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An experiment was conducted to find out the effects of some pre-germination seed treatments on germination of mango (Mangifera indica L.) seeds and initial growth of mango. Seeds obtained from a local mango variety at Nyankpala were sown in polyethylene bags filled with topsoil for the experiment. The four treatments used were; seeds sown without seed coats (SW), seeds without seed coats soaked in cool water of 5ºC for 12 hours before sowing (SSC), seeds without seed coats soaked in warm water of 15ºC for one minute before sowing (SSW) and seeds with seed coats sown to serve as the control (SC). Randomized Complete Block Design was used and each treatment was replicated three times. The parameters measured were germination percentage, height of seedlings, leaf length of seedlings, number of leaves and stem diameter of seedlings. Data obtained were analyzed using Analysis of Variance and the differences were determined by using Tukey-Kramer multiple comparison test. All the treated seeds recorded more than 80% of germination three weeks after sowing, with SSW recording the highest value of 91%. In general, the treated seeds performed significantly (p < 0.05) better than the control for the parameters studied. SSW is recommended for adoption since it performed optimally better than the other treatments in terms of number of leaves (7.67), leaf length (14.71 cm), leaf width (4.41 cm), stem diameter (1.82 cm) and plant height 20.86 cm).

Two proposed containers (50 kg-polypropylene sack and 50 kg-wooden crate) were compared with existing packaging containers (100 kg-polypropylene and jute sacks) to transport sweetpotato storage roots from major aggregation sites to distant urban market centers. The extent of breaks, bruises and the impacts, incurred by storage roots packaged in the different containers, were assessed. Additionally, at the urban market centers, the visual quality of the transported storage roots was evaluated by both aggregators and consumers. The benefit cost ratio (BCR) for each of packaging options was calculated to ascertain their profitability for sweetpotato roots transportation. The existing polypropylene/jute sacks resulted in significant major breakages in both years (p = 0.028, 0.016) after transportation for the Afram Plains-Accra route in truck. The donkey-driven carts or tricycles used for the Bawku-Bitou route did not show any significant (p > 0.05) influence on the storage roots contained in the existing polypropylene/jute sacks. The average impact recorded at both loading and offloading sites was significantly different (13.4 - 19.3 g vs. 0 - 30.0 g; p = 0.045) for all the containers. The proposed 50 kg-woodencrate had a significantly superior (mean rank of 127; p < 0.0001) visual quality compared with the other packages. All the packaging options showed profitability, because they had a BCR > 1.40, except for the 50 kg-wooden-crate. The 50 kg-polypropylene container delivered better quality roots to urban market centers than the existing packaging containers, and was more profitable than the 50 kg-wooden crates. The 50 kg-polypropylene container is recommended for the transport of sweetpotato storage roots in Ghana.

The research was conducted to establish the effects of triple super phosphate and rhizobia inoculant on yield of soybean (Glycine Max (L)) seed quality in the Northern region of Ghana. Multi-locational trials were adopted and three different locations were used. Soybean foundation seeds obtained from Savannah Agriculture Research Institute were subjected to three different treatments on the field. These treatments were TSP + Inoculant, TSP only, Inoculant only and a control plot as a check. Randomize complete block design was used to allocate the treatments to the various plots. Data collected from the field included: number of days from seeding to germination, flowering and pod formation; nodule formation; plant height, number of pods per plant per treatment (Pod load), number of days to maturity, seed weight at harvest per plant per treatment (1000 seed weight) and finally, the yield was determined after harvest. Results revealed that the treatments (TSP + Inoculant, TSP only and Inoculant only) generally enhanced growth, development and yield of soybean seed as compared to the control plots in almost all the locations. The application of Rhizobia inoculant contributed significantly to the development of the soybean plant. It aided the fixation of atmospheric nitrogen into the soil which improved its fertility that led to the significant increase in the number of nodules that were formed by the plant. The pod load was very high for all the treated plots. They were fully filled with seeds which were evidence in the yield obtained from the trials. TSP in combination with inoculants gave a very good yield of 2.66 Mt/ha and was significantly higher than all the other treatments. This result is a clear indication of how phosphorus fertilizer and inoculant positively affected the yield. Seed producers should be encouraged, in addition to good agronomic practices, to apply the recommended dosage of inoculant and TSP to their seeds and soybean fields respectively. This would lead to early maturity and high yields. Keywords: Soybean seed, Northern region of Ghana, Phosphorus, Inoculant, Yield

