Open Access Original Research Article

Effect of Enriched Sheep Manure Rates on Physico-Chemical Parameters of Tea Soil in Timbilil Tea Estate, Kericho, Kenya

Boiwa Mercy Chepkorir, Sitienei Ann, Kere George Mbira

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2018/44866

The regular harvesting of tea (two leaves and a bud) implies that nutrients are continuously mined from the soil. On the other hand, integrated soil fertility management (ISFM) which involves the combined use of organic and inorganic fertiliser is good for improved soil health. Therefore, the study was carried out to determine the effect of enriched sheep manure rates on physico-chemical parameters of tea soil. An ongoing field trial in Timbilil Tea Estate in Kericho started in 1985 to study the response of sheep manure, NPK 25:5:5 and a combination of both on tea plants were used. The trial was set up in a Randomized Complete Block Design (RCBD) with three replicates. Forty-two composite soil samples were collected randomly from each of the experimental plots. The data collection process included soil sampling during the short rain season in 2017 and annual tea yield sampling. The samples were analysed for the total organic matter, nitrogen content, bulk density, porosity, soil pΗ, porosity, particle density and soil moisture content. Results showed that fertiliser types significantly (p<0.05) affected SOM with enriched sheep manure giving the highest values. Fertiliser rates had no significant (p>0.05) difference on SOM. Fertiliser application at the highest rate of 240 kg N/ha had the lowest SOM content, which means high fertiliser application, causes more harm than good. Therefore, enriched manures increase SOM content in the soil which could improve productivity in the tea industry.

Open Access Original Research Article

Influence of P Fertiliser on Nodulation, Growth and Nutrient Content of Cowpea (Vigna unguiculata L.) in Acidic Soils of South Western Kenya

G. N. Chemining’wa, J. K. Ngeno, M. J. Hutchinson, S. I. Shibairo

International Journal of Plant & Soil Science, Page 1-12
DOI: 10.9734/IJPSS/2018/44765

Field experiments were carried out in Kericho East (0°22' S, 35°17' E) and Bomet central (0°47' S, 35°21' E) to determine the effects of liming and phosphorous (P) fertiliser on nodulation, growth, yield and nutrient content of cowpea in the strongly and moderately acidic soils. The treatments comprised of three cowpea varieties (KVU 27-1, M66 and Ngor) supplied with lime  (0 t CaO ha-1 and 4 t CaO ha-1) and P fertiliser  (0 kg P ha-1, 25 kg P ha-1 and 50 kg P ha-1), laid out in a randomized complete block design in a 2 x 3 x 3 factorial arrangement. Data collected were: nodule number and weight, leaf area index, shoot dry weight, shoot and grain N and P uptake, grain yield, tissue N and protein content. Results showed that liming had no significant (≤.05) effects on cowpea nodulation at experimental sites characterised by strongly acidic (pH 4.85) and moderately acidic (pH 5.58) soils, but increased shoot dry matter by 35% and grain N and P uptake in the strongly acidic soils of Kericho East by 1.8 kg ha-1  and 2 kg ha-1 respectively. In absence of liming or P fertiliser, grain yield was not recorded in two varieties at Kericho East. Application of 50 kg P ha-1significantly enhanced nodulation at both experimental sites; it increased nodule dry weight at Bomet Central by 27% in the short rains than in the long rains season. Lower P rate (25 kg ha-1) increased shoot dry matter by 46% at Bomet central, but 50 kg P ha-1 increased growth parameters of cowpea by over 100% at Kericho East in all seasons. It is concluded that liming is not beneficial to cowpea nodulation in soils with similar ecological conditions reported in this study. Application of 50 kg P ha-1 is required for cowpea production in strongly acidic soils.

Open Access Original Research Article

Chemistry and Mineralogy of Soils Derived from Different Parent Materials in Southeastern Nigeria

E. O. Azu, Donatus, V. E. Osodeke, I. M. Ukpong, A. F. Osisi

International Journal of Plant & Soil Science, Page 1-16
DOI: 10.9734/IJPSS/2018/44764

Knowledge of the soil minerals is an important index in understanding the soil fertility properties since mineral surfaces serve as both the source and sink of plant nutrients. Soils developed from contrasting parent materials viz: Coastal Plain Sand, Sandstone, Basalt and Shale at different soil horizons (0-20 cm, 20-40 cm and 40-60 cm) in South Eastern Nigeria were studied for mineralogical properties.  Soil samples were collected from the different parent material in three replicates and a total of thirty six composite samples were collected. These samples were subjected to X-ray diffraction analysis with Siemens D5000 diffractometer using Cuką radiation with Iron(fe) filter (λ = 1.5409A) at 40kv and 30 mA, at a scan rate of 2° per minute. The experimental design was a 4 x 3 factorial in Randomized Complete Block Design (RCBD). Statistical analysis revealed significant (P<0.05) variation in soil physical and chemical properties with parent material and soil depth except organic matter “OM”, total nitrogen “TN”, magnesium “Mg+2” total exchangeable acidity “TEA” and base saturation “BS” where variations were not significant. However, interaction between parent material and soil depth was only significant in influencing the pH. Top soil layers had a significant greater amount of OM, TN, AP, cations, Sand and Silt. Generally, soil of shale formation was superior, followed by basaltic soil in these soil fertility indicators, while soil of Coastal Plain Sand formation had the least amounts. Parent material and depth played dominant roles in the type and distribution of clay minerals in the study area. The concentration of these minerals varied with parent material and soil depth. Significant variations with parent material were observed in the minerals identified except in Halloysite and Chlorite where non-significant variations were observed. While variations with depth were statistically significant (P<0.05) in Chlorite, Geothite, Hermatite, Montmorillonite and Quartz, the influence of the interaction between parent material and soil depth were only significant in Gibbsite, Kaolinite and Montmorillonite. Soil derived from Coastal Plain Sand had, Kaolinite (9.94 to 28.83%) and Quartz (56.4 to 87.3%) as the dominant clay minerals and these decreased with depth. Soil formed in shale had mixed clay mineralogy of montmorillonite (14.37 to 21.88%), goethite (23.58 to 25.09 %), hermatite (20.39 to 24.19%), gibbsite (8.48 to 12.10%), kaolinite (6.89 to 3.56%) and others with depth. Soil formed in sandstone has Kaolinite accounted for 26.42 to 31.26%, goethite, 7.77 to14.87%, and quartz accounted for 35.4 to 51.8%. Other minerals identified were: hermatite (4.58 to 14.62%), gibbsite (1.70 to 5.23%), while soils derived from basalt had kaolinite (14.64 to 27.44 %), quartz (23.7 to 42.5%), hematite (11.0 to 23.14%), goethite (13.94 to 26.48%) as the dominant crystalline minerals present in the soil. The study concludes that the mineralogy of Southeastern Nigeria consists of quartz, kaolinite, hermatite, goethite and gibbsite with traces of smectite in soil derived from shale as the dominant minerals and their percent mass occurrences varied with soil parent material and depth. Since the mineralogy of the soils studied is mainly kaolinitic, the soils can said to be low in terms of fertility and therefore require adequate soil fertility management strategies to enhance their fertility and productivity.

