Savanna Agro-ecological Zone Of Ghana Research Articles

Quantitative analysis of soil degradation in response to land use change in the Guinea savanna zone of Ghana

Soil degradation (SD) poses a significant challenge to tropical agricultural production systems due to its role in depleting soil nutrients. Recently, SD has threatened population growth by causing hunger and poverty among smallholder farmers in the Guinea savanna agro-ecological zone of Ghana. However, SD cannot be directly measured. Instead, assessment and modelling efforts rely on biological and physico-chemical indicators. This study sought to: (i) select a minimum dataset (MDS) using a multivariate statistical technique; (ii) identify SD processes, and evaluate the extent of degradation; and (iii) suggest strategies to monitor SD in the study area. Soil samples were collected using the Land Degradation Surveillance Framework (LDSF), specifically designed for sub-plot level (1000 m2) sampling. This scheme aligns well with the typical farm structure of smallholder farmers (<10 acres). Soil samples, taken from a depth of 0–20 cm, were analyzed to assess their physico-chemical properties. Principal component analysis (PCA) identified seven key SD processes: soil texture, pH, organic carbon (OC), total nitrogen (TN), available phosphorus (Av. P), base saturation (BS) and Effective Cation Exchange Capacity (ECEC). These identified processes lead to the loss of OC, deterioration of soil texture, reduction in soil nutrients, and increased soil acidity. There was a strong positive correlation (r = 0.70, p<0.05) between soil physical and chemical properties. PC1 explained 26.86% of the total variance, followed by PC2 at 15.31%, PC3 at 12.46%, and PC4 at 9.98%. Also, PC5, PC6, and PC7 accounted for 8.49%, 7.25% and 1.42% of the variance, respectively. The land-use systems we identified significantly affected the concentration of soil nutrients (p<0.001). In our computed Composite Soil Degradation Index (CSDI), CEC emerged as the most significant SD indicator with a weight of 0.328, followed by Si:CL ratio at 0.187. The results indicate that soil management activities should focus on increasing organic matter. Soil nutrient depletion primarily occurs through several processes. Land clearing and burning of organic materials during land preparation are primary causes. Furthermore, a total crop removal during harvest, inadequate manure application, and subsequent leaching and erosion aggravates SD, leading to nutrient-depleted soils. We conclude that the loss of nutrients, specifically CEC, OC, Ex. K and Av. P is the primary contributor to chemical SD. Therefore, implementing integrated soil fertility management (ISFM) strategies, such as applying organic (e.g., animal-based manures, green manure, crop residues, compost) and inorganic fertilizers (e.g., NPK + micronutrients) is crucial for increasing soil nutrient availability, enhancing SOM content, and promoting carbon sequestration in these farming systems. This study establishes a baseline for comparing and evaluating the effectiveness of land management interventions at the landscape level in northern Ghana. Consequently, soil nutrient management should be tailored to site-specific conditions, focusing on increasing the efficiency of N, P, K and micronutrient uptake by plants. Adopting such site-specific management strategies could significantly contribute to the sustainable intensification of agricultural production systems in the Guinea Savanna agro-ecological zone of Ghana.

Quality of seed lots of soybean [Glycine max (L.) Merrill] genotypes produced in a guinea savanna agroecology of Ghana