An experiment was carried out to study the sensitivity of amaranthus to different sources of soil nutrients and different amounts of irrigation water at different temperatures. Nitrogen (N) rich materials (compost/poultry manure) and carbon (C) rich material (biochar) used included poultry manure + rice husk biochar (PM+RB), poultry manure + sawdust biochar (PM+SB), rice husk compost + rice husk biochar (RC+RB), sawdust compost + sawdust biochar (SC+SB) mixed at 10 ton ha-1 N rich material to 5 ton ha-1 C rich material. Rice husk compost only, Sawdust compost only (at 10 ton ha-1 for each of RC and SC), NPK (400 kg ha-1) and no amendments as Control were also used. Two irrigation amounts (0.1124 mm and 0.225 mm per pot), were imposed resulting in 12 treatment combinations, in a completely randomized design with 4 replicates. The experiment was repeated under two different temperatures of 37 and 30°C in the glass house and pot house, respectively. Data on growth, yield, water use and nutrient leaching were collected. PM+RB produced the tallest plants (31.67 cm) with 0.1124 mm irrigation at 30°C. PM+SB treated plants had more leaves (17) with 0.1124 mm amount of irrigation water at 37°C. NPK treated plants gave the highest stem girth (5.87 cm) and highest SPAD value (42.5%) with 0.1124 mm amount of irrigation water at 37°C. Leaf area index was highest (43) at 30°C for plants receiving NPK and 0.225 mm amount of irrigation water. NPK treated plants gave the highest fresh biomass of 36.93 g at 30°C but lowest biomass (13.01 g) at 37°C. PM+SB gave the highest fresh biomass weight of 16.7 g at 37°C and highest volume of leachate (123 ml) with 0.225 mm irrigation water at 30°C. At 37°C, SC gave the highest leachate volume (166 ml). The study indicates a good potential for sustaining crop yield with organic materials under increasing temperature and declining water resources that may be associated with changing climate. Key words: Amaranthus, compost, biochar, climate change, irrigation frequency.

Experiments were carried out in the laboratory with the aim of accessing the effectiveness and parasitism by Trichogramma evanescens to prevent Corcyra cephalonica from infesting rice in paper and jute bags. Eight small jute or paper bags filled with 5 kg of organic rice grains were prepared and the openings sealed. Sentinel egg cards were prepared with thirty fresh eggs of C. cephalonica glued onto small pieces of paper cardboard. Eight sentinel egg cards were introduced into a plastic box measuring 60 × 40 × 21 cm, i.e four cards on top surface of the bag and the box bottom, respectively. Approximately 500 adults of T. evanescens were released 10–30 cm away from the egg cards. The control boxes contained no parasitoids; there were five replicates for all treatments and controls. Two experimental conditions were tested, i) placing a single T. evanescens-release unit with sentinel egg cards placed every 3–4 days without any further replacement of the release unit for three weeks, ii) both new host eggs and T. evanescens release units were replaced every 3–4 days. Mean emergence of C. cephalonica was significantly (p > 0.001) suppressed by the release of T. evanescens. There was statistically no significant difference on the number of emerged moths on paper bag compared to jute bag. All sentinel egg patches were visited by T. evanescens. There was no correlation between the distance (10–30 cm) at which the sentinel egg cards were placed away from the T. evanescens release point and the number of parasitized C. cephalonica eggs. There was no decrease in parasitism over time. The results demonstrate that T. evanescens has the potential for host-location ability and parasitism of C. cephalonica both on paper and jute bags. This parasitoid could be a promising candidate for the biological control of moth pests in bagged stored products.

