An action research process was conducted with communities in Gununo, southern Ethiopia (2000–2003), to develop alternative cropping strategies for achieving their food security and cash needs. Farmers identified three major production objectives depending on their household priorities and socio-economic status. In Group I, farmers are currently food insecure and want to produce enough food from their own farms. In Group II, they produce enough food but want to fulfil their financial needs. In Group III, farmers rely on off-farm activities and want to increase cash income. The current system mostly fulfils the nutritional requirement of Group II. Groups I and III were highly food deficit from their own farms, with production covering less than seven months per year and fulfilling <50% of the recommended daily allowances (RDA) for human nutrition. Using a linear programming optimization model, it was possible to fulfil the RDA of Group I by reallocating the cropping area of maize, sweet potato, coffee and wheat to potato, enset and kale in proportions of 50, 29 and 15%, respectively. To satisfy both financial and nutritional needs of Group II, an increase in the proportion of coffee and beans by about 29 and 7.3%, respectively, over the current land allocation was needed. This shift would triple their cash income. The cash income of Group III increased four-fold by full replacement of the cereals and root crops by coffee (48%) and teff (52%), though the total income was not enough to secure food security due to their small landholdings. In farms of Groups I and II, the shift to the suggested cropping will reduce soil erosion by about 40%, while it will have no effect on farms of Group III. This shift will reduce the quantity and quality of livestock feed, except for Group I. Moreover, it will increase the farm crop water requirement 17.5 and 37% in Groups I and III (resource poor households) and reduce it in resource rich households of Group II. These changes did not imply extra labour in any groups. Whilst this model can optimize systems for food security and cash income, its research for development value is in identifying possible intensification strategies for farming systems and their implications on the farming systems, rather than generating practical recommendations for all cropping systems.

Crop bioengineering provides unique and dramatic opportunities for international agricultural development. However, we consider the technology not as a ‘silver bullet’ or panacea for crop improvement in the developing world but as an increasingly important tool that can be used to complement conventional methods of crop improvement. The number of bioengineered crops ready for commercial release in developing countries is expected to expand considerably in the next few years. But the multi-national life sciences companies that are leading the research, development and commercialization of bioengineered crops focus primarily on major crops that have high commercial value and extensive international markets. These companies also hold proprietary gene technology for many other crops of extreme importance to subsistence and resource-poor farmers but do not pursue product development and commercialization because of low anticipated returns. Such crops have traditionally been overlooked and are sometimes referred to as ‘orphan crops’ because of the relative lack of research and development applied to them. We propose a strategy for the development and delivery of bioengineered crops, including orphan crops, for developing countries. Consulting local public and private sector stakeholders to determine their highest priority needs for agricultural products is the first step. This ensures local stakeholder buy-in and that we do not invest in technology that is unlikely to be adopted. Next, the feasibility of developing and delivering the product is assessed. If the result is positive, the work is organized into ‘product commercialization packages’ (PCPs) that integrate all elements of the research, development and commercialization processes. The main elements of each PCP include (i) technology development; (ii) policy-related issues such as intellectual property and licensing, as well as gaining regulatory approval by the relevant national authorities; (iii) providing public information to producers and consumers about the benefits, risks and correct management of these new products; and (iv) establishing, or verifying, the existence of marketing and distribution mechanisms to provide farmers access to planting material. Our strategy involves integration of needs-based capacity building, socio-economic impact studies and product stewardship into each PCP. Whenever appropriate, opportunities are sought to create public–private partnerships to help leverage public funds, help absorb development costs and provide a broader distribution channel. To illustrate how our strategy is being translated into action we include, as a case study, examples of work by the US Agency for International Development-funded, Cornell University-led Agricultural Biotechnology Support Project II on the research, development and delivery of bioengineered fruit and shoot-borer-resistant eggplant varieties (Solanum melanogena) for South and Southeast Asia.

