Improving Activity of Native Arbuscular Mycorrhizal Fungi (AMF) for Mycorrhizal Benefits in Agriculture: Status and Prospect

Abstract

Crop adaptation plays a key role in enabling farmers to adapt to the impacts of climate change. According to the latest report from the Intergovernmental Panel on Climate Change (IPCC), cultivar adjustment is the single most effective on-farm adaptation strategy, but the report is largely silent on the modalities of cultivar adjustment; what are the assumptions with regard to the cultivar types used and the institutional context in which the adjustments will take place? The objective of the current paper is to explore these modalities and enhance our understanding of the potential for crop adaptation in Sub Saharan Africas's agriculture. We identify the key environmental impacts and the adaptation options vis-à-vis these impacts. Drawing on insights and perspectives from the international scholarly literature on genetic resources and seed systems, we report on a local case study from the semi-arid zone in Tanzania. Farmers use a range of varieties and seed systems to cope with current climatic stress and our findings from Tanzania illustrates that crop adaptation is not only a question of switching from one modern variety to another as commonly assumed in the Climate Change impact and ada-ptation literature. In our case study, only 24 % of the maize seeds and 8 % of the sorghum seeds were sourced through seed supply channels classified as formal. However, in the case of maize, we found that at least 11 % of the seeds sourced from informal seed supply channels were farm-saved modern varieties. Open Pollinated Varieties of maize developed in public breeding programs in collabo-ration with international programs in the 1980s are still an important part of farmers' adaptive capacity. Our results further indicate that crop adaption can happen through creolization between modern and local varieties in the local seed R. Lal et al. (eds.), Climate Change and Multi-Dimensional Sustainability in African Agriculture, DOI 10.1007/978-3-319-41238-2_18 327 system. We argue that seed security in the face of climatic change depends on adaptive seed systems, which integrate formal and informal seed system approaches to the development, release and distribution of varieties. The negative impacts of anthropogenic climate change are already evident in food production in Sub-Saharan Africa (SSA) and will most likely grow stronger over the course of the next decades. According to the majority of the climate change models, our crops will face a gradual increase in mean temperatures and changes in rainfall patterns, as well as increased frequencies of extreme weather events. Today's extremes are set to become tomorrow's normal and many areas will experience conditions outside the historical ranges of the Holocene climate—the geological period in which our crops have evolved and thus become adapted. There are basically four ways in which plant populations can react to changes in growing conditions: adaptation, plasticity, migration or extinction. Which of the four out-comes we get depends on our management of the available genetic diversity. Crops are domesticated and their future is, by definition, in our hands. This chapter is about the basic components of successful crop adaptation: genetic resources, which are the raw material for adaptation, and the seed systems, which are the institutions farmers and breeders rely on when they deploy these resources to adapt to novel climates. The chapter proceeds as follows: first, we provide a review of the impact projections for SSA and single out the key environmental factors to which our crops will have to adapt. Secondly, we review the adaptation concept in the climate change literature and explore what the literature on genetic resources and seed systems can contribute to broaden the perspective on crop adaptation. Thirdly, we present a local case study of the role of genetic resources and seed systems for adaptation from Tanzania, drawing on the expanded toolbox for crop adaptation studies introduced in the preceding section. In the final section, we discuss some key features that we believe are needed to create adaptive seed systems. 18.2 Impact Projections and the Factors of Change