The agronomic and economic benefits of fertilizer and mulch use in highland banana systems in Uganda

Banana is the most important food crop in Uganda. However, there has been a decline in productivity, attributed to declining soil fertility, drought, pests and diseases and crop management factors. This study aimed to explore the possibility of increasing yields through the use of fertilizer and mulch, and to evaluate the benefits of these inputs across the major banana producing regions in Uganda. This study was carried out in 179 smallholder plots in Central, South, Southwest and East Uganda in 2006/7. Half of the plots were ‘demonstration plots’ of an agricultural development project, while the other half were neighboring farmer plots that acted as ‘control’. Demonstration plots received mineral fertilizer (100% of plots), averaging 71 N, 8 P, 32 K kg ha−1 yr−1 and external mulch from grass and crop residues (64% of plots), whereas control plots received no mineral fertilizer and little external mulch (26% of plots). Demonstration plots had significantly (P ⩽ 0.05) higher yields than control plot in Central, South and Southwest, but average yield increases varied from 4.8 t ha−1 yr−1 (Southwest) to 8.0 (Central), and 10.0 (South). Average weevil corm damage (3%) and nematode-induced root necrosis (7%) was low and similar for both plot types, so yield increases could only be explained by the use of fertilizer and mulch. The highest demonstration plot yield increases were observed where fertilizer addressed key nutrient deficiencies identified using the compositional nutrient diagnosis approach. Farm gate bunch prices declined from 0.17 (Central Uganda) to 0.07 USD kg−1 (Southwest Uganda). Consequently, average marginal rate of return (MRR) of fertilizer and mulch use ranged from 0.1 (Southwest) to 5.8 (Central). The technologies were likely to be acceptable to farmers (MRR ⩾ 1.00) up to 160 km away from the capital. Fertilizer use is likely to be acceptable in all regions (MRR = 0.7–9.4) if local fertilizer prices of 2006/7 (average USD 0.56 kg−1 of fertilizer) declined by 50%. Doubling of fertilizer prices is likely to make fertilizer use unacceptable beyond 100 km away from the capital. The study concludes that there is scope for increased input use in banana systems in Uganda, but that regional variations in crop response, input/output prices, and price fluctuations have to be taken into account

Agricultural extension messages using video on portable devices increase knowledge about seed selection, storage and handling among smallholder potato farmers in southwestern Uganda

Open Access JournalTo feed a growing population, agricultural productivity needs to increase dramatically. Agricultural extension information, with its public, non-rival nature, is generally undersupplied, and public provision remains challenging. In this study, simple agricultural extension video messages, delivered through Android tablets, were tested in the field to determine if they increased farmers’ knowledge of recommended practices on (i) potato seed selection and (ii) seed storage and handling among a sample of potato farmers in southwestern Uganda. Using a field experiment with ex ante matching in a factorial design, it was established that showing agricultural extension videos significantly increased farmers’ knowledge. However, results suggested impact pathways that went beyond simply replicating what was shown in the video. Video messages may have triggered a process of abstraction, whereby farmers applied insights gained in one context to a different context

Compositional dynamics of multilevel innovation platforms in agricultural research for development

Article purchasedInnovation platforms (IPs) form a popular vehicle in agricultural research for development (AR4D) to facilitate stakeholder interaction, agenda setting, and collective action toward sustainable agricultural development. In this article, we analyze multilevel stakeholder engagement in fulfilling seven key innovation system functions. Data are gathered from experiences with interlinked community and (sub)national IPs established under a global AR4D program aimed at stimulating sustainable agricultural development in Central Africa. Our findings show that all innovation systems functions required multilevel action, but that fulfillment of specific functions demands for strategic involvement of specific stakeholders at specific levels. We observed that a research- and dissemination-oriented sequence in the functions was prioritized in AR4D IPs and argue that such a sequence may be different in other types of (business) IPs. Our findings provide an incentive to think function oriented about compositional dynamics (stakeholder groups * levels) in innovation processes, rather than striving for equal stakeholder participation

Integrated Soil Fertility Management: Contributions of framework and practices to climate-smart agriculture