Potato is an important source of food and income in the highlands of East Africa. Identification of superior genotypes for improved agronomic characteristics will enhance tuber yield. Seven promising clones from population B potato selections (quantitative resistance to late blight) obtained from the International Potato Center, two genotypes from population A (qualitative resistance) and three control cultivars were evaluated for three cropping seasons at four locations in western Uganda in order to determine performance and yield stability. The additive main effects and multiplicative interactive (AMMI) model was used for the analysis. The analysis of variance of yield data for genotypes × locations, genotypes × seasons and genotypes × locations × seasons was significant (p < 0.05) showing the variable response of genotypes and the need for stability analysis. The AMMI statistical model showed that the most stable genotypes were 392618.250 (B5) and 392127.270 (B6) (high yield) and 392618.256 (B1), 391049.255 (B2) and 392127.256 (B7) (low yield) and had negligible interactions with the environments. Across environments, the ranking of genotypes for tuber yield was not consistent. The clones 381471.18 (A2), 387121.4 (A1) and cultivar Victoria had high average yields, but these yields were below average in a few environments. Selective deployment of cultivars can improve tuber yield in the highland tropics.

Note: Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation for endorsement by the US Department of Agriculture, Makerere University or Kachwekano Agricultural Research and Development Center.

Growth and photosynthetic performance of banana (Musa sp.) grown in three levels of natural shade (33, 55 and 77% reduction in incoming radiation) were compared to an unshaded control treatment. Net CO2 assimilation rates generally decreased with increasing shade. Chlorophyll fluorescence revealed short-term dynamic photoinhibition under high light conditions but no evidence of sustained photoinhibitory damage to photosystem II. Dynamic photoinhibition decreased with increasing shade, with the greatest depression in the variable to maximal fluorescence ratio (Fv/Fm) occurring in unshaded plants during the middle of the day. Specific leaf area and leaf area ratio increased proportionately with increasing shade, whilst the chlorophyll a/b ratio decreased, reflecting a greater efficiency of light utilization under shady conditions. The optimum shade level for photosynthetic productivity would be one at which the level of photosynthetic photon flux density (PPFD) is high enough to saturate CO2 assimilation but low enough to induce shade acclimation and to reduce photoinhibition. Under the conditions studied here, the saturation level of PPFD was around 1000 μmol m−2 s−1, a light level typical of the tree-based intercropping systems in which banana is commonly grown in the tropics.

Since the Green Revolution, the public-sector's agricultural research strategy for increasing food crop productivity has been explicitly based on the premise that technology can cross political and agro-climatic boundaries, primarily through the ‘training and visit’ system of extension (also known as ‘transfer of technology’ and the ‘pipeline’ model). Today, a different strategy is emerging. Efforts to develop the necessary institutional capacity for more client-oriented participatory research, particularly in plant breeding, are now a central part of the public-sector agricultural research strategy. Greater use of participatory and gender-analysis approaches in agricultural research has significant conceptual and methodological implications for impact assessment and institutional learning.

In the Sahelian zone of Niger, there is a need to develop guidelines for integrated nutrient management, which relies on the potential nutrient sources of manure, pearl millet residue and mineral fertilizers. A fully factorial on-station experiment was conducted during the 1994 and 1995 rainy seasons at Sadoré, Niger, combining application of: (i) broadcast millet residue (300, 900 and 2700 kg ha−1), (ii) broadcast cattle manure (300, 900 and 2700 kg ha−1) and (iii) mineral fertilizer (unfertilized control, 15 kg N ha−1 + 4.4 kg P ha−1 and 45 kg N ha−1 + 13.1 kg P ha−1). Manure and fertilizer increased millet yields in both years whereas residue was effective in 1995 only. The effect of manure and residue were additive, as was the effect of manure and fertilizer but only up to 50 kg N ha−1. However in 1995, the response to fertilizer was approximately doubled in the presence of 900 or 2700 kg residue ha−1 compared to fertilizer with 300 kg ha−1 residue, indicating a strong synergistic effect. This synergistic effect was reflected in the partial factor productivity of nitrogen and phosphorous in both years. Two treatment combinations stand out as particularly relevant based on yield, partial factor productivity and nutrient balance criteria: 2700 kg manure ha−1 combined with (i) 300 kg residue and no fertilizer (95% grain yield increase); (ii) 900 kg residue ha−1 and 15 kg N + 4 kg P ha−1 (132% grain yield increase). There is a need for similar, long-term experiments to confirm the present results.

This paper presents the results of a study that was undertaken to assess adoption dynamics of Tithonia diversifolia in Siaya and Vihiga districts of western Kenya from 1997 to 2004. The study was undertaken among a random sample of 120 farmers from eight pilot villages exposed to the technology. Descriptive statistics and a logit regression model were used to analyse data. The findings show that more farmers in pilot villages of Siaya are taking up the use of Tithonia than in Vihiga. As of 2004, 52% of farmers in Siaya were adopters compared to only 8% in Vihiga. Results of the logit regression model show that the use of Tithonia biomass for soil fertility management (SFM) is more likely to be adopted in a context where there is a scarcity of animal manure, farmers are willing to plant it on farms and hire casual labour. The use of Tithonia by smallholder farmers for SFM is therefore a promising low-cost option that can be scaled up to areas where farmers face similar constraints.

