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Background Understanding end-users’ preferred breeding traits and plant management practices is fundamental in defining sound breeding objectives and implementing a successful plant improvement programme. Since such knowledge is lacking for Synsepalum dulcificum, a worldwide promising orphan fruit tree species, we assessed the interrelationships among socio-demography, ecology, management practices, diversity and ranking of desired breeding traits by end-users of the species (farmers, final consumers and processing companies) in West Africa. Methods Semi-structured interviews, field-visits and focus groups were combined to interview a total of 300 farmers and final consumers belonging to six sociolinguistic groups sampled from three ecological zones of Benin and Ghana. One processing company in Ghana was also involved. Data collected included socio-demographic characteristics; crop management systems and practices; and preferences of farmers, final consumers and processing companies and ranking of breeding traits. Data were analysed using descriptive statistics, independence, and non-parametric tests, generalized linear models, multi-group similarity index and Kendall’s concordance coefficient. Results Men (86.33% of respondents) were the main holders of S. dulcificum in the study area. The three most frequent management practices observed in the species included weeding, fertilization and pruning, which were applied by 75.66%, 27.33% and 16.66% of respondents, respectively. The management intensity index varied significantly across ecological zones, sociolinguistic groups, and instruction level (p < 0.001) but was not affected by gender (p > 0.05). General multigroup similarity indices ($$ {\mathrm{C}}_{\mathrm{S}}^{\mathrm{T}} $$ C S T ) for farmer-desired traits, on one hand, and final consumer-desired traits, on the other hand, were high across ecological zones ($$ {\mathrm{C}}_{\mathrm{S}}^{\mathrm{T}} $$ C S T ≥ 0.84) and sociolinguistic groups ($$ {\mathrm{C}}_{\mathrm{S}}^{\mathrm{T}} $$ C S T > 0.83). Nevertheless, respondents from the Guineo-Congolian (Benin) and the Deciduous forest (Ghana) zones expressed higher agreement in the ranking of desired breeding traits. Preference for breeding traits was 60% similar among farmers, final consumers, and processors. The key breeding traits desired by these end-users included in descending order of importance big fruit size, early fruiting, high fruit yielding (for farmers); big fruit size, high fruit miraculin content, fruit freshness (for final consumers); and high fruit miraculin content, big fruit size, high fruit edible ratio (for processing companies). Conclusion This study revealed stronger variations in current management practices across ecological zones than across sociolinguistic groups. A high similarity was shown in end-users’ preferences for breeding traits across the study area. Top key traits to consider in breeding varieties of S. dulcificum to meet various end-users’ expectations in West Africa include fruit size and fruit miraculin content. These results constitute a strong signal for a region-wide promotion of the resource. more...

Kola (Cola nitida (Vent.) Schott & Endl.) is a tree crop of great economic and socio-cultural importance. Available genetic resources of kola are increasingly vulnerable to genetic erosion due to decreased population sizes resulting from land use changes and cutting of trees for timber and firewood production. There is therefore an urgent need to conserve genetic resources of kola in Ghana. The objective of this research was to map distribution, ascertain status of collection and conservation of kola in Ghana and to collect germplasm from mapped provenances for characterization and breeding of improved varieties. Mapping of distribution of kola was carried out by undertaking trips to kola growing areas in Ghana. Transects were constructed and an inventory of C. nitida was carried out using GPS. The geo-references were interpolated into the map of Ghana using ArcGIS software. The spatial analysis showed Jasikan, Akaa, Ahamasu, Ampeyo, Pampawie, Oyoko, Akwadum, Jejeti, Atwedie, Kwahu, Asuom, Tweapease, Kade, Twifo Praso, Assin Fosu, Ntafrewaso, Hemang, Jamasi, Kona, Bipoa, Offinso, Akumadan and Aframcho as the areas with a dense natural populations of C. nitida. The current knowledge and understanding of distribution of kola resources provides opportunity to have a comprehensive collection of genetic resources of kola in Ghana. This aided in collection of 102 new accessions from 22 provenances in the Volta and Eastern regions of Ghana. This in addition to 226 earlier collections constitute 328 accessions of C. nitida in Ghana. The evaluation and understanding of diversity of these kola resources could offer yet-unknown traits of high economic value for further domestication and development of improved varieties. more...

Eggplant (Solanum melongena L.) is one of the most important fruit vegetables in the world, with several nutritional and medicinal benefits. However, little is known about the genetic divergence of yield and its related traits. The objective of this study was to explore gene action and heritability of traits to help direct and strengthen breeding programmes, geared towards improving yield of the crop. Six generations (P1, P2, F1, F2, BC1 and BC2) derived from two crosses (SM001-07 x ST004-03 and SM001 x San005-01) of eggplant accessions, were grown in pots in an open field, using Randomised Complete block Design (RCBD). Estimated data indicated that, the additive-dominance model was adequate to demonstrate the genetic variation and its significance in the inheritance of fruit weight, days to flowering and fruit yield traits. Although non-allelic interactions were found in plant height and number of seeds, additive effect was more pronounced in the genetic control of days to flowering and fruit weight; while dominance effect was more important in the control of plant branching and fruit length. Plant height and fruit yield were influenced by complementary gene action. Furthermore, the study revealed low magnitudes of dominance and environmental variances for most traits showing higher heritability values. In view of the diverse gene actions, with additive, dominant and epistasis, playing significant roles in the control of different traits, backcross, recurrent selection or bi parental could be appropriate for advancing the segregating populations to meet the need of yield improvement in both crosses. Key words: Additive, dominance, Epistasis, gene action more...