Open Access Original Research Article

Temperature and pH Factor on Cocoa Bean-Based Ochratoxin-A (OTA) and Detoxification Potential of Rhizopus stolonifer

A. O. Adeji, A. B. Fadara, D. O. Adeniyi

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2018/39790

Aim: To study the effect of temperature and pH on detoxification potential of Rhizopus stolonifer on Ochratoxin-A (OTA) from cocoa beans in Nigeria.

Place and Duration of the Study: This study was carried out in the Plant Pathology laboratory of Cocoa Research Institute of Nigeria (CRIN) for the period 2013-2017.

Methodology:  Stored cocoa samples were collected from Cross-River, Ondo and Osun States in Nigeria, assayed on Potato Dextrose Agar. The pure culture of the isolate of Rhizopus stolonifer used as a detoxifying agent was obtained from CRIN Mycobank. Aspergillus ochraceus, A. niger and Penicilium verrucossum cultured from cocoa bean samples were used in the study. These ochratoxigenic fungi were cultured on Yeast Extract Sucrose (YES) agar in the dark for 14 days for detection and detoxification of toxin. Ochratoxin-A (OTA) productions were detected using retention factor (RF) on simple Thin Layer Chromatography (TLC) plate of solvent system Toluene: Ethyl acetate: Formic acid (5:4;1 v/v/v) while confirmation of OTA was done using 365nm wavelength of ultraviolet (uv) light.

Results: Five fungi genera: Aspergillus, Penicilliun, Fusarium, Yeast and Rhizopus were cultured from cocoa beans sample across the study locations: The tested temperature and pH indicated that Aspergillus ochraceus and Penicillium verrucosum had retention factor (Rf) value of 0.88 to 1.29 which showed green-blue colouration under Ultra Violet (UV) light confirming the presence of Ochratoxin-A (OTA) while A.nigerisolate had RF of 0.88-0.55 with yellow to olive yellow colour confirming the absence of OTA.  Rhizopus stolonifer isolate detoxify OTA when cultured with A. ochraceus and P. verucossum at pH 7.0 and 9.0 and 25°C-30°C with yellow to brownish-yellow colouration confirmed as a less toxic metabolites (Citreoviridin, Palutin and Palitantin) while no toxin was detected in A. niger plus R. stolonifer after detoxification.

Conclusion: There is variability in retention factor as temperature and pH changes. Production of OTA occurred between 25-30°C and pH of 4.0 to 9.0 but peaked at pH 4.0 with Rf 1.3 at neutral pH and 25°C enhanced detoxification potential of R. stolonifer. Thus R. stolonifer can be developed to detoxify OTA from Cocoa beans at favourable eco-physiological factor.

Open Access Review Article

Anatomical Features of Sugarcane (Saccharum officinarum L.) Treated with Thiamine

Lucas Aparecido Manzani Lisboa, Paulo Alexandre Monteiro de Figueiredo, Samuel Bispo Ramos, Victor Garcia Venâncio, Vinicius Anjos Aragão, Wagner José Machado da Silva, Gabriel Geminiano da Silva, Letícia Sodario Bezerra de Araújo, Igor José Pereira de Salis, Augusto Costa Mota

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2018/44843

This worked aimed to know the anatomical features of sugarcane (Saccharum officinarum L.) treated with thiamine. A completely randomized experiment was used and designed in a double factorial scheme at 3x5 levels, in which the first factor consists of a variety of sugarcane: RB86-7515; RB96-6928 and CTC-4; the second factor was thiamine doses in five levels: zero mgL-1; 100 mgL-1; 200 mgL-1; 400 mgL-1 and 800 mgL-1; fifteen treatments were made with five replications, 75 plots in total. Tissues from the leaves and roots were influenced by the exogenous action of thiamine as used at planting, displaying a positive response, doses above 400 mg L-1 can be a limiting factor to the development of these tissues. Factor regarding the sugarcane variety did not influence the anatomy of leaves and roots. Concentrations till 400 mg L-1 of thiamine, at the exogenous administration, promoted a better development on morph-anatomic features of leaves and roots in the planting of sugarcane seedlings.