An on-farm trial was conducted in the northern Guinea savanna of Nigeria, over a period of five years, with the objectives of quantifying the effects on maize of applying cattle manure in combination with synthetic fertilizer with regard to soil characteristics, yield, plant nutrition and profitability. Maize grain yield was significantly increased by the annual application of cattle manure, compared to maize receiving an equal amount of N through synthetic fertilizer, but only from the third year of the experiment. The application of manure resulted in higher soil Kjel N, Bray-I P and exchangeable K values, and an increased N utilization efficiency by maize, suggesting that yield-limiting factors other than N deficiencies were of lesser importance than in the treatment receiving sole inorganic fertilizer. Nutrients other than N applied via the manure, particularly P, K and/or B, may have contributed to the higher grain yields in treatments receiving manure. A partial budgeting analysis revealed that, over a 5-year period, investments in the application of manure, in combination with synthetic fertilizer, resulted in higher margins than the application of fertilizer alone. However, analyses of marginal rates of return of changes from low urea N to high urea N or additional manure applications suggested that it was more profitable to invest in additional urea than in organic manure in the first two years of the experiment. The results suggested that manure applications, even when applied at relatively high rates, did not serve as a quick fix to on-farm soil fertility problems, but over a longer period, manure applied in combination with synthetic fertilizers did provide a significant and profitable contribution to enhanced cereal production.

Scores of assessments of the impacts of agricultural research have been carried out over the years. However, few appear to have been used to improve decision making and the effectiveness of research programmes. The Institutional Learning and Change (ILAC) Initiative emerged within the Consultative Group on International Agricultural Research (CGIAR), with the goal of strengthening learning from experience and using lessons to improve pro-poor innovation. It is testing approaches for expanding the contributions of impact assessment and evaluation to learning, decision making and improvement.

Internal browning disorders, including brown fleck (BF), in potato (Solanum tuberosum) tubers greatly reduce tuber quality, but the causes are not well understood. This is due, in part, to the highly variable data provided by visual value-based rating systems. A digital imaging technique was developed to quantify accurately the incidence of internal browning in potato tubers. Images of tuber sections were scanned using a flatbed scanner and digitally enhanced to highlight tuber BF lesions, and the area of affected tissue calculated using pixel quantification software. Digital imaging allowed for the determination of previously unused indices of the incidence and severity of internal browning in potato tubers. Statistical analysis of the comparison between digitally derived and visual-rating BF data from a glasshouse experiment showed that digital data greatly improved the delineation of treatment effects. The F-test probability was further improved through square root or logarithmic data transformations of the digital data, but not of the visual-rating data. Data from a field experiment showed that the area of tuber affected by BF and the number of small BF lesions increased with time and with increase in tuber size. The results from this study indicate that digital imaging of internal browning disorders of potato tubers holds much promise in determining their causes that heretofore have proved elusive.

This paper argues that opportunities for reducing poverty, improving social justice, and influencing policy and institutional changes are being missed as a result of not learning enough from situations where positive changes in development indicators have already taken place. After a review of research on monitoring and evaluation (M&E), positive deviance and studies of ‘success' stories, three case studies of positive change are presented. These are the spread of bamboo tubewell irrigation in Bihar, changes in agricultural research and extension policy in Nepal, and the spread of groups and group-based organizations/federations in Nepal. General lessons include: (1) effective institutional innovation is always new and social arena specific, (2) many opportunistic social entrepreneurs are always present in arenas of positive social change, and (3) there is always purposive selection of what to observe, what to measure and what to publicize. Practical implications include: (1) strengthening social science research on understanding change in agricultural and natural resources systems, (2) selecting people for research and development intervention situations based not only on technical competence but also a track record of interest in social justice development principles, and (3) strengthening a broader concepts reflection and learning within current research and development interventions chan is currently practiced. While learning from the positive is a simple idea, it is always challenging to implement as it inevitably questions the histories, past explanations and perceptions of some scientists and development planners, especially those who promote a mainstream, formulaic approach to the design and promotion of best policies and best practices, and a simplistic, non-political/cultural approach to the transfer and scaling out and up of technology and institutional models.