Identification of heterotic groups and efficient testers, which are important prerequisites for the development of outstanding hybrids, has been a major challenge to its success, especially for early and extra‐early germplasm. This study was carried out to (a) identify the most efficient heterotic grouping method for classifying a set of inbred lines and (b) determine the efficiency of testers in classifying inbred lines into heterotic groups. A total of 205 hybrids obtained by crossing 41 inbred lines with five standard testers were evaluated together with five hybrid checks under drought, low soil nitrogen (N), Striga‐infested and optimal environments in Nigeria between 2014 and 2016. The heterotic group's specific and general combining ability (HSGCA) method was more effective in classifying the inbred lines into heterotic groups. Testers TZEI 17 and TZEI 23 were the most efficient across environments and could be invaluable for classifying other lines into heterotic groups and assessing combining ability of maize inbreds. In addition, these testers and heterotic groups represent an invaluable resource for development of outstanding hybrids in sub‐Saharan Africa (SSA). more...

Tigernut (Cyperus esculentus L.) is a nutritious crop of the sedge family. In Ghana available local accessions have not been collected and characterized for conservation and utilization purposes. The objective of this study was to collect, conserve and characterize twenty-four local accessions of tigernut in Ghana based on agro-morphological traits. The ANOVA revealed significant (p more...

The study of genetic diversity of any germplasm helps to facilitate its use and management. This experiment was carried out to determine the genetic diversity among 87 rice accessions from six countries. Seventeen quantitative traits were recorded based on the internationally accepted standard evaluation system for rice from IRRI. Analysis of variance, principal component analysis (PCA) and correlation amongst quantitative traits were carried out. Highly significant (P more...

The study sought to assess combining ability and establish the gene action involved in the inheritance and heritability of yield and yield components in taro. Five (5) parents and twenty (20) F1 hybrids generated from hybridization were evaluated in 3 locations in Ghana. The field trials were laid in RCBD with three replications. Data measured included number of stolons, number of suckers, corm length (mm), corm width (mm), corm weight (g), yield (kg/ha) and dry matter content. Analysis of variance (ANOVA) was conducted using Statistical Tool for Agricultural Research version 2.0.1. Griffing Method II, Model 1 diallel analysis was used to estimate the general and specific combining ability. Heterosis was estimated for all the F1 hybrids. Heritability and correlation among the traits was also estimated. The ANOVA revealed significant differences among the genotypes for yield and its components. The high magnitude of SCA over GCA, high broad sense heritability over narrow sense heritability and below unity Bakers ratio observed for most of the yield traits studied indicates the predominance of non-additive gene action in the expression of the traits. The highly significant positive heterosis and above parental means recorded for the progenies indicates that effective progress can be made in the development of high yielding varieties of taro. CE/IND/16 which recorded significant positive GCA for all the traits except for number of stolons can be included in hybridization programs for varietal development in taro. Hybrids: CE/MAL/32 $$\times $$ KAO19, KAO19 $$\times $$ CE/IND/16, CE/IND/16 $$\times $$ KAO19 and CE/IND/16 $$\times $$ BL/SM/10 which had high hybrid vigor across the research environments could be further evaluated in other environments to ascertain their potentials for release to farmers for cultivation. Significant positive association observed between corm weight and yield/ha(kg) and corm width (mm), indicates that breeding for high corm weight and corm width will definitely improve the yield of taro. more...

Cassava (Manihot esculentaCrantz) is an important industrial and staple crop due to its high starch content, low input requirement, and resilience which makes it an ideal crop for sustainable agricultural systems and marginal lands in the tropics. However, the lack of genomic information on local genetic resources has impeded efficient conservation and improvement of the crop and the exploration of its full agronomic and breeding potential. This work was carried out to obtain information on population structure and extent of genetic variability among some local landraces conserved at the Plant Genetic Resources Research Institute, Ghana and exotic cassava accessions with Diversity Array Technology based SilicoDArT and SNP markers to infer how the relatedness in the genetic materials can be used to enhance germplasm curation and future breeding efforts. A total of 10521 SilicoDArT and 10808 SNP markers were used with varying polymorphic information content (PIC) values. The average PIC was 0.36 and 0.28 for the SilicoDArT and SNPs respectively. Population structure and average linkage hierarchical clustering based on SNPs revealed two distinct subpopulations and a large number of admixtures. Both DArT platforms identified 22 landraces as potential duplicates based on Gower’s genetic dissimilarity. The expected heterozygosity which defines the genetic variation within each subpopulation was 0.008 for subpop1 which were mainly landraces and 0.391 for subpop2 indicating the homogeneous and admixture nature of the two subpopulations. Further analysis upon removal of the duplicates increased the expected heterozygosity of subpop1 from 0.008 to 0.357. A mantel test indicated strong interdependence (r = 0.970; P < 0.001) between SilicoDArT and DArTSeq SNP genotypic data suggesting both marker platforms as a robust system for genomic studies in cassava. These findings provide important information for efficientex-situconservation of cassava, future heterosis breeding, and marker-assisted selection (MAS) to enhance cassava improvement. more...

