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The soils of South western Nigeria are rapidly degrading due to nutrient mining, soil loss, inappropriate land use, low inherent soil fertility coupled with adverse effects of climate change. These have resulted to persistent low yields and farmers' poverty. The current farming systems have failed to improve continuous decline in crop production. There is need for integrated approach that involves mineral fertilizer, organic resources, and improved crop varieties with sound agronomic practices if the region will be able to feed its population of over 35 million people. Integrated Soil Fertility Management (ISFM) is an all-encompassing resource management technique that embraces the use of good planting materials, with appropriate organic and/or inorganic fertilizer application or their integrated use. It also entails adapting the various combinations of the ISFM components to local conditions which by implication means site specific management. There is lack of coordinated information about the components of ISFM being used in SWN and most stakeholders have not appreciated the importance of integrated approach. This paper is therefore put forward to review the status of Integrated Soil Fertility Management in South western Nigeria in order to identify knowledge gap for sustainable crop production in the region. Contribution/ Originality:This study contributes in existing literature on integrated soil fertility management for sustainable crop production in southwestern Nigeria. The study also harmonizes research findings about ISFM thereby making information available for researchers, policy makers, extension agents and other stakeholders about ISFM protocols. It aids in identifying knowledge gaps for intervention. INTRODUCTIONThere is lack of coordinated information about the status of ISFM in Southwestern Nigeria (SWN). Several studies have been carried out about components of ISFM but optimal and sustainable crop production have not been attained by farmers. The aim of this paper therefore is to review the level of ISFM integration into production systems, identify constraints and knowledge gap and make recommendation for sustainable increase in the quantity

Application of manure for soil amendment plays important roles in reclaiming and improving soil properties of degraded soils. This study assessed the effects of composted and non-composted manures on a degraded soil under continuous maize production. The treatments applied consisted of composted manures in form of cassava based compost (CBM) and verticompost (VC) at the rate of 0, 30, 60 and 120 tons/ha, non-composted manure (NC) applied as poultry manure (PM), and an un-amended control plot. These treatments were laid out in a randomized complete block design replicated three times. Soil physical and chemical properties were determined for two consecutive seasons, with maize (SUWAN 1-SYR) planted as test crop. The CBM, VC and PM treatments increased the soil organic carbon content by 18.2, 24.1, and 22.3 % respectively. Corresponding increases observed in cation exchange capacity (CEC) were 13.6, 15.7, and 15.2 %. The comparison of the soil chemical properties measured indicated positive effects from the amendments on the soil properties in the order: CBM < PM < VC.  The maize grain yield of cassava based fertilized plot consistently and significantly was higher than the other treatments in both cropping seasons. However, both the composted and non-composted manures favored improved maize growth and resulted in higher grain yields (4.62 – 6.03 t ha-1) than the un-amended control treatment (3.69 t ha-1). The study therefore showed that the incorporation of manures, whether composted or non-composted, is beneficial to soils, improving one or more essential soil attributes thus reducing soil degradation.

Conservation of soil moisture is one of the major limiting factors to crop production. Improvement of soil physical properties could enhance soil moisture conservation, improve crop productivity and reduce food insecurity in sub Saharan Africa. A field study was carried out to determine the effects of 3 plant densities (33333, 66667 and 83333 plants/ha)on soil properties and water loss through evaporation from soils under 2 cultivars of Arachis hypogaeaL. (SAMNUT 10 and SAMNUT 21) and Arachis pintoi(PINTOI) in Ibadan, south western Nigeria. The experiment was a split plot in randomized complete block design with Arachis varieties as the main plot and plant densitiesas subplot with three replications. Data were collected on daily soil water evaporation, bulk density, saturated hydraulic conductivity, particle size, total porosity and permeability. The Soil was loamy-sand and marked reductions in soil water evaporation were observed in surfaces under Arachis varieties compared to bare soil. Reductions in soil water evaporation were 44.5%, 41.1% and 34.7% under SAMNUT 21, PINTOI and SAMNUT 10 respectively. Significant (p= 0.05) improvement on soil structure and hydraulic conductivity was observed under Arachis varieties. Plant density of 66667 plants/ha showed the best positive effect on the improvement of soil physical structures. The cultivation of SAMNUT 21at 66667 plants/ha and PINTOI at 83333 plants/haalong with other measures of sustainable soil water conservation are recommended.Key words: Arachis species, Plant densities, Evaporation,Soil hydrological properties, Food insecurity.