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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.

Rhizobacteria have huge potential for biocontrol activity against many plant pathogens. Isolation and identification are therefore crucial to understand their microbial diversity and ecological imp...

Sexual incompatibility among kola genotypes accounted for over 50% yield loss. Compatible and high yielding varieties are being searched to develop commercial orchards. The objective of this study was to identify self-compatible and compatible partners of kola genotypes from self, single and double hybrid crosses and assess heterosis pattern in resulting hybrids for sexual compatibility and key nut yield and quality traits. Three field gene banks of kola (JX1, GX1, MX2) and one advanced germplasm (Bunso progeny) of C. nitida in Ghana were then assessed for sexual compatibility, nut yield and nut quality. Data were collected on pod set, pseudo-pod set, pod weight, number of nuts per pod, nut weight, brix, potential alcohol and nut firmness. Crosses resulted in significant (P

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.

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

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).

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

Six generations of eggplants (P1, P2, F1, F2, BC1 and BC2) obtained from two crosses SM001-07 x ST004-03 and SM001-07 x San005-01 were grown in an open field using Randomized complete Block Design with four replications. The experiment was conducted to determine gene effects for the inheritance of twelve nutritional and antioxidant traits in eggplant using generation mean analysis. The analysis of variance showed significant differences for most traits indicating the presence of sufficient variation in the eggplant materials under study. Additive-dominance effect was adequate to demonstrate the genetic variation and its significance in the inheritance of protein and magnesium contents, while non-allelic interactions were observed to be important for iron, zinc and total phenol in both crosses. The study also showed low values for dominance and environmental variances that resulted in high heritability values for most traits. Therefore, to improve these traits population improvement approaches (recurrent selection or pure line) followed by delayed selection in segregating generation would yield better results.

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

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.

Knowledge of combining ability and mode of inheritance is important in devising strategies to breed compatible and high yielding plant varieties. This study determined combining ability and understood the mode of inheritance of sexual compatibility in Cola nitida, a crop in which incompatibility was reported. 10 × 10 complete diallel mating design was used to cross ten (10) elite clones of kola. Data collected included percentage pod set and nut traits of the various crosses. Percentage pod set differed significantly among crosses (p 80% pod set) as compared to crosses between red and pink colour nut genotypes. Both additive and non-additive gene effects were significant (p

The African oil palm (Elaeis guineensis. Jacq.) is an oleaginous tree belonging to the family Arecaceae. The crop is naturally a diploid species (2n = 2x = 32) and the most important oil bearing perennial tree crop cultivated in tropics. In spite of its huge economic importance, it has a very narrow genetic base making its improvement using conventional techniques very difficult. All commercial planting materials are hybrids derived from heterozygous pisifera and dura parents. The imperativeness of generating adequate novel materials with sufficient genetic diversity in order to increase progress in oil palm improvement is therefore, very essential. Genomic manipulations through chromosome doubling may present opportunities to broaden the genetic base and increase the diversity within the commercial oil palm species. Developing an efficient genome doubling protocols using anti-mitotic agents is very important in this respect. It will also complement haploid/doubled haploid production efforts by enabling successful deployment of doubled haploids in oil palm breeding programmes. The objectives of this study were, therefore, to optimize genomic doubling in oil palm by determining optimum colchicine concentrations and also outline procedures for screening for putative polyploids. Oil palm seedlings were subjected to colchicine treatment at concentrations of 0, 1.26, 3.76, 6.26 and 8.76 mM for 0, 3, 6, 12 or 24 hours. The colchicine treatment produced variable physio-morphologies in the treated seedlings. Principal component analysis and agglomerative hierarchical clustering of genotype dependent treatments were carried out to provide an ordination guide. The response of oil palm seedlings to colchicine treatment showed genotypic, concentration of colchicine applied and treatment duration dependency. Ploidy level analysis of the colchicine treated seedlings revealed that polyploidization in oil palm increased significantly (p ≤ 0.05) with increasing colchicine concentration. Seedlings of the genotype G-131 responded more favourably to the colchicine treatment than seedlings of G-132. Optimal colchicine concentration for genome doubling in G-131 (28.9 %) and G-132 (17.8 %) was 8.76 mM applied for a period of 24 h. A population of 154 tetraploids out of 1800 seedlings of the two genotypes mutagenized has been identified and being raised for further evaluation and genetic exploitation.

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.

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.

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

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.

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.

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

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.

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.

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.

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.

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.

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

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

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.

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.

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.

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.

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.

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.