The use of kola nut, including natural or alternative medicinal sources, has inevitably created an increased global market demand in excess of its production and provides great prospects for the growth of the kola nut industry in producing countries like Ghana. Nonetheless, there is a great dearth of information on Ghana’s kola nut supply-side practices and constraints that can provide a basis for the development of the industry. This study fills the research gap by describing the practices and constraints of farmers, processors, and marketers of kola nut in Ghana. Using a survey methodology, results showed that nearly all (99.5%) farmers interviewed had not received any extension training on agronomic practices. Low market price of nuts (61.5%) and pests and diseases (60.4%) were the most reported constraints to kola nut production. Chiefs among motivating factors for cultivating kola nut were alternative livelihood support (58%). Some processors (28.6%) who rinsed nuts after depulping used a solution of Akate Master (bifenthrin) and others (51.0%) used fumigation tablets (aluminium phosphide) (91.0%) for storing the nuts. However, these chemicals may be dangerous to the health of consumers in the long run. The low selling price of kola nuts was perceived to be the most (74.8%) constraint to kola nut processing and marketing. Respondents noted that the red nuts were preferred for their durability during transportation and longer shelf life, while the white nuts were preferred for their taste. The results suggest the need for further agronomic, postharvest handling, preservation, and storage, as well as breeding research to provide recommendations to farmers and processors. To overcome some marketing challenges, there is a need for policy support to standardize pricing and grading systems for the mutual benefit of all the stakeholders. more...

The miracle plant Synsepalum dulcificum is a multipurpose natural sweetener and a promising West African orphan fruit shrub candidate for genetic improvement. Unfortunately, basic knowledge such as phenotypic variation and inheritance estimates required for implementing a breeding program are still lacking. A set of 203 accessions were sampled in two habitats from seven populations spread across the Dahomey Gap (DG) and the Upper Guinea forest (UG) in West Africa. The phenotypic diversity and allometric relationships among functional traits were analysed; the broad-sense heritability was estimated for fruit-traits, and a mini-core collection was developed in the species. Quantitative variation in tree- and fruit-traits was recorded, and multivariate analyses were performed to assess relationships among accessions, whereas heritability was estimated using the coefficient of repeatability. Tree-traits observed in S. dulcificum were more variable than fruit-traits. While habitat-type only affected tree-traits, the provenance population significantly affected both fruit- and tree-traits, with the UG populations outperforming the DG ones. Significant correlations were observed among fruit-traits on one hand, and among tree-traits on the other hand, whereas poor correlations were observed between tree- and fruit-traits. The multivariate analysis grouped accessions in three clusters. Promising individuals for high fruit mass and pulp-dense genotypes’ selection were identified within clusters. Repeatability estimates for fruit-traits ranged from 0.015 (edible ratio) to 0.88 (fruit mass). The Core Hunter algorithm enabled the extraction of 41 individuals as robust representatives of the initial set of 203 accessions, and the mapping of this core collection suggested Dahomey Gap as a centre of diversity of the species. These original findings offer opportunities, not only for the genetic improvement of S. dulcificum, but also for targeted ex-situ conservation in the species. more...

Cola nitida known as Kola serves as flavouring ingredient in the food industry and is also of great importance during traditional rites in Africa. Despite the well-known pharmaceutical values of the species, efforts to develop improved varieties with enhanced nutraceutical quality is limited due to unavailability of information on variation of genotypes in bioactive compounds in the nuts. The objectives of this research were to evaluate 25 genotypes of kola for bioactive contents, determine relationship between nutritional and phenolic traits and to identify kola genotypes with good nutraceutical quality for use in developing improved varieties. The kola genotypes were established in the field using a randomized complete block design with three replicates. Nuts harvested from the blocks, were bulked and used to quantify soluble and insoluble sugars, total protein, moisture, ash, fats, pH, polyphenols, tannins and flavonoids using completely randomized design with three replicates in the laboratory. Data were analysed by combining Analysis of Variance, Kruskal-Wallis test, correlation test and multivariate analysis. Significant variations (P < 0.05) were observed among the kola genotypes for the bioactive traits evaluated. Phenolic traits were more heritable than nutritional traits. Although not significant (P > 0.05), correlation between nutritional and phenolic traits was negative, whereas correlations among nutritional traits were weak. On the contrary, significant and positive correlations (P < 0.05) were observed among phenolic traits. The hierarchical clustering analysis based on the traits evaluated grouped the 25 genotypes of kola evaluated into four clusters. Genotypes A12, JB4, JB19, JB36, P2-1b, and P2-1c were identified as potential parental lines for phenolic traits selection in kola whereas genotypes A10, Club, Atta1 and JB10 can be considered for soluble and insoluble sugar-rich variety development. These findings represent an important step towards improving nutritional and nutraceutical quality of kola nuts. more...

Cowpea is a grain legume that is grown extensively as an alternate protein and income source for many smallholder farmers. Characterising cowpea root phenotypes could provide the basis for developing genotypes with root system architecture (RSA) traits that increase soil resource acquisition. Measuring RSA traits of any field crop is a demanding task, in terms of expediency, time, cost, and competence. Targeted root phenotyping strategies focusing on a few relevant traits might aid in side-stepping some of the challenges associated with phenotyping roots of field crops. The objectives of this study were to (i) measure genotypic variation for RSA and shoot traits of cowpea genotypes; and (ii) identify candidate variables and genotypes that contribute the largest share of variance. Sixty cowpea accession were grown in field trials at the University of Cape Coast, Ghana. Seventy variables, mostly quantitative RSA traits were measured. Multivariate analysis was used to determine major traits contributing to variation. There were significant differences (P more...

