International Journal of Plant & Soil Science

Soybean is a food security crop in Benin due to its high nutritional value but its yield in the farmers’ cropping system is very low. The present study aims to provide appropriate response to the yield variability among fields in two agro-ecological zones of Benin namely: Southern Borgou zone (AEZ 3 in the north) and cotton zone of central Benin (AEZ 5). Soil samples were collected from 0-20 cm depth in 120 fields (50 in the AEZ 3 and 70 in the AEZ 5). pH (water), soil organic carbon (Walkley and Black method), total nitrogen (Kjeldahl method), CEC (0.01 N ammonium acetate at pH 7 method) and available phosphorus (Bray 1) were determined in the laboratory of Soil Science Water and Environment (LSSEE) of the National Agricultural Research Institute of Benin (INRAB). Cropping system (crop rotations, soil fertility management practices) were also collected using an open ended questionnaire. Classification and regression trees (CARTs) models were used for data analyses. Soybean yield variability among the agro-ecological zones were registered and the highest yield recorded was less than 1 t.ha^-1. Considering soil characteristics, soil organic matter level was the most important variable determining yield variability. Furthermore, quantities of P applied and farmyard manure were cropping practices inducing yield variability (86.4% and 15% of the variability respectively). Our results also show that, yield differences noticed among the agro-ecological zones were induced by CEC and pH (water). The study suggested promotion of integrated soil fertility management practices to sustain soybean yield in the study area.

Pedogeomorphological categorization of selected soil profiles developed on alluvial deposits in Mbogo - Komtonga traditional irrigation scheme, Mvomero District in Morogoro Region, was carried out during February 2017. Using standard grids, pedogeomorphic approach and standard manuals, detailed soil survey was conducted which enabled delineation of soil mapping units from which the representative profiles were identified, described and sampled. Eighteen samples were collected at a depth of 0–30 cm and from each horizon of the selected soil Master pits and analyzed for physico – chemical characterization. Based on FAO soil survey system of classification, the representative profiles were classified as Eutric Fluvisols and/or Eutric Cambisols. The pedon was deep to moderately deep, well to moderately well drained, with brownish black clay top soils or dull yellowish brown soil colors with sub soils stratified with fS, C, CL and SCL. Top soil pH was strongly to medium acid to medium or slightly acid sub soils. OC showed no decline in soil quality. N was very low to low, P and K levels were medium to low or very low; CEC was high to very high in all the profiles. Ca²⁺ and Mg²⁺ in the top soils were high to very high and very low or low to medium in the sub soils. Na⁺ was rated as low to medium in the top soils of all profiles and low to very low in the sub soils. Base saturation was > 50% and was rated as high. Topsoil Bd and total porosity were ideal to medium. AWC was medium and water storage capacity (AWSC) was good and sufficient for paddy production and other upland crops. These results suggest that where the soil parameters were low to very low as for N, P and SOM should be included in the overall soil fertility management program. Soil reaction may be regulated during irrigation development by provision of sufficient drainage, discharge and flood control structures and minimum application of lime if required.

Four soil profiles (Yala, Galana, Baringo and Bondo) that represent different ecology, physiography and pedological variability were described to study their morphology, soil physico-chemical characteristics and to classify them using two internationally known soil classification systems. Soil samples were taken from designated pedogenic horizons for physical and chemical analysis in the laboratory. These soils are deep to very deep (> 110 cm) and well-drained except in Galana which was imperfectly drained, with varying textures. In Bondo, the soils are moderately acid (pH 5.6 – 6). In Baringo, the soil profile is acidic (< 5.0) while in Galana moderately alkaline (pH 7.3 - 8.3) and Yala soils are moderate to strongly acid (5.1 - 5.7). The organic carbon (< 0.6%) and organic matter levels (1 – 2%) were low and decreased down the profiles in all. The soils have low to moderate fertility. The base saturation of the studied soils is rated as very high (> 80%) in Galana and Baringo and low (< 50%) in Yala and Bondo pedons. The soils are non-saline as indicated by the low values of electrical conductivity (< 1.7dS/m) in the pedons. The soils are non-sodic (ESP < 6%) in Bondo and Yala, however moderately sodic (ESP 11-15%) in Galana and Baringo. Ochric horizon was the main diagnostic epipedon while ferralic, argillic and cambic horizons were the diagnostic B horizons. According to USDA Soil Taxonomy, the soils were classified as Typic Haplustox (Yala), Typic Haplocalcids (Galana), Typic Eutrudepts (Baringo) and Plinthic Haplustults (Bondo) corresponding to Haplic Ferralsols, Luvic Calcisols, Haplic Cambisol and Cutanic Plinthic Acrisols in the WRB for Soil Resources. The general fertility of the soils of the areas is discussed highlighting their potentials and constraints.

Aim: This study was carried out to isolate, identify and characterize fungal pathogens associated with post-harvest spoilage of cucumber.

Study Design: This research study was done using random sampling technique. 

Place and Duration of Study: The experiment was carried out from March to June, 2019 at biology laboratory Federal College of Forestry, Jos.

Methodology: Fungi isolates were obtained from diseased portions of the cucumber fruit samples cultured on PDA media and incubated at 28ºC2 for seven days. The mycelial were identified macroscopically and microscopically. Pathogenicity tests were conducted for all the fungal pathogens identified by inoculating healthy cucumber samples and incubating for ten days with the readings being taken at two day intervals. The data obtained were analyzed using ANOVA and means were separated using LSD at P ≤ 0.05.

Results: Aspergillus fumigatus, Fusarium sp., Geotrichum candidum and Yeast sp were isolated and identified. Result showed that Gada biu market was the most heavily infested location with all the fungal isolates. Geotrichum candidum constituted the highest (50%) occurrence of fungal isolates from all locations. All the fungal isolates were found to be pathogenic on cucumber fruits, with Fusarium being the most destructive, followed by yeast and Geotrichum candidum and the least was Aspergilus fumigatus.

Conclusion: The results obtained in this study showed the isolates identified were involved in Cucumber spoilage. Therefore, Careful handling of Cucumber fruits should be ensured to prevent the spread of these pathogenic fungi.

The aim of this study was to evaluate the effect of two organic wastes used as soil amendments i.e. filter mud cake (FMC) and vinasse (V) on some physical and chemical properties of sandy and loamy sandy soils. Applications of organic were incubated with the soils for a three periods of 15, 30 and 60 days at four application rates (0, 0.5, 1 and 2%). This study was carried out in a two way randomized completely block design with three replications. After incubation periods, bulk density, porosity, water retention, soil pH, electrical conductivity (EC) and organic matter were determined.

Results showed that the values of soil bulk density and soil pH were decreased with increasing the application rates of filter cake or vinasse compared with the control in two soils. In addition, application of different filter mud cake and vinasse rates to the study soils increased soil porosity, field capacity (FC), wilting point (WP), available water (AW), electrical conductivity (EC) and organic matter contents (OM) as compared to control at different period incubation time. The data of this study concluded that, organic wastes or byproducts of sugar industries could be applied to improve some soil properties.