Updated on 13/09/2016. Integrated Soil Fertility Management (ISFM) is a set of practices related to cropping, fertilizers, organic resources and other amendments on smallholder farms to increase production and input use efficiency. ISFM delivers productivity gains, increased resilience, and mitigation benefits. ISFM benefits food security and incomes enhances yield stability in rainfed systems, and reduces greenhouse gas emissions from soils and fertilizers making it of value to climate-smart agriculture

The Role of Policy in Facilitating Adoption of Climate-Smart Agriculture in Uganda

This study aimed at understanding the influence of policy frameworks on climate change adaptation in Uganda. It combined literature review on existing natural resource management policies, focus group discussions with farming communities and interviews with key informants across various policy implementation levels. Findings reveal that even when farmers are exposed to appropriate adaptation practices, adoption is still constrained by limited enforcement of policies and regulations. Various reasons constrain enforcement; policies are formulated through top–down approaches, NGOs and local governments are minimally involved while local communities are largely excluded. There is either lack of or existence of non-functional implementation structures prescribed by the policies. Coupled with unclear roles among actors, weak links between different administration levels, limited human and financial resources and political interference, the ability of smallholders to adopt climate-smart agriculture (CSA) is thus constrained. Due to lack of knowledge of what the policies provide for, smallholders are not able to demand their rights. There is need for more focused follow-up research on specific issues raised in this report

Soil fertility gradients and production constraints for coffee and banana on volcanic mountain slopes in the east African rift: a case study of Mt. Elgon

Volcanic mountains in the East African Rift (e.g. Mt. Kenya, Mt. Kilimanjaro, Mt. Elgon) are some of the most productive agricultural regions, often dominated by coffee and banana cultivation. Consequently, these regions suffer from a high and increasing population density with a declining soil fertility status imposing pressure on the available land, which in turn results in encroaching into the national forests. This study documents the soil fertility constraints along the slopes of Mt. Elgon and explores its corresponding gradients in plant nutritional status. This research links the topography of Mt. Elgon to the prevailing soil types and their current fertility status. It reveals important relations and gradients between soil fertility parameters and its corresponding environment along the slope. Soil pH, soil available P and exchangeable K, Ca and Mg are significantly decreasing with elevation. Thereby, gradients and constraints in macro- and micro-nutrient uptake by coffee and banana are revealed along the toposequence and different altitude-specific nutrient limitations are determined for both crops. K, Mn and Si uptake in both crops is decreasing with elevation along the slope, while the Mo and Ni uptake in both crops is increasing. With increasing elevation, B uptake is only decreasing in coffee and P uptake is only decreasing in banana. In addition, the antagonistic interaction between K and Mg limits the Mg uptake of both crops in the lower areas, while in the high region the Mg uptake is simply limited by low soil availability. It follows that a general fertilizer recommendation cannot be made in these regions and that the soil fertility problems along these slopes should be specifically addressed and appropriately managed according to the local requirements

Cocoa: Driver of Deforestation in the Democratic Republic of the Congo?

The Democratic Republic of the Congo (DRC) accounts for the largest part of the Congo Basin forest: two-thirds (some 155 million hectares) are forested and 69 percent of which is dense humid forest. With a surge in world market commodity prices for cocoa in 2008 and a steady 2-5% annual increase in global demand, incentives to expand cocoa production are significant. This study determines the role of cocoa in the RDC in terms of current deforestation, identifies actors, and estimates future expansion. Although cocoa in occurs in eight regions in the DRC, authors focused on the four major growing regions in this study, using a rough estimation to get an “order of magnitude” of cocoa as a driver of deforestation. The authors found that cocoa expansion could lead to the loss of 176-395 square kilometres of forest in the next decade, strongest in the Mambasa region and in Equatorial Province surrounding Mbandaka, Bikoro and Lukolela. However, migration of internally displaced people, production of food crops, and illegal logging are likely more severe drivers of deforestation in the Mambasa region. Deforestation caused by cocoa growing in Equatorial Province will largely depend on rejuvenation of existing fields