Black pod caused by Phytophthora species is a devastating disease of cacao (Theobroma cacao L.) in production regions worldwide. Breeding for cacao genotypes resistant to black pod disease is crucial for sustainable cocoa production and profitability. Although breeding programmes in the past have made considerable efforts in improving resistance of cocoa genotypes with diverse genetic background, the disease continues to cause unacceptable yield losses in cacao production. To understand the mode of inheritance of epicuticular wax on the surface of cocoa pod known to play a major role in resistance to black pod disease, a 6 × 6 full diallel and a M x N (6 × 4) mating designs were used and data was analysed using Griffing’s method I model I approach and the North Carolina design –II approach, respectively. The results of the two mating designs were consistent and showed that epicuticular wax on leaf and pod surfaces of cacao were under the control of additive genetic effects. The non-additive effects were generally much smaller compared to the additive genetic effects. The significant association between GCA estimates of parents and their means indicates that parental values could be used as indicators of progeny performance. The best general combiners for epicuticular wax load on leaf and pod surfaces were Pa7/808, T60/887 and Pa 150. The larger additive components and heritability observed in this study, indicates that pedigree selection could be used to develop cacao cultivars with high amount of epicuticular wax on pod surface to enhance resistance to black pod disease. more...

Maize (Zea mays L.) is an important cereal crop cultivated across all agro-ecologies in Ghana, but productivity in farmer's fields is generally low (1.7 t/ha). The low maize productivity is attributed to the continuous use of low-yielding varieties among others. Hybrid maize varieties have proven to be high yielding than unimproved varieties, therefore, farmers' adoption would reduce the deficit of demand and supply of maize in Ghana. A study was conducted to assess the relative yield performance and stability of 45 extra-early single-cross hybrids. The trial was conducted in the Forest, Forest-Transition and Coastal savannah zones over the main season of 2015. The experiment was laid-out in a randomized incomplete block design with three replications at each location. Data were collected on grain yield (GY) and other agronomic traits for each location. Results showed significant mean squares for environment (E), genotype (G) and G × E interaction for GY and other agronomic traits suggesting that the test environments were unique to contribute to the expression of genetic variability of the hybrid genotypes. Hybrids 28 (TZEEI 78 × TZEEI 66), 2 (TZEEI 64 × TZEEI 61), 18 (TZEEI 66 × TZEEI 64) and 41 (TZEEI 94 × TZEEI 76) were identified as high yield and most stable under the test environments. Moreover, hybrid 28 was the ideal and most yielding hybrid and should extensively be tested on-farm for consistent yield performance and then released to farmers for commercialization. more...

Spider plant (Cleome gynandra L.) is one of the most important and highly prioritised African leafy vegetables consumed in many parts of Africa due to its rich source of vitamins A and C and minerals such as calcium, iron, magnesium and protein. In order to improve upon yield and promote the breeding of improved cultivars, this study was carried out to understand variation in morpho-agronomic characters of twenty-four accessions of Cleome gynandra in Ghana. The accessions were evaluated for morpho-agronomic traits using Completely Randomized Design (CRD) with three replications. There were variations among the accessions in terms of growth habit, stem pubescence, stem colour, flower colour and petiole colour. Significant differences (p more...

Cleome gynandra is one of the most promising African leafy vegetables consumed in most parts of Africa. The crop is a rich source of vitamins A and C and minerals such as calcium, iron, magnesium and protein. The leaves and seeds of spider plant are used in indigenous medicine in several countries. Despite the numerous nutritive benefits and ethnopharmacological uses of the plant, C. gynandra is still underutilized due to lack of awareness and promotion of production technologies and utilization. Available information is limited and short on several relevant and rudimentary components. Hence, this review focuses on the current knowledge on C. gynandra, with regards to its botany, ecology, cultivation systems, utilization, nutraceutical properties as well as the breeding avenues that will contribute to promoting the species, aimed at ensuring food and nutritional security and efficient management of its genetic resources. Breeding programmes aimed at minimizing the bitterness of the leaves so to arouse the interest of consumers, and the mechanisms involved in the responses and adaptation of C. gynandra as a C4 plant to salinity stress, were also explored. more...

Wild relatives of eggplants represent a good source of variation for breeding programmes, in particular for traits related to biotic and abiotic stresses and also fruit quality traits. However, wild species remain largely unexploited for eggplant breeding compared to other crops like tomato. Seven cultivated eggplant accessions (SM001-02, SM001-04, SM001-06, SM001-07, SA002-02, SA002-03 and SMA003-03) were crossed with three wild accessions (ST004-03 (Solanum tovum), San005-01 (Solanum anguivi) and SA002-08 (Solanum aethiopicum)) in an open field using completely randomized design. The success of fruit and seed set as well as seed germination depended on the cross combination and the direction of the cross. In this regard, no fruit set was recorded when the wild accessions were used as female parents. The highest fruit set and mean number of seeds/fruit was obtained from the crosses Sm001-07 × ST004-03 (6%; 264 seeds) and Sm001-07 × San005-01 (5.7%, 114 seeds), respectively. The germination of hybrid seeds was recorded in only three crosses, SM001-07 × ST004-03, SM001-07 × San005-01 and SA002-02 × San005-01 with germination range from 3.3 to 16.6%. However, plantlets from these seeds did not survive after two weeks of germination. The hybridity of the putative interspecific F1 hybrids (through tissue culture) was confirmed with a morphological marker. These hybrids obtained will contribute to broadening the genetic background of cultivated eggplant species used in this study and to the genetic enhancement of this crop. Key words: Crossability, eggplant, fruit set, germination, introgression, seed set, wild relatives. more...