A long-term field experiment was conducted at the Qu-Zhou experimental station, China Agricultural University to study how the nematode community structure was influenced by compost and chemical fertilizer, using no amendment as the control. Soil samples were collected from 0–10 cm and 10–20 cm depths. The different treatments led to a significant difference in the total number of nematodes, bacterivores, plant parasites, omnivores-predators and nematode richness. The total number of nematodes, bacterivores, omnivores-predators and nematode richness were found to decrease in chemical fertilizer-treated plots. Although plant parasites were more abundant under compost treatment than under chemical fertilization, the relative abundance of plant parasites in the compost-treated plots was smaller. The application of chemical fertilizer decreased the number of genera of bacterivores and omnivores-predators. The numbers of total nematodes, bacterivores, plant parasites and omnivores-predators were significantly positively correlated with the contents of total organic carbon, total N, alkali-hydrolysable N, available P and available K. The compost-treated plots tended to have a greater diversity of nematodes than chemical fertilizer treated plots, so there was a healthy soil ecosystem under compost treatment.

For 50 years, ‘hybrid vigour’ in crosses involving genotypes collected from the centre of diversity of the crop in the Peruvian Amazon has been the guiding principle of cocoa breeding. In the work described here, six Amazonian genotypes and one Trinitario clone were used to produce four bi-parental crosses. Twenty-two plants of each cross were propagated from plagiotropic buds as ‘cloned seedlings’ and evaluated for growth, yield and yield efficiency (the ratio of yield to continuing vegetative growth) in replicated trials in comparison with the parental clones and the reproduced seedling family. The reproduced seedling families grew faster than and outyielded all the clones in all four crosses, although they showed no gain in yield efficiency. The vigour and yield of the ‘cloned seedlings’ of the three inter-Amazon crosses exceeded mid-parent value (MPV), but not the single Trinitario cross. The pattern of departures from MPVs was inconsistent with current understanding of the genetic distance between the parents. The superiority of the seedlings over the ‘cloned seedlings’ is interpreted as an epigenetic effect. The results suggest that simple recurrent selection is an appropriate breeding strategy in cocoa, with different optimum planting densities for the seedling and clonal phases. It is concluded that if the concept of very large ‘hybrid vigour’ did not already exist in cocoa, it would not be adopted on the evidence of this work, the first in which clones were compared to their progeny grown as clones.

Bambara groundnut (Vigna subterranea) is a grain legume crop, which is increasingly popular as food in rural areas across the African continent. However, reliable information pertaining to management of the crop is limited. Field experiments were conducted in Swaziland in the 1998/99 and 1999/2000 cropping seasons to determine the influence of sowing date and environmental factors on the growth, development and yield of bambara groundnut. In the 1998/99 season, seeds of one local landrace were sown on six dates between mid-September 1998 and mid-February 1999. In 1999/2000, seeds of two local landraces were sown on six dates between mid-October 1999 and late January 2000. The highest pod yield and total dry matter production were achieved in November sowings, with maximum pod yields of 1.3 and 0.64 t ha−1 for the 1998/99 and 1999/2000 seasons, respectively. Earlier sowing and successive delays in sowing from November caused substantial yield declines of as much as 72–75%. Sowing date influenced yields of bambara groundnut through the effect of temperature and daylength on plant development. For the landraces used in the study, while the rate of progress from sowing to flowering was influenced by temperature, the rate of progress from flowering to podding was influenced largely by daylength. The practical implications of the results for increased bambara groundnut production are discussed.

