Cassava Weed Management Data – Herbicide Screening 2014

The ‘Sustainable Weed Management Technologies for Nigeria’ was a 5-year project that was developed and assessed with smallholder farmer participation modern, relevant and appropriate cassava weed management technologies suitable for sustainable intensification in major agro-ecological (humid rainforest, forest transition savanna and southern Guinea savanna) and socio-economic conditions of Nigeria. An important goal of the project was to help smallholder cassava growers achieve sustainable increases in their productivity and incomes through the development and adoption of improved weed control methods. The project evaluated enhanced cassava agronomy, including judicious, safe use of herbicides, toward improved weed management, across 4 states in Nigeria where cassava is central to food security and livelihoods of 4.5 million farm families.

Though Nigeria is still the global leader in the overall production of cassava with about 50 million tons on 3.8 million hectares, average yields in Nigeria are only about half of those in leading countries in Asia, and less than half of those typical from researcher-run trials in Nigeria. Diverse factors are responsible for low productivity on about 4.5 million cassava farms, but poor weed management is generally among the principal factors. Weed control in the humid tropics is always a challenge, but compared to most other field crops, weed control in cassava systems is much more demanding. The crop is in the field for a long time (12 to 18 months), and is sown at wide spacing, resulting in ample opportunity for weeds to occupy space under the cassava canopy and reduce productivity. Although weeds are one of the most important constraints to improving cassava productivity; for high yields, good weed control needs to be coupled with improved varieties sown in the right densities at the right time. Adequate plant nutrition and pest control are also important; however, such inputs will not result in better yields if weeds are not controlled.

Hand weeding is the predominant weed control practice on smallholder cassava farms. Conventionally, farmers weed cassava three times, but in cassava farms where perennial weeds, such as Imperata, are predominant, extra hoe weeding may be required. Weeding takes 50 to 80% of the total labor budget. Up to 200-500 hours of labor for mostly women and children per ha are needed to prevent economic cassava root losses in Nigeria. IITA and its partners are therefore, through this project conducted research that developed innovative weed management practices, combining improved varieties, proper planting dates, plant populations, and plant nutrition, all coupled to intercropping and tillage options, through well-focused trials in the three agro-ecologies where cassava dominates in Nigeria. Herbicides, meeting globally accepted conventions and safety thresholds appropriate for smallholders, were tested for efficacy and economic merit. Multi-location on-station/off-station trials were followed with participatory farmer evaluations. Extension manuals and other tools for farmer and applicator learning were developed.

Results from this project showed that with appropriate weed management couple with best cassava agronomy cassava growers in can more than double the national yield average in Nigeria.

Cassava Weed Management Data – Agronomy Trials 2014

The ‘Sustainable Weed Management Technologies for Nigeria’ was a 5-year project that was developed and assessed with smallholder farmer participation modern, relevant and appropriate cassava weed management technologies suitable for sustainable intensification in major agro-ecological (humid rainforest, forest transition savanna and southern Guinea savanna) and socio-economic conditions of Nigeria. An important goal of the project was to help smallholder cassava growers achieve sustainable increases in their productivity and incomes through the development and adoption of improved weed control methods. The project evaluated enhanced cassava agronomy, including judicious, safe use of herbicides, toward improved weed management, across 4 states in Nigeria where cassava is central to food security and livelihoods of 4.5 million farm families.

Though Nigeria is still the global leader in the overall production of cassava with about 50 million tons on 3.8 million hectares, average yields in Nigeria are only about half of those in leading countries in Asia, and less than half of those typical from researcher-run trials in Nigeria. Diverse factors are responsible for low productivity on about 4.5 million cassava farms, but poor weed management is generally among the principal factors. Weed control in the humid tropics is always a challenge, but compared to most other field crops, weed control in cassava systems is much more demanding. The crop is in the field for a long time (12 to 18 months), and is sown at wide spacing, resulting in ample opportunity for weeds to occupy space under the cassava canopy and reduce productivity. Although weeds are one of the most important constraints to improving cassava productivity; for high yields, good weed control needs to be coupled with improved varieties sown in the right densities at the right time. Adequate plant nutrition and pest control are also important; however, such inputs will not result in better yields if weeds are not controlled.