Solenostemon rotundifolius is a very important tuber staple for both rural and urban communities in West Africa. The crop is rich in nutrients as compared with other root and tuber crops and is germane to ensuring food and nutritional security. It is also of great medicinal importance and is known to lower blood cholesterol levels as well as fend off fungal and viral infections in humans. However, very little is known about the breeding avenues necessary to improve upon the crop. Also, not much interest has been generated with regards to production of the crop owing to its low yield and small tuber size. This review elucidates the current knowledge and breeding avenues for increasing the genetic base as well as improving upon the existing cultivars of the crop. Breeding objectives may be geared towards the development of high yielding cultivars with bigger tuber sizes in order to increase the marketable value of the crop. Tissue culture avenues should be exploited to induce somaclonal variants, so as to increase the genetic diversity necessary for the improvement of the crop. Chemical mutagens could be employed to alter the size and number of tubers that the crop produces. Present ex situ and in situ conservation strategies need to be reinforced. Further studies should be carried out into the cryopreservation of Frafra potato genetic resources. more...

Rice is an important staple food crop that feeds over half of the global population and it has become the cereal that provides a major source of calories for the urban and rural poor in Africa. This research aimed to use simple sequence repeat (SSR) markers to evaluate the genetic diversity in rice (Oryza sativa and Oryza glaberrima) germplasm as breeding method. In the present study, 16 SSR markers were used across 48 genotypes or accessions obtained from Central Agricultural Research Institute (CARI), Suakoko, Liberia and Plant Genetic Resources Research Institute (PGRRI), Bunso, Ghana. DNA was extracted from 48 plants per accession without bulking to check the purity of the accession using the 16 SSR markers. Sixteen primers were acquired out of 20 primers which showed DNA amplification and polymorphism among the 48 rice accessions. The numbers of alleles detected by these 16 primers ranged from 1 to 16 with a mean of 5.25, while polymorphism information content (PIC) ranged from 0.06 to 0.66 with a mean of 0.35. The SSR markers were highly informative as generated by the power marker V3.25 software. The unweight pair group method with arithmetic averages (UPGMA) cluster dendrogram generated based on the 16 SSR markers grouped the accessions into 11 main clusters. At the similarity coefficients of 90%, the highly distance genetic diversity was found between 2 accessions; ACSS37 and ACSS1. Cluster X was the largest of all the clusters, while clusters VII and VIII were the second largest clusters with 7 accessions each. The outcome of this study should be useful to manage the gremplasm conservation and future rice genetic improvement. Key words: Germplasm, genetic diversity, molecular markers, polymorphism, sequence repeat. more...

Availability of multiple-stress tolerant maize is critical for improvement in maize production in West and Central Africa (WCA). A study was carried out to (i) assess a set of inbred lines for combining ability under stressed and optimal conditions, (ii) determine the performance of the testcrosses under different conditions, and (iii) identify outstanding hybrids across the conditions. Two hundred and five testcrosses were planted with five hybrid checks under Striga-infested, low soil nitrogen, drought and optimal conditions between 2015 and 2016 in Nigeria. The grain yield inheritance under optimal condition was largely regulated by additive gene effect whereas non-additive gene effects largely regulated grain yield under the three stresses. Four of the inbreds had significant positive general combining ability effects each under low N and drought, and three under Striga infestation for grain yield. The inbreds could be vital sources of beneficial alleles for development and improvement of tropical yellow maize hybrids and populations. Hybrids TZEI 443 x ENT 13 and TZEI 462 x TZEI 10 were high yielding and stable; they out-performed the three early maturing released hybrids in WCA. The new hybrids should be extensively assessed and released in the sub-region to improve food security. more...

Eggplants (Solanum spp.) are important vegetable crops, well known for nutritional and medicinal values of their fruits and leaves. In order to select more nutritious varieties in Ghana, 33 eggplant accessions were investigated for nutritional, mineral and antioxidant content of their fruits. Proximate and antioxidant analysis were determined by AOAC and DPPH methods. The results showed significant differences (P1.5 contributed 68.68% of total variability. Dry matter, protein, moisture and carbohydrate contents showed maximum contributions to the total variability. Biplot analysis displayed strong and positive associations among ash, protein and moisture with dry matter; moisture and carbohydrate and; protein and ash. Accessions San 005-01, San 005-02, SA 002-07, SA 002-08 and ST004-03 were identified as good sources of nutrients, minerals and antioxidant properties among the others; and could be used as potential donors for hybridisation programme to develop varieties with higher concentration of these traits.Key words: Carbohydrates, mineral, nutritional, Solanum more...

Groundnut yield is constrained in most cases by early and lateleaf spots diseases. Selection and breeding for resistance will enhance yields. Therefore, this study was conducted in Crop Research Institute, Fumesua-Kumasi, Ghana to screen 20 groundnut varieties for leaf spots resistance using both molecular and phenotypic tools. Differences in disease incidence among individual plants, severity score, lesion diameter and defoliation across the 20 genotypes were highly significant (p more...