Crop yield is a derivative of the number of plants harvested. In Ghana, soybean fields are mostly sparsely populated with less than the optimum number of plants, a phenomenon that contributes to poor yields of only 46% of the crop’s potential in farmers’ fields. The low plant population could be the result of the poor quality of the seed planted. Meanwhile, the quality of seed is determined by crop production practices, the environmental conditions of the mother plant, and postharvest handling technologies used. Over 90% of the country’s soybean seed comes from the northern part of Ghana, predominantly the Guinea Savannah. In this study, seed lots of soybean genotypes produced within the Savanna Agroecological Zone of Ghana, were evaluated for physical and physiological traits, and the prevalence of seed borne fungi. Results showed that seed lots produced within the zone and stored under ambient conditions have medium-sized (100 to 140 g/1000 seeds) seeds with an average seed weight of 133 g/1000 seeds. The seed lots evaluated had physical purity values higher than the minimum certification standard of 98% for soybean seed in Ghana. Wrinkled seeds were the most dominant component of the seed with visual defects followed closely by seeds that were discoloured, cracked, and those with purple stains. Aspergillus flavus, Aspergillus niger, Chaetomium globosum, Rhizopus sp and Macrophomina phaseolina were the main fungi identified. Furthermore, the seed lots had an average germination percentage of 86%, which is within the acceptable minimum certification standards for soybean seed in Ghana. Though germination and vigour were variable among the seed lots tested, these parameters were not affected by the presence of the fungi species identified and the amount of seed with visual defects. The findings of this study strongly suggest that the low plant density and the resultant poor yields of soybean usually recorded in farmers’ fields in Ghana are likely due to suboptimal seeding rates at planting coupled with the low use of good agronomic practices with only a small fraction attributable to poor seed quality. Key words: Soybean, Ghana, fungi, savanna agroecology, viability, vigour, shrivelled seeds, germination

Biochar for Wastewater Treatment and Soil Improvement in Irrigated Urban Agriculture: Single and Combined Effects on Crop Yields and Soil Fertility

This work evaluated the agronomic and soil fertility effects of using municipal wastewater or anaerobically treated wastewater for irrigation and applying biochar to a soil from the Guinea savanna agroecological zone of Ghana. For this purpose, untreated municipal wastewater (WW), the effluent of an anaerobic wastewater filtration system (TWW), and clean water (CW) were used as irrigation water in a pot trial. Additionally, rice-husk biochar in the form of raw biochar (RB), water-washed biochar (WB), and biochar used as wastewater filter material (FB) were added to the soil, testing the influence on soil fertility and crop yield. Lettuce and carrot were selected for the pot study, grown on soil mixed with the biochar types at 20 t ha−1 and irrigated with either WW, TWW, or CW. Our results indicated higher crop growth morphology and yields (up to 90% increase) by WW and TWW than CW. The average yield of carrot (34.1 g pot−1) and lettuce (29.3 g pot−1) with TWW irrigation were the highest, followed by 31.2 and 27 g pot−1 with WW, then the lowest yields of 21.7 and 19.5 g pot−1 of carrot and lettuce irrigated with CW respectively. Compared to WW, TWW was more beneficial to plant development, causing an up to 10% increase in crop yields. Soils with FB and WB produced similar agronomic effects and plant nutrient concentrations but were lower than pots amended with RB. Nevertheless, combining RB with TWW showed increasing effects on pH, CEC, and P availability in the highly weathered acidic soil. The results suggest a beneficial effect of biochar-filtered wastewater on soil fertility and crop growth, offering the potential to enhance resource use efficiency in irrigated urban agroecosystems.

English

The adoption of new and high yielding pearl millet (Pennisetum glaucum (L.) R. Br.) varieties can be boosted if they correspond to farmers&rsquo; preferences and answer the constraints prevailing in the production environments. Therefore, the focus of this study was to assess production constraints, farmers&rsquo; preferences and choices of varieties among pearl millet cultivating farmers using participatory rural appraisal (PRA) in the guinea savanna agro-ecological zone of Ghana where the crop is grown. Data collection was through mixed methods of focus group discussion (FGD) and individual interviews with 295 (45 for FGD and 250 for individual interviews) farmers covering 45 communities. Results indicated that the major constraints of production included low yields, bird damage, poor soils, erratic rainfall, downy mildew disease, head insects, and early maturity. Majority of pearl millet farmers depend on own seed source due to lack of access to and low knowledge of improved seeds. Breeding for high grain yield, earliness, resistance to downy mildew disease and bird attack varieties were the leading traits of preference that research should focus on. It is therefore anticipated that breeding program would integrate the product profiling proposed in this work for enhance adoption of new pearl millet varieties in Ghana. &nbsp; Key words: Participatory rural appraisal, constraint, pearl millet Guinea savanna, Ghana.

