Open Access Original Research Article

Effect of Intercropping on Nitrogen Fixation of Three Groundnut (Arachis hypogaea L) Genotypes in the Guinea Savanna Zone of Ghana

S. Konlan, J. Sarkodie-Addo, M. J. Kombiok, E. Asare, I. Bawah

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2015/11150

An experiment was conducted on the research farm of the Savanna Agricultural Research Institute (SARI), Nyankpala, in the Guinea savanna agro-ecology to study the nitrogen fixation performance of three groundnut genotypes (Jenkaar, Kpanieli and Nkosuor) intercropped with maize (Obatanpa variety). The experiment was laid out in randomized complete block design with four replications. Treatments evaluated were sole groundnut, sole maize, single-row groundnut intercropped with single-row maize (G1M1), double row groundnut intercropped with single-row maize (G2M1), single-row groundnut intercropped with double-row maize (G1M2) and double-row groundnut intercropped with double-row maize (G2M2). Data collected included canopy width, number of branches plant-1, above ground dry matter, residue and seed N, stover yield and stover N             (kg N ha-1). The results showed that with the exception of Kpanieli, intercropping significantly (P<0.05) reduced the growth parameters and nitrogen fixation of the groundnut genotypes. Row patterns that allowed more space and light penetration significantly (P<0.05) improved nitrogen fixation. Even though all three groundnut genotypes performed within the reported levels with regard to nitrogen fixation, the Kpanieli genotype intercropped with maize using the double row groundnut-single row maize (G2M1) pattern was more beneficial.

Open Access Original Research Article

Fertilizing Effect of Swelling Clay Materials on the Growth and Yield of Bean “Phaseolus vulgaris” on the Sandy Ferruginous Soils from Mafa Tcheboa (North Cameroon, Central Africa)

Basga Simon Djakba, Nguetnkam Jean Pierre

International Journal of Plant & Soil Science, Page 10-24
DOI: 10.9734/IJPSS/2015/13180

Amendment of sandy ferruginous soils by swelling clay materials can be a promising solution to improve their fertility and thus enhance crop yield. In this study which aims at valorization swelling clay materials in the mineral fertility of ferruginous soils, a pot experiment was conducted using ferruginous soils from northern Cameroon which were sampled at Mafa Tcheboa, and amended by swelling clays materials collected also in the North Cameroon. The effect of swelling clay application on the growth and productivity of common bean “Phaseolus vulgaris” was followed by means of measures of growth and yield parameters. An experimental design which consisted in a randomized complete block design (RCBD) is constituted of two series of five treatments each one: the control (ST), the control mixed with 300 g of clay before sowing (SAS), the control with 20 g of clay in the hole of sowing (STS), the control with 20 g of clay at the germination stage (SAL) and the control with 20 g of clay at the approaching flowering stage (SAF). Each treatment was replicated ten times in every serie. The control treatment is only soils of Mafa Tcheboa without any clay application; they are sandy, acid and display a low CEC with kaolinite as main clay mineral, while swelling clay materials are basic and display a cation exchange capacity (CEC) 3 times higher than that of controls, and made up mainly of smectites. On the geochemical point of view, both materials are constituted mainly by SiO2, Al2O3, Fe2O3 as major elements; and Ba, Zr and Sr as traces elements. All the treatments were irrigated with 250 ml of water one time all two days during the growing stage. The growth and yield components were measured every three days. 14204 measures of growth components and 35440 measures of yield components were made. The results indicate an important increase of stem length and its branches, leaves number, leaflet length, leaflet width, main root length and number of its ramifications in the soils amended by swelling clay materials. About 2.5 times of yield were obtained from those treatments compared to control in one hectare. The germination stage and the flowering stage are the best periods to apply swelling clay materials. The overall results indicate that swelling clay material can be used to enhance bean’s crop yield in ferruginous soils from Mafa Tcheboa and therefore are interesting alternative petrofertilizers to very expensive chemical fertilizers.