This experiment was carried out to determine the genotypic variation among rice (Oryza sativa) accessions using simple sequence repeats (SSR) markers. In the present study, a total of 12 SSR markers were used across 87 rice accessions from six countries. NTSYS-pc and PowerMarker software were used for data analysis. Six primers out of these 12 primers showed DNA amplification and polymorphism among the 87 rice accessions. The number of alleles detected by these six primers ranged from 2 to 9 with an average of 6.83 while polymorphism information content (PIC) ranged from 0.34 to 0.79 with an average of 0.55. The unweighted pair group method with arithmetic averages (UPGMA) cluster dendrogram generated based on the six SSR markers grouped the accessions into 4 clusters with 41% similarity coefficient. Accessions from these four clusters have late maturity, green basal leaf sheath colour, no awn and fewer tillers, respectively. This experiment has proven that even a small number of SSR markers are effective in assessing genetic diversity in rice. The genetic diversity revealed by the SSR markers in this study would be very important to select potentially good genotypes for future rice improvement programmes. Key words: Dendrogram, genetic diversity, molecular markers, rice. more...

Jute mallow rich in proteins, vitamins and essential amino acids is an important leafy vegetable in Africa. Ethno-botanical knowledge on the crop in Ghana has been only incompletely documented and little is known about variation and diversity of local accessions. In order to document available ethnobotanical knowledge and investigate diversity of local accessions, 4000 farmers in twenty districts were surveyed using participatory rapid appraisal tools and techniques. 50 accessions of local germplasm were collected from these districts. Using randomized complete block design with three replications, the 50 accessions collected were characterized based on 12 quantitative and 6 qualitative traits. Results of the survey recorded several vernacular names of the crop and their meaning referring to the slimy nature of the leaves. Some local cultivars which were known in the past are no longer cultivated in farmers’ field suggesting genetic erosion of jute mallow in Ghana. Apart from food, respondents use jute mallow to treat fever, waist pain, stomach problems and loss of appetite indicating nutraceutical potential of the crop. Hierarchical cluster analysis grouped the accessions into four distinct clusters and individuals from the same geographical origin were separately classified. Quantitative traits such as leaf length, number of branches per plant, and number of leaves/plant defined the first principal component. Accessions Cagric 26, Cagric 28, Cagric 41, Cagric 08 and Cagric 01 recorded high yields. These accessions could serve as parents for breeding of improved cultivars. more...

African locust bean is an important non-timber leguminous tree species for food security in Sahelian zones of Africa. Despite its multipurpose uses by local inhabitants, not much is known about its nutritional importance and ethnobotany in Ghana. For this, one thousand farmers randomly selected from five towns in the transitional zone of Ghana were surveyed using participatory rapid appraisal tools and techniques. The major uses of the plant in the survey area include food, medicine and firewood. Men are involved in the collection of the fruits and women process the seed into “dawadawa”, a protein rich condiment. Folk names of the plant in the study area means a mother or helper indicating the importance of the plant in nutrition and food security. The leaf, bark, root and fruit of the plant are used to treat various medical problems including fever, diarrhoea, stomach problems, boils and burns. Bad odour, limited market access, lack of elite genotypes, bush fires and tedious labour operations were the main constraints of African locust bean production in Ghana. Results on the stages of domestication show that African locust bean is in early stages of domestication which suggest that the respondents are aware of the food value and have a sense of ownership of the crop. Proximate composition of the pulp and the dehulled seed was determined using the official method of the Association of Official Analytical Chemists revealed that the pulp contains 2.47 % ash, 2.15 % protein, 1.33 % fat, 6.9 % fibre and 74 % carbohydrates. The dehulled bean contains 3.91 % ash, 20.93 % protein, 26.33 % fat, 4.92 % fibre and 34.18 % carbohydrates. These findings justified urgent need to domesticate, conserve natural populations and to develop improved varieties to ensure food and nutrition security and health in Africa. more...

Groundnut rosette disease is one of the most damaging diseases militating against groundnut production in sub-Saharan Africa. The disease cause up to 100% yield loss whenever epidemic occurs. The most effective, economic and environmental friendly method to control the disease is through genetic resistance. Knowledge on inheritance of resistance to the rosette disease is required to accelerate breeding of resistant varieties. A study was conducted to understand the nature and magnitude of gene effect of resistance to the disease. Thus F1, RF1, F2, RF2, BC1, RBC1, BC2, and RBC2 progenies were derived from crosses of Otuhia × Manipintar, Otuhia × Shitaochi, ICGV 01276 × Manipintar, and ICGV 01276 × Shitaochi along with their parents were evaluated in a randomized complete block design at CSIR - CRI, Fumesua, under artificial infection. Generation mean analysis revealed that additive gene action effect was predominant on the resistance to the disease in all the crosses. Additive by dominance was the only form of non-allelic interaction observed to be significant in ICGV 01276 × Manipintar cross. Reciprocal differences suggested the presence of maternal effect involved in the inheritance of resistance to groundnut rosette disease. Estimates of broad and narrow sense heritability indicated that genetic effect was larger than the environmental effects in this study. Disease diagnosis using TAS ELISA revealed the presence of groundnut rosette assistor virus (GRAV) antigens in the resistant samples analyzed. Resistant genotypes containing GRAV were considered to be resistant to the GRV and its Sat-RNA, but not the GRAV which causes no obvious symptoms by itself. Pure line breeding with selection from early generation is suggested for the improvement of resistance to rosette virus disease, because additive genetic effect contributed significantly in controlling the inheritance of resistance to groundnut rosette disease (GRD). Key words: Additive, dominance, heritability, inheritance, heterosis, rosette disease. more...