Hand weeding is the predominant weed control practice on smallholder cassava farms. Conventionally, farmers weed cassava three times, but in cassava farms where perennial weeds, such as Imperata, are predominant, extra hoe weeding may be required. Weeding takes 50 to 80% of the total labor budget. Up to 200-500 hours of labor for mostly women and children per ha are needed to prevent economic cassava root losses in Nigeria. IITA and its partners are therefore, through this project conducted research that developed innovative weed management practices, combining improved varieties, proper planting dates, plant populations, and plant nutrition, all coupled to intercropping and tillage options, through well-focused trials in the three agro-ecologies where cassava dominates in Nigeria. Herbicides, meeting globally accepted conventions and safety thresholds appropriate for smallholders, were tested for efficacy and economic merit. Multi-location on-station/off-station trials were followed with participatory farmer evaluations. Extension manuals and other tools for farmer and applicator learning were developed.

Results from this project showed that with appropriate weed management couple with best cassava agronomy cassava growers in can more than double the national yield average in Nigeria.

Analysis of Soil Related Constraints for Sustainable Intensification

FAO estimates that agricultural intensification contributes about 80% of increased crop production in developing countries. Thus sustainable intensification (SI) will require, among other things, better use of land resources upon which production depends. This is critical given that most of the arable land in Africa has soil related problems, leading losses of nutrients and land cover (Heng et al. 2015). In this context improved land management is critical to overcoming soil related constraints to sustainable food production and in targeting agricultural interventions. However, limited availability of site-specific nutrient management guidelines for semi-arid zones in Tanzania undermines efforts to target technologies in the specific biophysical conditions in which smallholder farmers operate. Thus technologies adopted under these circumstances are risky as they may fail to address key drivers of enhanced crop production or land degradation. We characterized soils in Kongwa and Kiteto districts to assess fertility status and drivers of land degradation so as to inform the development of integrated land management options for SI under the Africa RISING project. This approach helps to link soil management recommendations to soil conditions and in targeting interventions./p>

About the project

Project title: Africa RISING- Intensification of Maize-Legume Based Systems in the Semi-Arid Areas of Tanzania to Increase Farm Productivity and Improve Farming Natural Resource Base

Project abstract

The aim of the Africa RISING project in Kongwa and Kiteto Districts, Tanzania is to provide a scientific basis for sustainably intensifying agricultural production in semi-arid areas of central Tanzania. The project activities are falls under 4 thematic areas that address three critical elements of sustainable intensification (SI), i.e. genetic, ecological and socio-economic intensification technologies. The scope of activities being implemented includes packaging of new legume and cereal varieties with over 120% yield advantage, packaging and validation of integrated productivity enhancing technologies for cereals, legumes, legume trees and soil health technologies, food safety primarily to reduce aflatoxin contamination and integration of livestock into the cropping systems. The innovation platform is used to set R4D priority in the active sites. In the 2013-2014 season, we reached out to about 1217 farmers Kongwa and Kiteto districts. In 2014 we plan to reach out to about 1500 new farmers. The project team is comprised of national partners (e.g. ARI-Hombolo, District Agricultural Officers, SUA and UDOM) and CG Partners (CIMMYT and ICRAF) under the leadership of ICRISAT.

Project website: http://africa-rising.net

Project start date: 05/1/2012

Project end date : 09/30/2016

Developing direct-seeding options for rice farmers in the Indo-Gangetic Plains

The rice-wheat farming systems of the Indo-Gangetic Plains (IGP) are essential to India’s food security. These systems face multiple threats, however, to the future of the natural resource base. These threats include increased costs for irrigation and fuel, seasonal labor shortages, and unsustainable use of groundwater. In addition, climate change means increasingly variable monsoons that are likely to pose further constraints. Direct-seeded rice, as an alternative to transplanted rice, provides a potential entry point to save labor, reduce reliance on irrigation water, and increase productivity of the wheat crop. Technology options for direct seeding and related weed management were developed and validated in India commencing with on-station experiments and small-scale on-farm trials in 2000 and increasing to a total of more than 100 farmers’ field trials by 2005. These farmers’ trials, which compared both wet and dry direct-seeded rice with transplanted rice, were conducted in the states of Uttarakhand, Uttar Pradesh, and Bihar by four agricultural universities. The trials involved a wide community of farming stakeholders in diverse agroecosystems, and spanned mechanized farms (>2 ha) in Uttarakhand to smallholder farms (>=0.5 ha) in Bihar reliant on manual labor. Direct seeding is ‘knowledge-intensive’ and farmers require access to considerable amounts of information in order to respond to the variability of the monsoon, soil conditions, and weed infestations. Making such information available within the farm communities, and providing them w
ith tools to aid better decision making and the means to evaluate their crop own management, is critical to the successful adoption of such practices. Activities with farmers’ groups have continued since 2005 to validate direct-seeding practices on-farm, and also to explore the constraints to adoption and the information requirements to support effective farmer decision making.

