced higher shoot development (84.00%), number of shoots (3.60) and leaves (23.40) of the shoot-tip explants compared to other treatments. In nodal explants cultured on a medium without kinetin developed higher shoots (94.00%), height of shoot (4.80cm), number of leaves (19.20), number of shoots (6.00) and number of roots (7.00) than those with kinetin treatments. However, 7.5mg/L kinetin of the nodal culture also performed significantly after the controls. A dendrogram derived from the UPGMA distinguished the rubber clones from four areas of Ghana into two clusters. The five SSR markers showed high degree of relatedness among the rubber clones which suggested high genetic similarity (IRCA317-5, IRCA41-2, IRCA331-6, IRCA230-4, IRCA109-3, B8-23) and some degree of diversity/variation (K2-18, IRCA840-7, PB217-8, PB217-10, IRCA317-16) among the clones. Thus, clones of interest could be selected for future breeding and propagation programmes. Successful in vivo and in vitro propagation as well as molecular characterisation (genetic similarity and diversity) of rubber tree (Hevea brasiliensis) in Ghana were achieved.Item Intra-Specific Hybridisation and Performance Evaluation of Hybrid Lines of Roselle (Hibiscus Sabdariffa L.)(University Of Ghana, 2015-03) Kwofie, J.Roselle (Hibiscus sabdariffa L.) is an important multi-purpose crop in Ghana and across West Africa, used as a source of food as well as raw material for medicinal and industrial applications. However, due to limited research efforts to gather relevant information on breeding behaviour and inheritance of desirable traits of existing cultivars to enhance yield and nutritional contents, economic potential of the crop has not been fully exploited. The present study was therefore initiated with a broad objective of assessing breeding behaviour and nature of inheritance of selected qualitative and quantitative traits and also variability with respect to agro-morphological characteristics, as well as nutritional composition of leaves and calyces, among 20 local accessions of roselle (Hibiscus sabdariffa L.); comprising 6 accessions of H. sabdariffa var altissima and 14 accessions of H. sabdariffa var sabdariffa. The accessions were collected from three major production regions of Ghana (Northern, Volta and Western). The investigations were carried out at the research fields and laboratories of Biotechnology and Nuclear Agriculture Research Institute (BNARI) from April 2013 to November 2014. All six accessions of var altissima were able to hybridize with one another in both direct and reciprocal cross combinations with high degree of crossability success (30 % to 80 %). On the other hand, cross compatibility among the 14 accessions of var sabdariffa was direction-dependent, and crossability success was low (0.00 % to 43.33 %), as some parents could only be used as males or females. Parental lines A3 and A11 emerged as most compatible male and female respectively. Crossability success was relatively high during early hours of the day but decreased continuously in subsequent hours. Fourteen parental accessions and 25 F1 progenies of var sabdariffa evaluated for 23 agro-morphological traits exhibited significant variations in all quantitative traits studied. Clustering pattern based on both qualitative and quantitative traits largely reflected colour and size of calyx. Leaf and calyx traits showed strongest positive association among pairs of quantitative traits investigated. Accessions D2, D3, D4 and D6 exhibited highest general combining ability for major yield traits; days to first flowering, number of fruits per plant, plant height and stem basal diameter, while D2 x D5, D5 x D2, D2 x D4, D6 x D5, D3 x D6 and D6 x D4 emerged as most promising in specific cross combinations following a diallele experiment. Concentrations of the various nutrients were generally higher in calyces compared to the leaves. Except for total titrable acid and vitamin C contents, F1 offspring performed better on all other parameters than their parental accessions and control varieties. Calyces of A11 x A1 and A11 x A13 contained highest protein, ash and pH contents and relatively low moisture as well as highest concentration of K (3284.04±0.01 mg/100 g), Fe (19.45±0.02 mg/100 g) and Ca (1360.70±1.0 mg/100 g), while A4 x A1 recorded highest concentrations of Mg (4.30±0.88 mg/100 g). With regards to the leaf samples, A7 x A12 produced highest values for Ca (1440.20±1.00 mg/100 g) and Fe (15.59±0.01 mg/100 g), while A11 x A2 gave highest Mg (2.72±0.13 mg/100 g) and Na (32.93±1.15 mg/100 g) contents. Similarly leaves of A2 gave highest concentration of K (1641.08±0.01 mg/100 g). These results demonstrate possibility of producing superior hybrids of roselle through artificial cross-pollination. Key recommendations based on these findings include: i) ascertaining specific barriers to crossability between accessions of H. sabdariffa var sabdariffa and H. sabdariffa var altissima to aid transfer of useful traits between them. ii) use of molecular markers to confirm results of morphological characterisation and also to better understand inheritance of qualitative traits. iii) composite breeding to incorporate as many desirable traits as possible into one or two improved (standard) variety/varieties.Item Hybidization Studies in Okra (Abelmoschus spp (L.) Moench)(University of Ghana, 2016-07) Amitaaba, TOkra (Abelmoschus spp. L. Moench) is an important multi-purpose vegetable crop cultivated and consumed across all tropical and temperate regions of the world. In Ghana, it is popular in all ten regions and increasing quantities are exported to Europe in the fresh form. The crop has received little attention by way of breeding to produce varieties combining the most desirable qualities to boost local cultivation and export. Ten accessions of Abelmoschus spp., comprising two species, A. esculentus (T1, T2, T3, VT, ID and AG) and A. callei (KB, AM, YL and T4) collected from six geographical regions of Ghana were crossed in all possible combinations to assess inter-specific as well as intra-specific hybridisation between and within species. Reciprocal crosses were also carried out and the performances of their F1 offspring were evaluated against the respective parents for expression of heterosis for key quantitative traits including days to 50% germination, days to 50% flowering, plant height, fresh fruit weight, length of pod and number of seeds per pod. Genetic relatedness among the accessions and their progeny was established by way of a dendrogrom based on furthest neighbour method (Euclidean). All six accessions of Abelmoschus esculentus were able to hybridize with one another in both direct and reciprocal cross combinations with high degree of crossability index (CI) (45.71% to 90.32%). On the other hand, cross-compatibility among A. esculentus and A. callei was successful only in one direction when A. esculentus was used as females also with a CI between 34.48% and 60%. Parental lines T3 and T1 emerged as the most compatible female and male respectively. Crossability success was relatively high during early hours of the day but decreased continuously in subsequent hours. Ten parental accessions and 61 Fl progenies of A. esculentus and A.callei evaluated for 15 qualitative and 8 quantitative traits exhibited significant variations in all quantitative traits studied. Clustering pattern based on quantitative traits largely revealed no duplicates and clustering pattern especially among parental accessions, appears to reflect relationship based upon speciation as parental accessions belonging to A. caillei are clustered towards one end of the dendrogram, while members belonging to A. esculentus clustered towards the opposite end. Contributions of the three principal components were 45.98 %, 23.31 %, and 14.46% for the first (PC1), second (PC2) and third (PC3) respectively, with corresponding Eigen values of 3.21837, 1.63171 and 1.01212 respectively, cumulating into maximum of 83.75 % of total variance. These results demonstrate possibility of producing superior hybrids of okra through artificial cross-pollination. Key recommendations based on these findings include i) use of molecular markers to confirm results of morphological characterisation and also to better understand inheritance of qualitative traits. ii) Genes linked to agronomically important traits in okra should be genetically mapped through Quantitative Traits Loci (QTLs) to serve as a baseline data platform for researchers and breeders.iii) Further studies on inheritance of qualitative traits stretching to the F2 or even F3 generations should be carried out, preferably using molecular markers to fully understand the pattern of segregation with appropriate ratios.