The objective of the study was to assess the yield stability performance of taro genotypes evaluated in three environments. Twenty – five genotypes (five parents and twenty F1 hybrids) were evaluated in Dormah Ahenkro in the Bono region, Bunso in the Eastern Region and Tano Dumasi in the Ashanti Region of Ghana from April–December 2019. The experiment was laid out in RCBD with three replications in each location with 6 plants per plot at a planting distance of 50 cm × 100 cm for inter and intra planting distances respectively. Data was collected on yield and yield components in all the locations. The results showed significant difference (p × BL/SM/115, BL/SM/10 × CE/MA/32, BL/SM/115 × CE/MAL/32, BL/SM/10, CE/IND/16 and BL/SM/10 × KAO19 were found to be high yielding and stable across the environments. Genotype BL/SM/10 × BL/SM/115 was however identified as the ideal genotype with high yield and wider adaptability and should be evaluated on farmers’ field and onward release to farmers. The GGE biplot also identified Tano Dumasi was the most ideal environment for the evaluation of taro genotypes for yield and yield components. more...

Corms of eighteen (18) genotypes comprising twelve (12) introduced and six (6) local genotypes were studied for their nutrient quality to provide information on their nutrient characteristics for a holistic development of the crop. The crop is known for its edible corms and leaves. Corms are boiled before eating and take a short time to cook as their carbohydrate structure is not complex. The leaves are eaten as vegetables. The crops were planted at Nobewam in the Ejisu-Juaben Municipality in the Ashanti Region of Ghana using the Randomized Complete Block Design (RCBD). The biochemical or nutritional analysis was done at Crop and Soil Sciences laboratory at Kwame Nkrumah University of Science and Technology (KNUST). Data were collected on the chemical and mineral compositions of the genotypes (corms). Variations were observed in both chemical and mineral characteristics. Carbohydrate content of the genotypes ranged from 62% to 76%; protein ranged from 13% to 25%; fibre ranged from 1% to 2%; calcium ranged from 0.29% to 0.72% and iron content ranged from 0.18 mg/100 g to 1.18 mg/100 g. Significant differences P<0.05 were observed in both chemical and mineral traits, indicating a higher degree of variability in the genotypes. Significant P<0.01 and positive correlations were observed between protein and energy levels; magnesium and iron; magnesium and calcium; and potassium and ash. The Principal Component Analysis (PCA) showed that the first component (PC1) accounted for 96% of variation. Some genotypes including; BL/SM/10, BL/SM/132, KA/019, SAO/020, BL/SM/151, BL/SM/80, BL/SM/116, BL/SM/16, and KA/035 possess desirable nutrient levels such as protein, fibre, carbohydrate, and iron which could be exploited for further development of taro in Ghana. more...

Neglected and underutilized crop species (NUS) are important genetic resources for nutrition, food security, medicine, management of agricultural risk and income generation for rural communities in Ghana. Little is known about their diversity, farmers’ management practices and safety of NUS conserved on-farm while these are prerequisites for developing strategic action plans to ensure their conservation and thus their continued utilization. This study was designed to (1) assess the diversity, forms of consumption and management practices of NUS in Ghana, (2) investigate constraints of on-farm conservation of NUS and the linkage between cultural practices in traditional farming systems and the safety of the NUS conserved on-farm in Ghana. A survey involving 1800 respondents was carried out in nine (9) farming villages of Ghana using participatory research appraisal tools. Seventy-two NUS species were identified on farmers’ field. The grouping of these species into major commodity crops suggests high diversity of NUS genetic resources in Ghana which could be used to further enhance nutrition and food security. The high market value of some of the NUS species suggest that they are well known and consumed. Mass use of systemic weedicides by farmers, activities of herdsmen and lack of knowledge on conservation of seeds and tubers are the main factors reported by farmers as the cause of genetic erosion of NUS on their farms. These findings create an urgency to collect and conserve genetic resources of NUS in Ghana to promote their utilization and breeding of improved varieties. more...

Maize (Zea mays L.) is the most important cereal crop produced in Ghana. However, yield of the crop is generally low, producing just about 1.7 t/ha. The low yield is attributed to continuous use of local/unimproved varieties. Generally, hybrid varieties have proven to out-yield the local/unimproved varieties due to improved vigour. Development of hybrid varieties depend on good understanding of combining ability and inheritance of important quantitative traits such as grain yield (GY). 45 half-diallel crosses generated from 10 extra-early maturing yellow inbred lines were evaluated in 2015 under rain-fed conditions. The objectives were to determine the genetic control, breeding value and estimate heritability for GY and agronomic traits of the inbred lines under contrasting growing environments in Ghana. General combining ability (GCA) and specific combining ability (SCA) were important in the inheritance of GY and agronomic traits of the inbred lines. However, GCA was more important than SCA across environments to suggest that additive gene action was more important than non-additive gene action in the inheritance of GY and agronomic traits in the inbred lines. High broad-sense heritability, for GY and other agronomic traits indicated preponderance of additive gene action in trait expression, thus, selection based on phenotypic expression could be feasible. Inbred lines P1, P4 and P8 were good combiners for high GY. The genotype, P4 × P8, was identified as the ideal and most yielding single-cross hybrid across research environments and should be further tested on-farm before commercialization. more...

