Evaluation of fallow and cover crops for nematode suppression in three agroecologies of south western Nigeria

A study was conducted in three agroecological zones of south-western Nigeria to evaluate the effect of siam weed (Chromolaena odorata) and mucuna (Mucuna utilis) cover/fallow crops on plant-parasitic nematode population. The natural bush regrowth was used as control. Plant-parasitic nematodes were identified and counted during the fallow periods. Eleven genera of nematodes were identified and three (Meloidogyne, Pratylenchus, and Helicotylenchus) species were predominant across the trial locations.Other important genera present were Scutellonema, Tylenchorhynchus and Rotylenchus species. Nematode population densities of pre-crop were lowest in Alagba soil (Rhodic lixisols) at Ikenne in the wet forest zone of Nigeria. The populations in Iwo soil (Rhodic haplustalf) at Ibadan, a dry forest zonewas lower than in the Temidire soil (Plinthic luvisol) at Ilora in the derived savannah of south-western Nigeria. There was significant suppression of nematode population densities under the different crops as the fallow period increased. The population reduction in the different locations depended on the nematode species and the cover crops. The natural bush re-growth had the least effect on the nematode suppression at the end of the fallow period. On the average, siam weed fallow reduced nematode population densities by 67-79%, mucuna by 64-72% and the natural bush by 30-49% across the trial locations. For effective nematode suppression with fallow cropping, proper determination of the principal nematode species predominant in an environment is essential

Quality Assessment and Suitability Evaluation of Soils under Tuber-based Cropping System in Katsina Ala Local Government Area, Benue State, Nigeria

Crop yields together with economic and social benefits of farming depend in part on land management and soil quality. Soil management and cropping systems have long-term effects on agronomic and environmental functions. This study aimed at assessing soils under yam-based cropping systems for quality and suitability so as to enhance sustainable production. The study was carried out in Katsina Ala local government area of Benue state where yam is a major crop. Sixteen modal profile were dug, described for characterization and suitability evaluation. Ten cluster locations were selected and twenty soil samples randomly collected within each cluster. The soils were subjected to laboratory analyses and results subjected descriptive statistics. Suitability of the soils for yam, citrus and groundnut were evaluated using parametric approach and soil quality of the area was assessed using Relative Soil Quality Indices (RSQI). The soils encountered are sandy to silty in nature with some having plinthite at depth. The soils, classified as Alfisol, Entisol and Inceptisol are moderately (S2) to highly suitable S1) for the three crops and have moderate to high quality for crop production with percentage soil quality index ranging from 60. 37 to 74.31 %. Soils of the study site are of good quality and are suitable for production of yam, citrus and groundnut. However, because yam is a great feeder and tropical soils are fragile making them prone to degradation, there is need for maintenance of soil fertility through organic matter management for sustainable use

Phytoremediation of heavy metal-contaminated sites: Eco-environmental concerns, field studies, sustainability issues and future prospects

Environmental contamination due to heavy metals (HMs) is of serious ecotoxicological concern worldwide because of their increasing use at industries. Due to non-biodegradable and persistent nature, HMs cause serious soil/water pollution and severe health hazards in living beings upon exposure. HMs can be genotoxic, carcinogenic, mutagenic, and teratogenic in nature even at low concentration. They may also act as endocrine disruptors and induce developmental as well as neurological disorders and thus, their removal from our natural environment is crucial for the rehabilitation of contaminated sites. To cope with HM pollution, phytoremediation has emerged as a low-cost and eco-sustainable solution to conventional physico-chemical cleanup methods that require high capital investment and labor alter soil properties and disturb soil microflora. Phytoremediation is a green technology wherein plants and associated microbes are used to remediate HM-contaminated sites to safeguard the environment and protect public health. Hence, in view of the above, the present paper aims to examine the feasibility of phytoremediation as a sustainable remediation technology for the management of metals-contaminated sites. Therefore, this paper provides an in-depth review on both the conventional and novel phytoremediation approaches, evaluate their efficacy to remove toxic metals from our natural environment, explore current scientific progresses, field experiences and sustainability issues and revise world over trends in phytoremediation research for its wider recognition and public acceptance as a sustainable remediation technology for the management of contaminated sites in 21st century

Planning sustainable soil management under intensified crop production system in Nigeria: an ecosystem approach

No abstractKeywords: sustainable; management; intensified; crop production; ecosystemGlobal Journal of Agricultural Sciences Vol. 4(1) 2005: 45-5

Microbial Inoculants-Assisted Phytoremediation for Sustainable Soil Management.

Agricultural soil Pollution refers to its accumulation of heavy metals and related compounds which could be from natural or anthropogenic sources. This threatens food quality, food security and environmental health. The traditional physico-chemical technologies soil washing used for soil remediation render the land useless as a medium for plant growth, as they remove all biological activities. Others are labour intensive and have high maintenance cost. Phytoremediation, sustainable and cheaper in situ remediation techniques was therefore considered. However plants do not have the capability to degrade many soil pollutants especially the organic pollutant. It is therefore imperative to take advantage of the degrading ability of soil microorganisms. This chapter therefore focuses on phytoremediation techniques augmented by microbial inoculants