An experiment (Completely Randomized Design) was set up to determine the effects of Clay Pot Sub-surface Irrigation (CPSI) and spacing on the growth and fresh weight of lettuce (Lactuca sativa). The treatments were: CPSI with spacing; 15 x 15 cm, 20 x 20 cm and 30 x 30 cm. Control treatments were Watering Can Irrigation (WCI) with the same spacing as above. Treatments were replicated three times given a total of 18 experimental units. Eighteen large enamel basins of 50/20 cm (diameter/height) were filled with good topsoil and a clay pot buried neck deep in each of the basins. Seedlings were planted in all the eighteen basins. Five Hundred mL of wastewater was applied daily to plants in each container having either clay pot or watering can treatment. Plant height increased from 2.50 to 4.25 cm within 6 Weeks after Transplanting (WAT) under CPSI and only increased from 2.14 to 2.99 cm under WCI. The CPSI also supported better leave growth and fresh weight. The fresh weight of lettuce increased almost two fold under 15 x 15 cm spacing compared to 20 x 20 and 30 x 30 cm.

Experiments were conducted to determine whether applying seed vernalisation or gibberellic acid treatment, alone or in combination, can induce flowering in cabbage plants raised from seeds and rato...

The shea tree, Vitellaria paradoxa, is one of the most economically and culturally important indigenous tree species in the Sudano-Sahelian region. Its seeds contain a vegetable fat, internationally known as shea butter, which is widely used in edible, cosmetic and pharmaceutical sectors. Based on samples from 456 trees distributed in 17 locations across the species natural range from Senegal to Uganda, the fatty acid and tocopherol variation, and its relationship with geographic and climatic variables, was assessed in order to address the pattern and the origin of this variation across the natural range. Significant differ- ences between Western and Eastern regions for oleic, stearic acid, saturated-unsaturated acid ratio and c-tocopherol were identified that it is postulated maybe a result of genetic drift due to the evolutionary history of shea tree populations. Within regions the difference among stands was significant for most constituents; however the major part of the variation was observed among trees within stand (53-90 %). Relationships with climatic variables were not veri- fied, weakening evidence for clinal variation hypoth- eses suggested by previous studies.

An assessment of soil physical and chemical properties was carried out in Shea parklands of northern Ghana, selected along a North-south climatic gradient in 2011. The study sites were Paga, Nyankpala and Kawampe, which are located in the transitional and Guinea savannah zones of Ghana. For each site, 9 fallows and 9 cultivated fields were used, a total of 18 plots per site. Soil samples were collected at a depth of 0 to 30 cm and analysed for particle size distribution, pH, organic matter (OM), nitrogen (N), phosphorus (P), exchangeable bases, exchange acidity and effective cation exchange capacity (ECEC). The results revealed that the soils were strongly acid to neutral in reaction. The soils at Nyankpala parkland were comparatively more acidic (pH 80%) and deficiencies of basic cations were uncommon. Land use did not significantly influence the soil chemical properties. However, N values, were significantly higher in old fallows than in respect of new fallows and cultivated fields. Soil particle size distribution especially at Nyankpala was significantly influenced by land use, with fallow lands having more proportion of sand than that of cultivated fields. The extremely low P content (trace – 7.11 mg/Kg) of the soils might be due to P fixation which was commonly reported for soils in northern Ghana. However, if these soils were supplied with N fertilizers, seedling regeneration would be promoted due to the fact that increasing N levels and decreasing P levels in soil, results in significant increase in seedling dry weight as well as increasing uptake of total shoot N and C.

SummaryOsmotic priming of cabbage seeds with polyethylene glycol (PEG 6000), to prevent germination during a vernalising treatment, was investigated as part of a study into potential seed production in the tropics. A preliminary attempt to vernalise cabbage seeds had resulted in weak stemmed seedlings, with fungal infections, as a consequence of the non-primed seeds having germinated while still in the fridge at the low temperatures used for vernalisation (0° – 5°C). Two experiments to determine the effect of PEG 6000 on the viability and vigour of cabbage seed at non-vernalisation and vernalisation temperatures were carried out. In the first experiment, seeds of ten varieties of cabbage were imbibed separately in 302.44 g l–1 PEG 6000 in Petri dishes lined with filter papers moistened with PEG solution, or with distilled water as controls. The primed seeds were kept for 2 weeks at 25°C (non-vernalisation temperature) under an 8 h photoperiod, washed in distilled water and sown immediately into 4 cm-squar...