Pigeon pea (Cajanus cajan) fodder cutting management in the Guinea Savanna Agro-Ecological Zone of Ghana

This study evaluated the effect of cutting regime on biomass yield and nutrient composition of pigeon pea (Cajanus cajan (L) Millsp.) fodder in the Guinea Savanna Agro-Ecological Zone of Ghana. Three cutting regimes (12, 16 and 20 Week After Planting [WAP]) in RCBD were imposed on Cajanus cajan at both initial establishment and regrowth. At each harvest, biomass yield was estimated after which samples of the fodder were separated into leaf and stem botanical fractions for chemical composition and in vitro digestibility. Cutting regime significantly affected plant height, number of branches and stem diameter in both the initial establishment and regrowth. Biomass yield was significantly affected by cutting regime in the initial establishment but not the regrowth. The biomass yield was highest in the harvest at 20WAP (6515kgDM/ha) while 12WAP (3175 kg/ha) recorded the lowest biomass yield in the initial establishment. All chemical composition parameters were significantly affected by cutting regime and botanical fractions except hemicellulose in the initial establishment. Cutting regime also significantly affected DM, CP and ash concentrations in the regrowth with botanical fraction significantly (P < 0.05) influencing CP, NDF, ADF and ash. The highest CP was obtained in the leaf fraction harvested at 12 WAP and 20 WAP in the initial establishment and regrowth respectively. Cutting regime, botanical fraction and their interaction were significant in gas produced at 24 h, SCFA and ME in both the initial establishment and regrowth stages. In conclusion, harvest at 20WAP produced the highest biomass yield but lower CP in the initial establishment whiles in the regrowth, harvest at 20WAP produced higher biomass yield, CP and ME.

Stimulus of nitrogen fertilizers and soil characteristics on maize yield and nitrous oxide emission from Ferric Luvisol in the Guinea Savanna agro-ecological zone of Ghana

Abstract Farmers in Ghana rely on different forms of fertilizers to increase crop yields. The quantity of applied mineral N fertilizer is lost through nitrification and denitrification in the form of the powerful greenhouse gas nitrous oxide (N2O) has not been determined in the field until now. This study was conducted on a Ferric Luvisol in the Tolon District in Northern Ghana to determine the influence of nitrogen fertilizers, soil moisture and soil temperature on N2O emissions and grain yield. Three different nitrogenous fertilizers, i.e. ammonia sulfate (AS), urea (U) and NPK 60–40–40, were applied at either 60 or 120 kg N ha−1 yr−1 to maize, termed AS 60, AS 120, U 60, U 120 and NPK 60–40–40 thereafter. A control was left without N application. The results showed that N fertilizer type and quantities applied affected N2O emissions significantly. Plots of NPK 60–40–40, AS 60 and U 60 emitted 1.22, 1.45 and 1.79 kg N2O N ha−1, respectively, throughout the sampling period and were not considerably higher than N2O emissions from the control plots, which amounted to 0.32 kg N2O N ha−1. In contrast, the N2O emissions of U 120 and AS 120 were significantly higher than the controls, with values of 4.29 and 3.49 kg N2O N ha−1, respectively. When N2O flux was related to grain yield, 1.24 and 1.04 g N2O kg−1 grain was emitted from AS 120 and U 120, respectively. Plots treated with NPK 60–40–40, AS 60 and U 60 produced 0.39, 0.47 and 0.55 g N2O kg−1 grain, respectively, whereas plots without fertilization emitted 0.53 g N2O kg−1 grain. Average N-induced N2O emission factors ranged between 0.10% and 0.22%, with an overall emission factor of 0.15%.