Open Access Original Research Article

Morphological Variation and Ecological Structure of Chrysophyllum albidum G. Don

S. Dadegnon, C. Gbemavo, C. Ouinsavi, N. Sokpon

International Journal of Plant & Soil Science, Page 25-39
DOI: 10.9734/IJPSS/2015/11385

Chrysophyllum albidum is a tropical forest species which plays tremendous socioeconomic role in west Africa because of its fruits large comsuption and trade.

Morphological variation and ecological structure of Chrysophyllum albidum G. Don were assessed in Benin in order to contribute to the species domestication. Dendrometric parameters such as diameter at breast height, total height, and bole heigt were measures from 120 individual trees across two ecological zones and four different provenances. In addition, morphometric parameter related to fruits and seeds such as fruit length, fruit width, fruit weigh, seed length, seed width and seed weigh were measured for 1,800 fruits and 1,800 seeds. Principal component analysis was performed on the untransformed morphometric data using the correlation matrix.

Diameter and height classes distribution of C. albidum in each ecological zone adjusted to Weibull distribution showed a bell shaped curve with left dissymmetry, characteristic of young stands (form coefficient between 1 and 3.6). From principal component analysis, no differentiation was observed, indicating that accessions from different agroecological zones were similar morphologically. However analysis of variance performed separately on morphometric data revealed some significant difference among agroecological zones and among provenances as far as bole height (P = .000) and fruits and seeds size (P = .021) are concerned.

Although morphological variability in C. albidum between provenances and between agro-ecological zones is low there is pathways for selection purposes since bole height as well as fruits and seed weight exhibited large morphological variability among agro-ecological zones.

Open Access Original Research Article

Evaluation of Different Improved Upland Rice Varieties for Low Soil Nitrogen Adaptability

P. A. Sikuku, J. M. Kimani, J. W. Kamau, S. Njinju

International Journal of Plant & Soil Science, Page 40-49
DOI: 10.9734/IJPSS/2015/13637

Scarcity of nitrogen fertilizer is a major constraint to rice production particularly in developing countries. Low soil fertility prevalent in farmer’s fields has led to low rice yields and the ever escalating fertilizer prices have made this important input unaffordable to most smallholder farmers who have limited resources for purchasing the required inputs. The Mwea Upland rice (MWUR) varieties were bred under low fertilizer input environment while other authors have indicated that the New Rice for Africa (NERICA) gives high yields under low input conditions. There is therefore need to identify the superior rice varieties that are adaptable to low nitrogen levels. Thus, the objective of this study was to investigate the effects of different rates of nitrogen fertilizer on improved upland rice varieties and identify the low input adaptable varieties. Field studies were conducted at Alupe in Western Kenya under rainfed upland conditions between August 2012 and April 2013. The experiment layout was split plot factorial in a Randomized Complete Block Design with three replicates. The main plot treatments were four rates of nitrogen fertilizer levels which were; 0 (control), 40, 80 and 120 kg ha-1 applied as calcium ammonium nitrate (26% N) in two equal splits; 21 days after sowing (DAS) and at panicle initiation (46 DAS). Sub-plots consisted of four MWUR varieties namely MWUR 1, MWUR 2, MWUR 3, MWUR 4; and four NERICA varieties namely NERICA 1, NERICA 4, NERICA 10 and NERICA 11. The parameters measured included plant height, tiller number, filled grain ratio percentage and yield components. In the study, nitrogen treatment showed significant effect on plant growth and the measured parameters increased significantly with increase in nitrogen level. MWUR varieties studied were more adaptable to low nitrogen conditions as compared to NERICA varieties. The NERICA varieties recorded higher yield at high nitrogen levels as compared to MWUR varieties. However, NERICA 4 gave higher yield as compared to other NERICA varieties regardless of the nitrogen level. Results from our study suggest that MWUR 1 and 2 and NERICA 4 were more tolerant to low nitrogen as compared to MWUR 3 and 4 and NERICA 1, 10 and 11, because of higher height, more tiller number, higher filled grain ratio percentage and higher yield component as compared to the other studied varieties and may be suitable for soils low in nitrogen.