Replication Data for: Distributions, ex situ conservation priorities, and genetic resource potential of crop wild relatives of sweetpotato (Ipomoea batatas (L.) Lam., I. series Batatas)

Crop wild relatives of sweetpotato (Ipomoea batatas (L.) Lam., I. series Batatas) have the potential to contribute to breeding objectives for this important root crop. Uncertainty in regard to species boundaries and their phylogenetic relationships, the limited availability of germplasm with which to perform crosses, and the difficulty of introgression of genes from wild species has constrained their utilization. Here, we compile geographic occurrence data on relevant sweetpotato wild relatives and produce potential distribution models for the species. We then assess the comprehensiveness of ex situ germplasm collections, contextualize these results with research and breeding priorities, and use ecogeographic information to identify species with the potential to contribute desirable agronomic traits. The fourteen species that are considered the closest wild relatives of sweetpotato generally occur from the central United States to Argentina, with richness concentrated in Mesoamerica and in the extreme Southeastern United States. Currently designated species differ among themselves and in comparison to the crop in their adaptations to temperature, precipitation, and edaphic characteristics and most species also show considerable intraspecific variation. With 79% of species identified as high priority for further collecting, we find that these crop genetic resources are highly under-represented in ex situ conservation systems and thus their availability to breeders and researchers is inadequate. We prioritize taxa and specific geographic locations for further collecting in order to improve the completeness of germplasm collections. In concert with enhanced conservation of sweetpotato wild relatives, further taxonomic research, characterization and evaluation of germplasm, and improving the techniques to overcome barriers to introgression with wild species are needed in order to mobilize these genetic resources for crop breeding

Africa RISING Tanzania- Simulating Adoption Study

Sustainable intensification represents one of the best options for enhanced crop productivity in many fragile ecosystems. However, limited uses of sustainable production intensification technologies such as Integrated Soil Fertility Management technologies to address challenges to crop and livestock productivity including soil fertility challenge is strongly associated with declining agricultural productivity and increasing rural poverty. The Africa RISING project is being implemented in Kongwa and Kiteto districts of Tanzania to respond to challenges that hamper agricultural productivity in semi-arid of selected two districts of Tanzania using three sets of technologies. These are: (i) Integrated Soil Fertility Management technologies, (ii) physical and biological barriers for erosion control through adoption of tie ridges locally known as ’fanya juu’/ ‘fanya chini’; iii) physical barriers for erosion control (ripping and tied-ridging) and enhancing range, lands and livestock productivity.It has been known for long time that the success of any project depends, in part, on whether farmers adopt the offered technologies and, if they do, whether those farmers adopt the technologies in an ideal combination, and for the prescribed length of time needed to produce designed results. While studying the adoption of technologies after a project has ended has been a common practice, the well-established adoption theory and literature explain the importance of studying and predicting adoption in the early stage of the project in fostering a more complete understanding of the attributes of technologies and how they influence adoption and diffusion which in turn helps to allow the attributes of the technologies or the extension strategy to be modified so that levels of adoption and diffusion can be improved. Therefore, the adoption study was conducted to simulate adoption peak level of technologies to guide scaling up decisions and implementation strategy.

About the project

Project title: Africa RISING

Project abstract


The aim of the Africa RISING project in Kongwa and Kiteto Districts, Tanzania is to provide a scientific basis for sustainable intensifying agricultural production in semi-arid areas of central Tanzania. The project activities are falls under 4 thematic areas that address three critical elements of sustainable intensification (SI), i.e. genetic, ecological and socio-economic intensification technologies. The scope of activities being implemented include: packaging of new legume and cereal varieties with over 120% yield advantage, packaging and validation of integrated productivity enhancing technologies for cereals, legumes, legume trees and soil health technologies, food safety primarily to reduce aflatoxin contamination and integration of livestock into the cropping systems. The innovation platform is used to set R4D priority in the action sites. In the 2013-2014 season, we reached out to about 1217 farmers Kongwa and Kiteto districts. In 2014 we plan to reach out to about 1500 new farmers. The project team is comprised of national partners (e.g. ARI-Hombolo, District Agricultural Officers, SUA and UDOM) and CG Partners (CIMMYT and ICRAF) under the leadership of ICRISAT.