Genetic Studies of Morphological and Physiological Traits Associated with Drought and Striga hermonthica (Del.) Benth Tolerance in Maize (Zea mays L.) in the Guinea Savanna Agro-ecological Zone of Ghana

Genetic Studies of Morphological and Physiological Traits Associated with Drought and Striga hermonthica (Del.) Benth Tolerance in Maize (Zea mays L.) in the Guinea Savanna Agro-ecological Zone of Ghana

Nitrogen Use Efficiency and Maize Productivity in the Guinea Savanna Agro-ecological Zone of Ghana

Nitrogen Use Efficiency and Maize Productivity in the Guinea Savanna Agro-ecological Zone of Ghana

Nodulation and Biomass Yield Response of Cowpea to Row Spacing and Phosphorus Fertilizer Application in the Guinea Savanna Agro-Ecological Zone of Ghana

Phosphorus fertilizer application and planting distance play a major role in the production of shoot, root and nodule dry biomass of cowpea. However, phosphorus is a major limiting nutrient in soils in Ghana. Selection of cowpea varieties that produce good biomass yield under low soil phosphorus or those with high phosphorus response efficiency can be a low input approach in solving this problem in Ghana. Two-season experiments were conducted to evaluate the influence of phosphorus (P) fertilizer and row spacing on growth, nodulation and biomass yield in cowpea. Each of the two experiments comprised of 16 treatment combinations of 4 cowpea varieties, 2 levels of row spacing and 2 levels of P 2 O 5 application laid out in a 4t2t2 factorial experiments in RCBD with four replications. The cowpea varieties were IT t P 148, Valenga, Bengkpla and DPC. The levels of row spacing were 60t20 cm and 40t20 cm, whilst the levels of P were 0 and 30 kg ha -1 P 2 O 5 . The study revealed that varieties DPC and Valenga performed relatively better with respect to shoot and root dry biomass production, number of nodules produced and nodule dry biomass production across both levels of row spacing and phosphorus fertilizer application. The study further established that row spacing of 60t40 cm and P level of 30 kg ha -1 also produced significantly higher quantities of shoot and root dry biomass, number of nodules and nodule dry biomass as compared to row spacing of 40t20 cm and P level of 0 kg ha -1 . For the purpose of producing leguminous fodder crops for feeding livestock, varieties DPC and Valenga should be cultivated for improved animal nutrition. Row spacing of 60t40 cm and phosphorus fertilizer application level of 30 kg ha -1 should also be used for increased biomass yield.

Carbon Dioxide Emission from Ferric Luvisols: The Role of Mineral Nitrogen Fertilizers and Soil Temperature in the Guinea Savanna Agro-ecological Zone of Ghana

Authors' contributions This work was carried out in collaboration between both authors. Author WKA wrote the protocol, designed the study, managed the analyses of the study and performed the statistical analysis and wrote the first draft of the manuscript. Author PKK reviewed the experimental design and all drafts of the manuscript and approved. Both authors read and approved the final manuscript. ABSTRACT Soils in the Guinea Savanna Agro-ecological zone of Ghana are inherently low in fertility, especially nitrogen. Furthermore, organic matter is very low as a result of total removal of crop residue followed by animal grazing and annual phenomenal bush burning. This has led to a reduction in soil carbon content and poor soil C:N ratio. With increase crop production, soils are amended with mineral fertilizer in most cases. In order to improve the soil carbon stocks and determine its losses in the soil, many studies have been conducted on the use of both inorganic and organic fertilizers as soil amendments and their impact on soil carbon partitioning. However, in the Guinea Savanna Agro-ecological zone of Ghana, there is paucity of information on the effects of mineral fertilizers on soil carbon emissions. Also, there are few reports of CO 2 flux from soils in the Guinea Savanna

Measurement and Modeling Nitrous Oxide Emissions from Ferric Luvisols in the Guinea Savanna Agro-ecological Zone of Ghana