Stem canker caused by Phytophthora palmivora and Phytophthora megakarya is a serious disease of cacao (Theobroma cacao L.). Studies of the genetics of resistance to this disease is important to identify an effective procedure to use in breeding resistant varieties. The objective of this study was to determine mode of inheritance, combining ability and heritability of resistance to stem canker in cacao. A 6 × 6 full diallel mating design was used to generate 36 F1 hybrids which were evaluated for resistance to stem canker with three replications under artificial inoculation with 1 mm2 agar plug taken from actively growing colonies of 10-day old cultures of P. palmivora and P. megakarya. Twelve months later, the canker lesions on outer bark of the stem of the seedlings were measured and the canker lesions inside was also measured after scraping the bark. There were significant (p 50%) of GCA suggest that additive gene effects were more important than non-additive gene effects. The overall direction of results showed that using one of the following parents: P1 (Alpha B36), P4 (T17/524) and P5 (T65/238) as the female produced progenies with better resistance to stem canker disease than when they were used as the male parent. The majority reflected the resistance level of the female parent, suggesting that resistance to stem canker in cacao is influenced by maternal inheritance. Cacao genotypes Alpha B36, T17/524 and T65/238 showed significant negative GCA effects for resistance to stem canker suggesting that these genotypes will transmit the trait to their progenies and therefore recommended for cacao breeding. Narrow sense heritability for stem canker resistance was low indicating large component of dominance effects and influence of environment in inheritance of resistance to stem canker in cacao. However, the very high broad sense heritability (0.99) coupled with large variation within the cacao tree population indicate that progeny testing and within family selection would be appropriate in breeding against stem canker in cacao. more...

Studies on quantitative genetics of foliar resistance to black pod disease in cacao could inadvertently use cocoa swollen shoot virus (CSSV) infected leaves which could bias the results especially in West Africa where the virus is prevalent. However, effects of CSSV on inheritance and heritability of foliar resistance to Phytophthora species is not known. Choice of an efficient breeding method requires an accurate estimation of genetic effects in selection schemes for foliar resistance to Phytophthora species in cacao. The objective of this study was to investigate the effect of CSSV infection on quantitative genetic parameters of foliar resistance to cocoa black pod disease in a population of 36 F1 hybrids developed by mating six cacao genotypes using a diallel method. The generated F1s and their parents were evaluated for foliar resistance to P. palmivora and P. megakarya using a randomized complete block design (RCBD) with three replications. 1A CSSV and Nsaba CSSV strains were used to infect the cacao genotypes using the patch graft method. The parents chosen showed significant variations for scores of leaf discs after inoculation with P. palmivora and P. megakarya. The leaf disc scores of CSSV infected crosses were lower than leaf disc scores of CSSV-free crosses. Genetic component analysis showed that the effects of GCA and SCA was significant for both CSSV-free and CSSV-infected crosses in resistance to P. palmivora and P. megakarya. The significant GCA and SCA for both CSSV-free and CSSV-infected crosses strongly suggest that both additive and non-additive genetic effects play an important role in the determination of inheritance of foliar resistance to Phytophthora species in cacao. There was significant variability in mean squares of GCA and SCA of CSSV-free and CSSV-infected crosses indicating that CSSV infection modifies GCA and SCA of affected plants. Narrow sense heritability was relatively low (0.31) for foliar resistance to P. palmivora and P. megakarya under CSSV-free and 1A CSSV strain infected conditions. However, heritability for foliar resistance to P. palmivora (0.43) and P. megakarya (0.36) was significantly higher under Nsaba CSSV infected condition. The modifications of mean squares of GCA and SCA and narrow sense heritability due to CSSV infection could mislead in choice of breeding methods indicating that attention must be paid to the infection status of plants when conducting quantitative genetics studies using diseased and healthy plants. CSSV status of leaf samples should be known before using them in leaf disc test. Genotypes Pa7/808 and Pound 7 had high negative GCA effects and are promising parents for enhancement of resistance to black pod disease in cacao. more...

Gboma eggplant ( Solanum macrocapon L.) of the family Solanaceae is an important fruit and leafy indigenous vegetable in Africa. Despite the numerous nutritional, medicinal and economic benefits derived from the crop, little is known about the genetic parameters governing the inheritance and combining ability of the yield components. Thus, a study was conducted to investigate genetic information on the relevant yield components of the crop. Results showed significant mean squares for General Combining Ability, Specific Combining Ability effects for number of leaves per plant, fruit width and plant height, indicating the combining effect of additive, non-additive and maternal effects for expression for those traits. Conversely, significant (P< 0.05) SCA effects for number of branches per plant, leaf length, leaf width and fresh leaf weight indicated the preponderance of non-additive gene effect. GCA/SCA ratios for the various traits indicated that the relative contribution of additive to non-additive effects varied widely from trait to trait. Significant reciprocal effects for most of the traits were an indication that cytoplasmic or maternal gene effects played a major role in modifying the inheritance of the yield parameters, and that the choice of the maternal parent is relevant in breeding for these traits. Estimated GCA effect among the parents revealed that CAGRIC 03 has a breeding value for number of branches, plant height, fruit length, leaf length and fresh leaf weight, which makes it a valuable material for development of improved varieties. CAGRIC 01 was the promising combiner to increase fruit weight and number of leaves per plant. Hybrid P1xP2 was the best specific combiner to increase fruit width, leaf width and fruit width. High heritability estimates for most of the traits indicate that genetic variation was higher than the environmental variation in the study. Keywords: African eggplant, heritability, Solanum macrocapon more...