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Cashew (Anacardium occidentale L) is an important cash crop cultivated by about 3 million households in Africa and serves as the livelihood for many African farmers, especially Ghana. Despite the importance of cashew as a commodity crop with increasing cultivation in Northern Ghana, the crop is challenged with problems such as, low and variable nut yields, low kernel out turn percentage and susceptibility to insect pests as a result of establishing cashew farms with unselected seeds. In order to address the challenges, the Cocoa Research Institute of Ghana established a clonal evaluation trial in Northern Ghana (dry savanna vegetation) to indentify promising clones for subsequent distribution to cashew farmers as an interim measure. The trials consisted of ten different clones planted in Randomised Completed Block Design (RCBD) with four replicates. Parameters evaluated were yield, yield efficiency, nut weight, percentage out turn and canopy area. Data analysis was performed with Gen Stat version 11.0 and the results revealed significant differences (P < 0.05) in the performance of the clones in all the parameters considered. Such differences allowed the identification of promising clones over other clones tested. A few clones combined two or three traits (parameters) which were significantly different from the rest of the clones evaluated. No single clone was found to be significantly different from the rest in terms of all the parameters considered. However a greater proportion of the clones were found to produce yields far above average yields recorded by unselected cashew trees in farmers' fields. Clones W266 and W278 seem outstanding for most of the parameters considered, though not exclusive.

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Phenolic compounds have been suggested as one of the defence mechanisms to cocoa swollen shoot virus disease (CSSVD), but not well studied. Correlation and genetic variation of total phenolic content (TPC) and CSSVD resistance among 53 cocoa families were investigated. Threemonth-old seedlings of 15 families obtained from an incomplete 6 9 3 NCII mating design, of 24 families from a 3 9 8 NCII mating design and of 14 other families were evaluated for CSSVD and TPC. Plants were inoculated with viruliferous mealybugs carrying the New Juaben CSSV strain (1A) in a gauze house facility. A single seedling randomization within blocks procedure was followed, using the gauze house units as blocks. There were six blocks with five seedlings of each family randomized within each block. Disease severity scores on leaf flushes at the first, second, third and seventh flushes after inoculation were recorded. The TPC before and 3 months after inoculation was also determined. Family effects were highly significant (P ≤ 0.01) for CSSVD severity scores and TPC. Narrow-and broad-sense heritability estimates were low for CSSVD severity but moderate to high for TPC evaluations. Correlations between severity scores and TPC were weak (r = À0.22 to 0.40) suggesting that the TPC may be of little value in selecting CSSVD resistance varieties in cocoa. Additive effect in terms of significant GCA was important for CSSVD severity scores whereas both additive and nonadditive effects were important for TPC values when the 3 9 8 and 6 9 3 NCII mating designs were analysed. Only clones GU 239/H, GU 290/H and GU 225/V had favourable GCA effects for CSSVD symptom expression indicating their potential for developing progeny with high levels of resistance to CSSVD infection.

Cashew (Anacardium occidentale L.) is an important tropical cash crop cultivated in Ghana. It provides livelihood for about 200,000 people and contributes 6.1% to Ghana&rsquo;s gross domestic product (GDP). Four Brazilian dwarf accessions were introduced to improve nut yield. Objectives of this study were to (1) assess the agronomic performance of the accessions across two contrasting ecologies, (2) determine environmental influence on juvenile growth, (3) determine the relationship between early vegetative growth and yield and (4) explore heritability and genetic advance for the measured agronomic traits. The experiment was laid out in a randomized complete block design with 3 replications. Results revealed significant (p &lt; 0.05) environmental influence on growth and yield of cashew. Transitional savanna agro-ecology is more suitable for cashew growth and development. Crop year, location and crop year &times; location interactions also influenced most of the agronomic traits. Early growth characteristics alone were not enough to predict yield. Genotype B2 ranked highest yielding across the agro-ecologies. Moderate to high heritability and genetic advance estimates were observed for nut yield, plant height and girth, an indication of variability among accessions needed for cashew improvement in Ghana.

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Kola (Cola nitida) is an important economic cash crop for many West and Central African countries. It has several medicinal uses in the pharmaceutical industries and also plays a major role in traditional marriages among Islamic communities across West and Central Africa. The crop is extensively cultivated in Nigeria and Ghana. However, it exhibit signs of total and partial sterility as well as self incompatibility when propagated from seeds in most cases. Therefore, grafting is seen as a method of choice in addressing the problem stated above. Though grafting accounts for some degree of success, there is the need to assess genotypic and physiological factors that account for high or low grafting success. Genetic and physiological factors (such as rootstock age) affecting grafting success and growth in kola (C. nitida) were investigated in two separate experiments. In experiment I720 kola seedlings were raised from unselected kola nuts and sown at two monthly intervals. Four groups of seedlings (180/group) i.e. 6, 8, 10 and 12 months old were thus produced. Three different scions (A1, A12 and JB1) measuring (5 -10 cm) were grafted onto the four age groups of rootstocks, namely, 6, 8, 10 and 12 months. Experiment II consisted of 540 seedlings raised from three main crosses (JX1/9 × JX1/11 * B1/142 × B1/151, JX1/9 × JX1/11 * B2/177 × B2/156 and JX1/9 × JX1/11 * GX1/46 × GX1/53). Grafting was done after six months using the same set of scions as described in experiment I. Experimental design used was 3 × 4 and 3 × 3 factorial designs in completely randomised design with three replicates for experiment I and II respectively. The fixed effects were the different genotype and age of rootstock at grafting whilst the response variable was the percentage of successful grafting two months as well as growth at six monthly intervals. Results from the study showed that grafting onto 6 months old stocks gave the highest percentage success and growth of grafts followed by 8, 10 and 12 months old rootstock in that order in both trial years. The study revealed also a significant rootstock and scion interaction (P < 0.05). We conclude that successful grafting in kola depends on rootstock genotype such as A. M. Dadzie et al. 3874 JX1/9 × JX1/11 * GX1/46 × GX1/53 and has been proven suitable for use in future kola propagation studies. Nonetheless, suitable rootstock with high grafting success does not translate into vigorous scion growth.