Agricultural sector in Ghana contributes to about 60% of Gross Domestic Product (GDP) and is mainly characterized by fertilizer application to improve depleting soil fertility. With the increase in population and demand for increased productivity, application of inorganic fertilizers will result in enhanced greenhouse gas emissions. As nitrogen (N) is among the most limiting soil nutrient in the Guinea Savanna, chemical/organic fertilizers are applied in significant amounts to maintain crop productivity. Because of increased fertilizer and manure application to replenish dwindling soil fertility, the region is likely to become a significant source of nitrous oxide (N 2O) emissions. To study the effect of fertilizer application on N 2O emissions, Denitrification decomposition model (DNDC), a process-base model of carbon (C) and nitrogen (N) biogeochemistry in agricultural ecosystems was calibrated with field data obtained in 2013 and was used to predict the impact of N fertilizer source and rate of application on N 2O emissions. The linear equation between measured and modeled annual fluxes from ferric luvisols showed a

Improving Maize Yield on Ferric Lixisol by NPK Fertilizer Use

&lt;p&gt;The experiment was conducted to refined profitable NPK fertilizer rate for maize production on &lt;em&gt;Tanchera&lt;/em&gt; series (Ferric Lixisol, FAO, 2006) in the Sudan savanna agro-ecological zone of Ghana. RCBD design with four replications was used. Treatments evaluated were N = 0, 40, 80, 120, 160; P = 0, 45, 90 and K = 0, 45, 90 kg/ha. Results showed significant N rate effect on grain yield, benefit cost ratio and gross return (P ≤ 0.01). P and K did not show significant effect among these parameters. Application of nitrogen from 80-120 kg/ha may be recommended for improve grain yield and gross return of maize production on Ferric lixisol. Due to poor nature of soils, application of P and K up to 45 kg/ha may also be recommended for maize production.&lt;/p&gt;

Fertilizer and Genotype Effects on Maize Production on Two Soils in the Northern Region of Ghana

Soils in the Guinea Savanna agro-ecological zone of Ghana are depleted in major nutrients by continuous cropping and residue removal, resulting in low maize yields. While many studies have assessed the fertilizer requirements for maize, most did not account for the role of the soil type and maize genotype. A study was conducted on Plinthosol and Lixisol in the Tolon district of the Northern Region of Ghana to assess fertilizer and genotype effects on maize productivity. Two maize genotypes (i.e. Obatanpa -110 days to maturity) and (Dodzie - 75 days to maturity) were compared at three fertilizer application rates (i.e. 0-0-0, 60-15-35 and 90-25-50 kg ha&lt;sup&gt;-1&lt;/sup&gt; N, P K) in a randomized complete block design using four replications, with genotype allocated to the main plots and fertilizer levels to the subplots. Soils were characterized, revealing very low total N and available P concentrations in the top layers. Grain yield was significantly affected by maize genotype, irrespective of the soil type. The longer-duration (Obatanpa) tended to out yield the short duration genotype (Dodzie), and generally outperformed Dodzie in all yield parameters except for the harvest index on Plinthosol. Inorganic fertilizers significantly (P&amp;lt;0.001) increased yield and all yield parameters over the control on both soils, with yield increases of 84 and 90% at 60-15-35 and 90-25-50 kg ha&lt;sup&gt;-1&lt;/sup&gt; N, P K, respectively. Genotype by fertilizer interaction was highly significant (P&amp;lt;0.001) for grain yield on both soils. We conclude that farmers in the Guinea Savannah agro-ecological zone of Ghana need to supply nutrients to enhance grain yields of maize, irrespective of the prevailing soil type.

Verifying optimality of rainfed agriculture using a stochastic model for drought occurrence

It may be paradoxical but subsistence rainfed agriculture is the predominant source of food in Sub-Saharan Africa where the production uncertainty is associated with the stochastic nature of rainfall. This paper attempts to comprehend the rationale of this situation by a mathematical approach. Considering the level of drought severity as the zero-reverting Ornstein–Uhlenbeck process, optimality of rainfed agriculture is investigated in the context of stochastic control theory. Occurrence of drought terminating growth of crops is modelled with the concept of first exit time. A stochastic control problem allowing for virtual cost of irrigation, water stress to crops, and benefits of farming is formulated with irrigation effort as the control variable. The Hamilton–Jacobi–Bellman equation governing the optimal control is studied to identify the set of cost functions optimizing rainfed agriculture in an inverse problem approach. Data and information were collected in the coastal savanna agro-ecological zone of Ghana, to identify model parameters, formulate the stochastic control problem, solve the inverse problem, and then verify optimality of rainfed agriculture. The results indicated that rainfed agriculture is not optimal when the crop is more tolerant to water stress.

