Grazing reserves in Nigeria: Problems, prospects and policy implication

Grazing reserves in Nigeria are areas set aside for the use of pastoralists and are intended to be the foci of livestock development. The stated purpose of grazing reserves is the settlement of nomadic pastoralists they offer security of tenure as an inducement to sedentarization through the provision of land for grazing and permanent water. This paper reviews problems associated with grazing reserves and offers suggestions to make them more productive and relevant to the needs of the intended beneficiaries. Although based on experience in grazing reserves in the subhumid zone of Nigeria, some of the conclusions should be applicable elsewhere

Integrated crop-livestock systems - A key to sustainable intensification in Africa

Mixed crop-livestock systems provide livelihoods for a billion people and produce half the world’s cereal and around a third of its beef and milk. Market orientation and strong and growing demand for food provide powerful incentives for sustainable intensification of both crop and livestock enterprises in smallholders’ mixed systems in Africa. Better exploitation of the mutually reinforcing nature of crop and livestock systems can contribute to a positive, inclusive growth trajectory that is both ecologically and economically sustainable. In mixed systems, livestock intensification is often neglected relative to crops, yet livestock can make a positive contribution to raising productivity of the entire farming system. Similarly, intensification of crop production can pay dividends for livestock and enhance natural resource management, especially through increased biomass availability. Intensification and improved efficiency of livestock production mean less greenhouse gases per unit of milk and more milk per unit of water. This paper argues that the opportunities and challenges justify greater investment in research for development to identify exactly where and how ‘win-win’ outcomes can be achieved and what incentives, policies, technologies and other features of the enabling environment are needed to enable sustainable, integrated and productive mixed crop-livestock system

An approach for the evaluation of herbaceous legumes with multiple benefits

In order to promote the identification of herbaceous legumes that may contribute to weed control, soil fertility, crop production, and livestock enterprises, as a means of encouraging sustainable agricultural practices amongst resource-poor farmers, an evaluation method using a simple sampling approach is described. To illustrate the method, result from one experiment in the derived savanna of Nigeria conducted over a period of 2.5 years are presented. The experiment included 14 accessions of single legume species, 9 mixtures of species, and 4 grain-legume accessions (soybean and cowpea). Mixtures of species, including combinations of rapidly establishing and slowly establishing but more persistent species, were designed to stabilize yield and minimize the risk involved in introducing herbaceous legumes. Although the biomass production of the mixtures was less than the best single species, they did remain stable over the evaluation period. Whilst the rapidly establishing species disappeared from the mixtures after the establishment year, the other components were able to compensate for this, and mixtures had relatively stable yields throughout the period. Grain legumes produced substantial biomass only during the establishment year, but have the potential to contribute to systems where farmers' circumstances permit the use of inputs. Such variations, together with those relating to speed of establishment, biomass production, and persistence over the evaluation period, are discussed with respect to the need to identify species or mixtures that are suitable for farmers' socioeconomic circumstance as well as biophysical conditions

Soil fertility management and cowpea production in the semi arid tropics of West Africa

Cowpea (Vigna unguiculata[L.] Walp.) is an important grain legume in the semi- arid zone of West Africa as it is a major source of dietary protein for the people. It is usually grown as an intercrop with the major cereals, namely millet and sorghum. Despite its importance, its yields are very low due to several constraints including poor soil, insect pests, and drought. The soils in semiarid West Africa are inherently low in nitrogen and phosphorus. Soil, water, and nutrient management practices are inadequate to sustain food production and to meet the food requirements of the fast growing population. Research results show that proper management of organic amendments such as crop residues and manure, which are essential complements to mineral phosphorus fertilizers, can increase yields of cowpea and associated cereals more than three fold. Direct application of indigenous phosphate rocks can be an economical alternative to the use of imported, more expensive soluble phos- phorus fertilizers for cowpea production in the region. The agronomic effectiveness of indigenous phosphate rock is about 50% compared to the imported single super- phosphate. Furthermore, when the unreactive phosphate rocks are partially acidu- lated at 50%, their agronomic effectiveness can increase to more than 70%. Stud- ies on cereal–cowpea rotation revealed that yields of cereals succeeding cowpea could, in some cases, double compared to continuous cereal cultivation. With efficient soil fertility management, cowpea can fix up to 88 kg N/ha and this results in an increase of nitrogen use efficiency on the succeeding cereal crop from 20% in the continuous cereal monoculture to 28% when cereals are in rotation with cowpea. Furthermore, the use of soil nitrogen increased from 39 kg N/ha in the continuous cereal monoculture to 62 kg N/ha in the rotation systems. Future research needs to focus on understanding the factors affecting phosphorus uptake from different sources of natural rock phosphate. There is also a need to quantify the below-ground nitrogen fixed by different cowpea cultivars. The increase of cowpea productivity in the cropping systems in this region will improve the nutri- tion of people, increase the feed quantity and quality for livestock, and contribute to soil fertility maintenance. This should contribute to reduction in poverty and environmental degradation

Pathways for sustainable development of mixed crop livestock systems: Taking a livestock and pro-poor approach

Mixed crop livestock systems provide the majority of the cereal and livestock domestic products for households in developing countries. We explore the question of whether such systems can respond to increasing demands for livestock products without compromising future livelihoods of the poor or the environment. We consider how the potential of smallholder farmers to address future milk and meat demands as livestock system transition may be impacted by the trajectory of intensification, the type of livestock commodity and the changing economic circumstances. Examples of ruminant feeding and management options with the potential to increase productivity and mitigate negative environmental impacts, notably greenhouse gases and the use of land and water in the context of developing country crop livestock systems are presented. However, such technical dimensions need to be realistically and practically considered in the context of changing market demands. Furthermore, if crop livestock systems in developing countries are to benefit today's smallholder farmers, radically different approaches will be needed. Equal importance will need to be given to technology based production and efficiency enhancing dimensions together with innovative and practical approaches encompassing institutional, policy and market solutions often in a value chain contex