In the hilly areas of eastern Gujarat, western Madhya Pradesh and southern Rajasthan, in western India, farmers are very resource-poor and cultivate small and fragmented land holdings. Maize is their main rainy season (kharif) cereal and it is grown as a rainfed crop in low-fertility fields, often on sloping land that is vulnerable to soil erosion. Its productivity is very low, averaging below 1 t ha−1. New farm technologies to increase this productivity have to be low cost to be attractive to farmers who have limited access to purchased inputs and few means to purchase them. From observations of local farming practices, intercropping of maize with legumes was identified as an attractive option because the only additional input needed is seed of the legume crop. Participatory research was conducted on intercropping of maize with improved varieties of horsegram (Macrotyloma uniflorum). Many farmers who tried this intercropping adopted it in subsequent years, while others preferred to grow the new horsegram varieties as a sole crop. Farmers reported that less weeding was required in the intercrop as the horsegram smothered weeds. All farmers used the dry stover from the horsegram as a fodder for their animals. Farmers used the whole seed as dal, which provided additional protein in their diet. Farmers also sold the grain, but it fetched a low price in the poorly developed market for horsegram. Previously intercropping had been tried with local landraces, but the acceptance of intercropping was higher with new varieties such as AK-42 that yielded over 60% more grain. Participatory trials in which only one entry was compared with the local variety did not show a difference between AK-21 and AK-42 as in all cases both were preferred over the local variety. When they were directly compared with each other, farmers' perceptions showed a significant preference for AK-42. Variety IVH-2 was found to be better than AK-42: it matured 15 days earlier, better matching the maturity of the maize, had superior grain quality and yielded about the same. The greater uptake of improved horsegram varieties for sole and intercropping is likely to be limited by the lack of seed supply.

This paper explores how and to what extent women and men have benefited from social capital build-up (the ability of men and women farmers to develop and use various kinds of social networks and the resources that thereby become available) in technology uptake, and the role of women in this process. Using a series of three case studies on ICRISAT's Groundnut Production Technology, the process of technology uptake leading to empowerment is systematically documented through three stages of the adoption pathway. The process stimulating gender-equitable change and empowerment was examined through a sequential analysis using two in-depth case studies in three villages in Maharashtra, India, and complemented by a broader quantitative study of the uptake process covering villages in surrounding districts. This analysis illustrated that social capital is important for both adoption and impact to occur. Qualitative information complemented by quantitative measures provides a holistic understanding of the long-term effects and benefits. The findings illustrated that build-up of social capital improves access to resources like credit, information and knowledge about new technology options and practices. Furthermore, it expands choices available to each household member – e.g. selecting and adopting seed technology of their choice, and alternative investment options – and influences the distribution of benefits from the technology because of the ways in which social networks and social relationships facilitate technology dissemination. Mobilizing social capital through participation of men and women in groups/networks that crossed caste, class and gender barriers mediated the successful adoption and diffusion of technology.

Echinacea purpurea has been introduced in to Taiwan and grown successfully. However, information regarding the effects of the growing climate on its active constituents (e.g. caffeoyl derivatives) and biomass production is very limited. In this study the biomass of field-grown E. purpurea plants harvested during three different crop seasons was compared. The content of caffeoyl phenols and the production of aerial plant parts were also assayed. The results indicated that both morphological and agronomic traits were affected by crop season, with spring-grown plants producing more stems and flowers but fewer leaves than autumn-grown plants. Autumn-grown plants produced more caffeoyl phenols, particularly cichoric acid and caftaric acid, in leaf and flower tissues than spring grown plants. Thus, transplanting E. purpurea seedlings in the autumn and harvesting the aerial parts at the beginning of winter first, and then harvesting the rhizome-regenerated plants again in the following summer are technically feasible. This farming system would give commercial cultivation of E. purpurea in Taiwan a great competitive advantage over other growing regions, provided that an environmentally suitable population is selected and established in Taiwan.

Dormancy in seeds of Sesbania sesban is caused by a water-impermeable seed coat (hard seeds or hardseededness). A two-phase pretreatment technique was developed for breaking seed dormancy and was validated using different accessions and seed lots. Seeds were first soaked in water at 80 °C for 8 min and prepared for the germination test. Ungerminated hard seeds at the first count (after four days incubation) during the germination test were then subjected to a second treatment by mechanically scarifying the seed coat. The effects of water temperature and variation in initial hardseededness and viability among and within accessions were also investigated. The optimum water temperature, allowing maximum seed germination without increasing the percentage of abnormal seedling/dead seeds was 80 °C. The mean percentage of hard seeds across 30 seed lots of six accessions was reduced to 26% after phase 1 and to 0% after phase 2. In addition, full germination occurred within only 10 days for treated seeds while germination in untreated seeds had reached only 48% after 14 days. Significant differences existed among the seed lots within the accessions (p > 0.05) for the percentage of initial hard seed and for the effects of treatments on breaking seed dormancy. The two-phase technique developed was validated using over 1000 seed lots of S. sesban, and it was found to be a rapid and cost-effective method for breaking hard seed dormancy with potential for wider use for hard-seeded legumes.