English

The agronomic performance and economic benefit of rice seed from two sources (farmer-saved and certified seed) at different nutrient management regimes in the Guinea Savanna agro-ecological zone of Ghana were evaluated. A total of 14 on-farm multi-locational trials were established in 2011 and 2012 cropping seasons using Participatory Learning and Action Research (PLAR-IRM) approach to technology dissemination. Regression analysis shows statistically significant differences (P <0.01) of treatment effect in terms of grain yield (kg/ha) for both certified and farmer-saved seed. The highest grain yield of 6,833 kg/ha was recorded for certified seed at full fertilizer recommendation rate for the 2012 growing season while the lowest grain yield of 30 kg/ha was recorded for famer saved seed at zero fertilizer management level for the same cropping season. Returns from cultivating certified rice seed was found to be economically superior to farmer saved seed at all levels of fertilizer management. Key words: Certified improved rice, farmer learning centres, Guinea Savanna agro-ecological zone, integrated soil fertility management.

Groundnut (Arachis hypogaea L.) varietal response to spacing in the Guinea Savanna agro-ecological zone of Ghana: Nodulation and nitrogen fixation.

Agriculture and Biology Journal of North America ISSN print:2151-7517, ISSN Online:2151-7525, doi:10.5251/abjna.2013.324.335 C2013, ScienceHup, http://www.scihub.org/ABJNA

Improved Crotalaria cover crop fallow system for sustainable maize production in the northern Guinea Savanna agroecological zone of Ghana

An on-station trial was carried out at the Research Farm of the Faculty of Agriculture, University for Development Studies, Tamale, in the northern Guinea Savanna agroecological zone of Ghana. The study compared different seeding rates of leguminous cover crops, inorganic fertilization, and a combination of the two in a small-scale cereal-based production system. The experiment was conducted for 2 years within a 3-year fallow system to investigate the use of Crotalaria ochroleuca and Crotalaria retusa as 1 and 2 years' fallow systems. Crotalaria ochroleuca seed fallow at 50 kg ha-1 was more efficient in above-ground biomass production and nutrient accumulation than Crotalaria retusa seed fallow at 50 and 100 kg ha-1 of cover crop regrowth. The above-ground biomass production and nutrient accumulation by the Crotalaria species at 100 kg ha-1 of seeds was higher than at 50 kg ha-1 of seeds. The results showed that C. ochroleuca and C. retusa can accumulate higher soil nutrients at higher seed rates. The average grain yield increase for all the treatments between 2001 and 2002 were 4.6 and 3.0 per cent for "Dobidi" and "Okomasa" at 100 kg ha-1 of Crotalaria seeds, respectively. Grain yields from the Crotalaria fallow species plus fertilizer performed better, followed by fertilizer treatment and Crotalaria fallow systems. Two years' Crotalaria fallow systems at 100 kg ha-1 were more profitable than at 50 kg ha-1.

Field evaluation of neem seed extract for the control of major pests of cowpea in northern Ghana