Project website: http://africa-rising.net

Project start date: 05/01/2012

Project end date : 09/30/2016

Replication Data for: Crop wild relatives of pigeonpea (Cajanus cajan (L.) Millsp.): Distributions, ex situ conservation status, and potential genetic resources for abiotic stress tolerance

Pigeonpea (Cajanus cajan (L.) Millsp.) is a versatile, stress-tolerant, and nutritious grain legume, possessing traits of value for enhancing the sustainability of dry sub-tropical and tropical agricultural systems. The use of crop wild relatives (CWR) in pigeonpea breeding has been successful in providing important resistance, quality, and breeding efficiency traits to the crop. Current breeding objectives for pigeonpea include increasing its tolerance to abiotic stresses, including heat, cold, drought, and waterlogging. Here we assess the potential for pigeonpea CWR to be further employed in crop improvement by compiling wild species occurrence and ex situ conservation information, producing geographic distribution models for the species, identifying gaps in the comprehensiveness of current germplasm collections, and using ecogeographic information to identify CWR populations with the potential to contribute agronomic traits of priority to breeders. The fifteen prioritized relatives of pigeonpea generally occur in South and Southeast Asia to Australia, with the highest concentrations of species in southern India and northern Australia. These taxa differ considerably among themselves and in comparison to the crop in their adaptations to temperature, precipitation and edaphic conditions. We find that these wild genetic resources are broadly under-represented in ex situ conservation systems, with 80% of species assessed as high priority for further collecting, thus their availability to plant breeders is insufficient. We identify species and highlight geographic locations for further collecting in order to improve the completeness of pigeonpea CWR germplasm collections, with particular emphasis on potential traits for abiotic stress tolerance

Replication Data for How to be an ant on figs

Mutualistic interactions are open to exploitation by one or other of the partners and a diversity of other organisms, and hence are best understood as being embedded in a complex network of biotic interactions. Figs participate in an obligate mutualism in that figs are dependent on agaonid fig wasps for pollination and the wasps are dependent on fig ovules for brood sites. Ants are common insect predators and abundant in tropical forests. Ants have been recorded on approximately 11% of fig species, including all six subgenera, and often affect the fig–fig pollinator interaction through their predation of either pollinating and parasitic wasps. On monoecious figs, ants are often associated with hemipterans, whereas in dioecious figs ants predominantly prey on fig wasps. A few fig species are true myrmecophytes, with domatia or food rewards for ants, and in at least one species this is linked to predation of parasitic fig wasps. Ants also play a role in dispersal of fig seeds and may be particularly important for hemi-epiphytic species, which require high quality establishment microsites in the canopy. The intersection between the fig–fig pollinator and ant–plant systems promises to provide fertile ground for understanding mutualistic interactions within the context of complex interaction networks.

Community Based Seed Multiplication

This data study contains field trial data on crop management, yield, farmers field school (FFS) attendance.


About the project

Project title: Decentralized System for Community-Based Seed Production and Extension Provision

Project abstract


Unavailability of quality seed of commonly grown crops was one of the priority constraints to increased agricultural productivity identified during the PCA. It is the aim of this activity to develop a system whereby this bottleneck can be addressed in a sustainable manner, as far as possible relying on private initiative and community interest rather than be dependent on extension / input support provided by BoAs line agencies and/or NGOs. The approach will work closely with the Model/Lead Farmer concept (1 to 5) which is widely promoted by the GoE with a Farmer Field School (light) approach, that promotes farmer-to-farmer extension.

Project website: http://africa-rising.net

Project start date: 01/01/2014

Project end date : 06/01/2015

Characterization of Maize Producing Households in Drought Prone Regions of Eastern Africa

Agriculture in eastern Africa is predominantly rainfed and maize is a major food crop, primarily produced for home consumption and the market by small-scale family farms. The study characterized farm households in the drought prone maize growing areas of eastern Africa synthesizing data from parallel household surveys in Ethiopia, Kenya, Uganda and Tanzania. The study provides a comparative analysis of the farm households’ assets, livelihood strategies and crop management practices, with an emphasis on maize and maize seed. This illustrates how farmers in a similar agro-ecological environment but with different socio-economic and institutional settings have variously adapted to living with drought and how the inherent weather risk co-determines the livelihood portfolio, agricultural intensification incentives and system development pathways. The study thereby illustrates the challenges for agricultural intensification in such drought prone environments and the scope for drought tolerant maize varieties and explores the research and development implications.