Differences in the effects of temperature and photoperiod on progress to flowering among diverse Mucuna spp

The use of Mucuna spp. in cover crop and green manure technologies is proving to be successful in the tropics and subtropics following intensive efforts in technology transfer to farmers by NGOs (Non‐Governmental Organizations). This includes the transfer of seeds of Mucuna spp. for which the range of adaptation and the effect of environment on crop phenology are poorly understood. A selection of Mucuna spp. germplasm was evaluated over a range of contrasting photothermal conditions in controlled‐environment glasshouses. Dates of emergence and first flowering were recorded. Where possible, triple‐plane rate of development models were fitted to the first flowering data to quantify the relative sensitivity of each species to photoperiod and temperature. All accessions showed short‐day responses but there were substantial differences in the sensitivity of rate of progress to first flowering to environment, particularly to photoperiod. This results in differences in maturity period between accessions which, with appropriate understanding, could be functionally exploited by NGOs and NARS. However, if ignored, it could result in the promotion and use of accessions ill adapted to the environment in which they are tested. In consequence there might be unnecessary resistance from farmers to the adoption of green manure and cover crops technologies which are vital to the design and maintenance of sustainable farming systems in low‐income countries in the tropics

Forage legumes for soil productivity enhancement and quality fodder production

Ruminant performance in the tropics, as in the Northern Guinea Savanna of Nigeria, is affected by seasonal variation in the availability and quality of pasture, and supplementation of animal feeds in these systems is constrained by the high price of imported inputs. Also, for farming systems in the subhumid zone of West Africa, nitrogen is generally the most limiting nutrient for crop production, and this problem has been compounded in recent decades by the difficulties faced by farmers in obtaining N fertilizers. The integration of forage legumes into the cropping cycles in the NGS of Nigeria could have the potential to enhance yields of subsequent crops through the increase in plant available N and organic carbon in the soil, as well as quality fodder for feeding livestock in the zone. Following the investigation of this, results obtained show that that Macrotyloma uniflorum and Centrosema pascuorum treatments resulted in lower bulk density than the other legume treatments for the two years. Also following one year cropping, Aeschynomena histrix/maize intercrop showed 64% increase in soil organic carbon, and was followed by Stylosanthes hamata/maize (30%), and sole A. histrix (20 %). Planting of Lablab (black seed), intercrop of Chaemacrista rotundifolia, M. uniflorum, Lablab and A. histrix with maize could result in over 100% soil N improvement within one year. The intercrop of M. uniflorum with maize resulted in higher maize grain yield than the sole maize, over the period 2000 to 2002. As much as 2.50 t ha-1 of maize stover could be obtained after planting forage legumes/maize for two years and this could be mixed with as much as 15 t ha-1 of legume residues to produce quality fodder for supplemental feeding of livestock especially in the dry seasons when livestock feed is scarce. Both maize and legume grains, and quality fodder could be sold for cash returns to the farmer, thus improving the farmers’ income from farming

Optimizing the contribution of cowpea to food and fodder production in croplivestock systems in West Africa

Cowpea is important for the provision of both grain for food and fodder for livestock but there is often a trade-off between productions of two. To better understanding influences on grain and fodder production, and how these may be influences on grain and fodder production, and two these may be utilized, research was conducted at 5 location in west Africa using 12 cowpea varieties, with and without insecticide spray. Spraying had a dramatic effect on grain production, but less so for fodder, however there was an effect of spraying on fodder quality in term of insacco digestibility at Niamey. Accessions with the potential to produce grain and fodder with good quality were identified (IT89KD-39I and TVU 12349) and studies are continuing to optimize the contribution of such material to local production system

Adaptation of the CROPGRO growth model to velvet bean (Mucuna pruriens) : II Cultivar evaluation and model testing

Velvet bean (Mucuna pruriens (L.) DC. cv.-group utilis) is widely promoted in tropical and sub-tropical regions as a green manure cover crop that can reduce weed growth and soil erosion and enhance soil fertility. To provide these benefits, the crop must attain rapid ground cover and develop substantial aboveground biomass. To assist biophysical targeting of the crop to environments that can provide adequate growth conditions, the CROPGRO model was adapted to simulate velvet bean growth and development. This paper evaluates the performance of the model for phenology, growth, senescence and N accumulation for multiple locations that represent a range of environmental and agronomic management scenarios. Vegetative development, as described by main stem leaf appearance rate, varied linearly with thermal time. Time to flowering showed departures from the linear photoperiod response used in the model. Additional research is required to determine whether the crop is influenced by factors besides photoperiod and air temperature, especially water and nutrient deficits. The linear response to photoperiod did, however, provide reasonable values for partitioning to vegetative, reproductive and senesced materials. Simulation of nitrogen concentration for various plant components matched observed data. Sensitivity analyses evaluating the ability of the crop to provide ground cover, intercept light and develop adequate growth for soil protection and weed suppression indicated that a mean temperature of over 22 °C and a soil moisture holding capacity of at least 100 mm are required. The CROPGRO model proved to be a reliable decision support tool for guiding analyses of velvet bean response to crop management and environmental conditions. Further research, however, is warranted to improve its predictive capability, especially for phenology