Field studies were conducted at the Experimental Farm of the Savanna Agricultural Research Institute (SARI), Nyankpala, northern Ghana, during the 2006 cropping season to evaluate the effect of aqueous neem (Azadirachta indica A. Juss) seed extract at 5, 10, 15 and 20 per cent on Aphis craccivora Koch., Megalurothrips sjostedti Tryb., Maruca vitrata Fab., and a complex of pod and seed-sucking bugs of cowpea (Vigna unguiculata L. Walpers), as well as their effect on the grain and fodder yields of the crop. The results showed that the incidence and abundance of all the target insect pests were significantly affected by the neem extract treatments. Cowpea grain yield was significantly higher in all the neem-treated plots than in the control. The 15 per cent neem seed extract treatment proved as effective as that of the 20 per cent in increasing the grain yield of the cowpea crop. However, none of the neem treatments was as effective as the synthetic insecticide (Karate) in cowpea grain yield. However, grain quality for the 15 and 20 per cent treatments was similar to that for the Karate treatment. Cowpea fodder yield was found to decrease with increasing concentration of the neem extract. Benefit-cost analysis for the grain and fodder yields showed that the 15 and 5 per cent neem extract treatments, respectively, had the best benefit-cost ratios. Therefore, the 15 per cent neem seed extract is recommended for use in controlling the major field insect pests of cowpea for maximum grain yield in the Guinea savanna agroecological zone of Ghana. However, for situations in which the grower is strapped for cash or neem seeds are inadequate, the 5 or 10 per cent extract may be used. The 5 per cent neem seed extract is recommended for dual-purpose cowpea cultivars for maximum returns on grain and fodder yield.

The use of human waste for peri-urban agriculture in Northern Ghana

AbstractIn Ghana, studies on the use of organic materials to increase soil productivity have focused on crop-residue management, use of green and animal manures, and legume cover cropping. Few studies have assessed the use of human waste for agriculture, even though this is widely practiced by farmers in the northern part of the country. This study was carried out to investigate the stakeholders in the use of faecal sludge (FS) for crop production in Tamale and Bolgatanga municipalities in the guinea savanna agroecological zone of Ghana. The aim was to determine the driving factors, constraints and potentials for this practice. Field survey and focus group discussions were carried out among 90 farmers who use FS, and officials of the Municipal Sanitation Unit were interviewed. Sixty-four percent of farmers interviewed used FS as a cost-effective way to improve soil fertility and increase yields of maize and sorghum. Sludge is discharged by spreading it on the soil surface, or it is stored and dried in pits during the dry season and incorporated into the soil at the onset of the rainy season. The high temperatures of the savanna climate and this long period of drying allow sludge to be handled easily. Although this treatment is perceived to reduce the number of pathogens in dried sludge, 22% of farmers complained of itching feet and foot rot after working with FS, which is done without wearing protective foot covering. This constraint is coupled with the foul smell, transport problem and public mockery associated with the use of human waste for agriculture. In spite of these problems, there is competition for FS among farmers, due to benefits derived from its use. Further investigation is required to ascertain the causes of itching feet and foot rot, and there is a need for education on proper handling and appropriate hygiene practices when working with FS. Information regarding optimal FS application rates is also required.

Intercrop performance of maize, sorghum and soybean in response to planting pattern

Mixed cropping of cereals and legumes dominate the cropping systems of most farmers in the northern Guinea Savanna agroecological zone of Ghana. The objective of the study was to determine the appropriate crop mixture ratios for higher productivity of maize/soybean and sorghum/soybean cropping systems. The experiment was conducted during the 1997 and 1998 cropping seasons at the Research Farm of the Faculty of Agriculture, University for Development Studies, Tamale, Ghana. Results showed that seed yields of the monocropping maize, sorghum and soybean were higher than the intercropping yields of maize/soybean and sorghum/soybean. The sorghum/soybean intercropping gave a mean Land Equivalent Ratio (LER) of 0.88 and 0.93 in 1997 and 1998 respectively while the maize/soybean intercropping gave mean LER of 0.82 and 0.81 in 1997 and 1998, respectively. There was lesser interspecific competition between the sorghum/soybean while greater interspecific competition between maize/soybean intercropping was observed. The sorghum/soybean intercropping gave a mean Relative Crowding Coefficient (RCC) of 1.57 and 1.23 in 1997 and 1998 respectively which was more productive than the maize/soybean intercropping with mean RCC of 1.01 and 0.88 in 1997 and 1998, respectively. Based on the LERs and RCCs analyses, three rows of sorghum or maize alternating with three rows of soybean seem more productive. JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 2 (2000) pp. 31-35