This paper takes the viewpoint of a social scientist and looks at agricultural scientists' pathways for science impact. Awareness of these pathways is increasingly becoming part and parcel of the professionalism of the agricultural scientist, now that the pressure is on to mobilize smallholders and their productive resources for (global) food security and for reducing persistent rural poverty. Significant new thinking about pathways is emerging and it is useful to present some of this, even if it is not cut-and-dried.

Most cocoa farmers in Ghana do not adopt research recommendations because they cannot afford the cost, therefore, yields are low. Integrated pest management (IPM) technologies that rely on low external inputs were tried with a group of farmers. The technologies included using aqueous neem seed extracts to control capsids; removing diseased pods to reduce blackpod incidence; controlling mistletoes, epiphytes, weeds; and managing shade. Although yields increased significantly, adoption was constrained by technical, social and economic factors.

Little is known about effective ways to operationalize agricultural innovation processes. The authors of this article use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how innovation processes occur in heterogeneous and changing contexts. Their research shows how a program, that initially had a relatively narrow technology focus, evolved towards an innovation system approach.

Poor farmers seldom benefit from new agricultural technologies. In response, research and extension approaches based on agricultural innovation systems are popular. Often agricultural research organisations are the network brokers, facilitating the emergence of the innovation system. Based on an analysis of the Sustainable Modernization of Traditional Agriculture (MasAgro) initiative in Mexico, this viewpoint suggests that such organisations are more often suitable network brokers when the objective is the development and scaling out of a technology by itself.

Many small-scale irrigation systems are characterized by low yields and deteriorating infrastructure. Interventions often erroneously focus on increasing yields and rehabilitating infrastructure. Small-scale irrigation systems have many of the characteristics of complex socio-ecological systems, with many different actors and numerous interconnected subsystems. However, the limited interaction between the different subsystems and their agents prevents learning and the emergence of more beneficial outcomes.

This paper (Part I) present a case study of work conducted by the International Centre for Tropical Agriculture (CIAT) to adapt network mapping techniques to a rural and developing country context. It reports on work in Colombia to develop a prototype network diagnosis tool for use by service providers who work to strengthen small rural groups. It is complemented by a further paper in this issue by Louise Clark (Part II) which presents work to develop a network diagnosis tool for stakeholders involved in agricultural supply chains in Bolivia.

Innovations generally arise out of a network of actors and relationships and network structure determines how effective networks are at fostering innovation. This paper (Part II) presents work to develop a network diagnosis tool for stakeholders involved in agricultural supply chains in Bolivia. The prototype method used is based on social network analysis methodology. This paper concludes with a final section to identify lessons learnt and makes recommendations for future research.

Sustainable agricultural intensification requires the use of multiple agricultural technologies in an integrated manner to enhance productivity while conserving the natural resource base. This study analyses the adoption and impacts of sustainable intensification practices (SIPs) using a dataset from Ghana. A multivariate probit (MVP) model was estimated to assess the adoption of multiple SIPs. Moreover, we used a multivalued semi-parametric treatment effect (MVTE) model to estimate the effects of adopting multiple SIPs on maize productivity.

This article addresses the impact of Integrated Agricultural Research for Development (IAR4D) on food security among smallholder farmers in three countries of southern Africa (Zimbabwe, Mozambique and Malawi). Southern Africa has suffered continued hunger despite a myriad of technological interventions that have been introduced in agriculture to address issues of food security, as well as poverty alleviation.

Climate variability and change threaten and impact negatively on biodiversity, agricultural sustainability, ecosystems, and economic and social structures – factors that are all vital for human resilience and wellbeing. To cope with these challenges, embracing sustainability in food production is therefore essential. Practising sustainable agriculture is one way of ensuring sustainability in pro-poor farming communities in low-income countries.