Open Access Original Research Article

Soil Fertility and Biodiversity of Arbuscular Mycorrhizal Fungi Associated with Cashew’s (Anacardium occidentale L.) Cultivars Characteristics in Benin (West Africa)

I. Balogoun, A. Saïdou, N. S. Kindohoundé, E. L. Ahoton, G. L. Amadji, B. C. Ahohuendo, S. Babatoundé, D. Chougourou, A. Ahanchédé

International Journal of Plant & Soil Science, Page 50-63
DOI: 10.9734/IJPSS/2015/13817

The present study aims to assess the biodiversity of arbuscular mycorrhizal fungi (AMF) associated with cashew (Anacardium occidentale L.) cultivars characteristics in Benin (West Africa). 108 soil samples were collected at 0-20, 20-40 and 40-60 cm depth under cashew trees at Glazoué in the centre Benin. Cashew’s cultivars characteristics regarding nut and apple size, apple colors and classes of Diameter at Breast Height (DBH) were the treatments. Soil chemical properties, AMF spores’ density and the diversity of AMF in the soil were assessed. Plantation of cashew improved the stock of soil organic carbon (11.24±0.63 and 10.93±0.71 g/kg for 0-20 cm soil depth respectively for cultivars producing big nuts and big apples and cultivars producing small nuts and small apples) and total nitrogen content (1.29±0.11 and 1.21±0.12 g/kg for 0-20 cm soil depth respectively for cultivars producing big nuts and big apples and cultivars producing small nuts and small apples) but it depletes available phosphorus (36.86±6.53 and 41.42±9.22 mg/kg for 0-20 cm soil depth respectively for cultivars producing big nuts and big apples and cultivars producing small nuts and small apples) and exchangeable potassium (0.93±0.10 and 0.79±0.04 cmol/kg for 0-20 cm soil depth respectively for cultivars producing big nuts and big apples and cultivars producing small nuts and small apples). Seven species of AMF (Scutelospora gregarine, Acaulospora colossica, Acaulospora lacunosa, Enthrophospora infrequens, Glomus hoi, Glomus geosporum and Glomus sp.) were identified. They belong to three families and four genera. The species belonging to Glomeracea family were dominants (91.8%) against 5.5% and 2.7% respectively for the Gigasporaceae and Acaulosporaceae. In general, the average numbers of AMF spores were 5.63±0.26; 3.54±0.19 and 1.94±0.15 per gramme of dry soil respectively for 0-20, 20-40 and 40-60 cm depth. The community of AMF was fairly diversified in the soil under cashew’s trees. There was an equitable distribution of AMF genera associated with cashew’s cultivars characteristics tree.

Open Access Original Research Article

Magnesium Adsorption in Selected Cocoa Growing Soils Within Southwestern Nigeria

Paul E. Aikpokpodion, K. N. Awokoya, T. Osobamiro, S. M. Omotoso

International Journal of Plant & Soil Science, Page 64-73
DOI: 10.9734/IJPSS/2015/13870

Magnesium is one of the vital nutrients required by Theobroma cacao L. for optimum growth and yield. Several authors have reported the deficiency of magnesium in Nigerian cocoa plantations and ended up recommending the application of magnesium fertilizer based on agronomic soil test. Application of fertilizer without considering the potential of each soil to retain certain proportion of the applied fertilizer will lead to reduced available Mg in the soil solution. The study was carried out to evaluate the sorption capacity of selected cocoa growing soils in southwestern Nigeria. Soil samples were equilibrated with 20, 40, 60, 80 and 100 mg Mg L-1. Result showed that, Freundlich equation best described the adsorption of magnesium onto the soil surfaces. Adsorption of magnesium was highest in Owena soil. Hence, more magnesium fertilizer will be required by Owena soil compared with Ekiti, Ibadan, Ile-Ife and Bodo soils to produce equal amount of available magnesium ions in soil the solution.