This doctoral thesis presents three original research papers investigating aspects of agricultural production in small-farming households in two regions of Ethiopia. While answering specific research questions, the articles are connected and motivated by an interest in essential themes of agricultural development: access to seed, the use and conservation of agrobiodiversity as well as strategies to manage production risk in smallholder agriculture. The first article analyses patterns of agrobiodiversity in three communities with comparatively favourable farming conditions and good market access in the East Shewa zone of Eastern Ethiopia. Using original panel data of more than 300 households collected in 2011 and 2013, the study shows that the least vulnerable households grow a larger portfolio of food crops and wheat varieties. Based on these findings, the role of agrobiodiversity for ex ante risk management and alternative incentives for portfolio diversification are discussed. The second article investigates the effects of a fungal crop disease on agricultural production of households in East Shewa using household level panel data during and after an epidemic outbreak of yellow rust in 2010/11. Findings suggest that while varietal diversity in wheat does not increase, roughly thirty percent of households make changes in their varietal portfolio and reduce wheat cultivation in response to the disease. Disease resistant varieties are only available to 16 percent of all households with preferential access to agricultural resources. The third article presents a mixed methods study of a highly developed informal seed insurance network among subsistence‐oriented small farmers in two communities in the West Hararghe zone of Ethiopia. Based on a survey and interviews with 150 farmers, we find that the vast majority of small farmers actively participate in informal seed assistance by giving or receiving small quantities of seed without compensation. We argue that the seed assistance through gifts is practiced to insure against hunger ex ante and facilitate access to crop genetic resources in a centre of crop origin and diversity.