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Local seed systems remain the fundamental source of seeds for many crops in developing countries. Climate resilience for small holder farmers continues to depend largely on locally available seeds of traditional crop varieties. High rainfall events can have as significant an impact on crop production as increased temperatures and drought. This article analyzes the dynamics of maize diversity over 3 years in a farming community of Yucatán state, Mexico, where elevated levels of precipitation forced farmers in 2012 to reduce maize diversity in their plots. We study how farmers maintained their agroecosystem resilience through seed networks, examining the drivers influencing maize diversity and seed provisioning in the year preceding and following the 2012 climatic disturbance (2011–2013). We found that, under these challenging circumstances, farmers focused their efforts on their most reliable landraces, disregarding hybrids. We show that farmers were able to recover and restore the diversity usually cultivated in the community in the year following the critical climate event. The maize dynamic assessed in this study demonstrates the importance of community level conservation of crop diversity. Understanding farmer management strategies of agrobiodiversity, especially during a challenging climatic period, is necessary to promote a more tailored response to climate change in traditional farming systems.

The present study was intendant to evaluate variations among flaxseed varities in terms of fatty acid composition, phytochemical profiles, and antioxidant activities determined by oxygen radical absorbance capacity (ORAC), 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ferrous ion reducing antioxidant power (FRAP) assays. Significant variations in the fatty acid composition, phenolic acids and lignan were observed in flaxseed varieties from different countries. Among these flaxseed verities, the unsaturated fatty acids accounted over four fifths of total fatty acid contents. The highest ratio of linolenic acid of total fatty acid was observed in USPEA, whereas the lowest one was found in Yexiao. USPEA showed the most contents of total phenolics, as well as flaxseed lignans. In general, total phenolics appeared to be the main contributors in the antioxidant capacity of flaxseed, which presented significant positive correlation. Our study revealed that both cultivar and origin of seeds significantly affect fatty acid composition, phenolic acids, lignans and subsequent antioxidant activities in flaxseed. The results provide new aspects of breeding resources of flaxseed cultivars by presenting their quality specification and possible commercial value.

Conservation biologists should seek to work with those involved in sustainable agriculture and rural development in expanded integrated approaches to reduce pesticide harm to humans, biodiversity and environmental services. Despite new evidence, conservation organisations have tended not to fully recognize the impacts of pesticides on biodiversity, and current conservation strategies pay little heed to addressing this threat. A comprehensive suite of strategies are required to reduce and rationalize pesticide use and mitigate risks to species conservation. This paper proposes six steps for conservationists to address pesticide problems: (1) revisit the land sparing versus land sharing debate and include the external impacts of agriculture as vital components in systematic conservation planning; (2) redefine narratives on intensive agriculture and support emerging forms of sustainable intensification; (3) focus and inform on improved delivery mechanisms and monitoring legal use to achieve better pesticide targeting and a major reduction in volumes used; (4) support efforts to reduce wastage and inefficiency in the food system by promoting technical changes and informed consumer choice; (5) design and encourage resilient temperate and tropical landscapes that minimise pesticide contamination on farms and at landscape scale; and (6) develop comprehensive policy responses to promote both better alternatives to synthetic pesticides and limit the use of the most harmful pesticides.

Angular leaf spot (ALS) is one of the most economically important bean diseases in Africa. One promising control option for the disease is the use of mixtures of resistant and susceptible varieties. This research evaluated (1) the reaction of farmer preferred bean varieties to ALS in the screenhouse and on-station and (2) the effect of different spatial arrangements of resistant and susceptible bean varieties on ALS disease development. For the latter, five mixture combinations and two controls were laid out in a Randomized Complete Block Design having three replicates. Analysis of variance and least significant differences (LSDs) were used to compare disease levels in both studies above. Varietal screening showed significant differences in varietal reaction to ALS. Screenhouse disease scores ranged between 0 and 5, compared to 0.7–3.9 in the field. For the varietal mixture trial, the lowest disease levels and the highest mixture efficiencies were observed for the combination of equal proportions ...

In this chapter, we develop new indicators and statistical tests to characterize patterns of crop diversity at local scales to better understand interactions between ecological and socio-cultural functions of agroecosystems. Farms, where a large number of crops (species or landraces) is grown, are known to contribute a large part of the locally available diversity of both rare and common crops but the role of farms with low diversity remains little understood: do they grow only common varieties—following a nestedness pattern typical of mutualistic networks in ecology—or do ‘crop–poor’ farmers also grow rare varieties? This question is pivotal in ongoing efforts to assess the local-scale contribution of small farms to global agrobiodiversity. We develop new network-based approaches to characterize the distribution of local crop diversity (species and infra-species) at the village level and to validate these approaches using meta-datasets from 10 countries. Our results highlight the sources of heterogeneity in crop diversity at the village level. We often identify two or more groups of farms based on their different levels of diversity. In some datasets, ‘crop–poor’ farms significantly contribute to the local crop diversity. Generally, we find that the distribution of crop diversity is more heterogeneous at the species than at the infra-species level. This analysis reveals the absence of a general pattern of crop diversity distribution, suggesting strong dependence on local agro-ecological and socio-cultural contexts. These different patterns of crop diversity distribution reflect an heterogeneity in farmers’ self-organized action in cultivating and maintaining local crop diversity, which ensures the adaptability of agroecosystems to global change.

As growth in population, gross domestic product (GDP) and consumption continues, further demands are placed on land, water and other resources. The resulting degradation can threaten the food security of poor people in fragile environments, particularly those whose livelihoods rely largely on agricultural activities. The concept of diversified or multifunctional agroecosystems is a relatively recent response to the decline in the quality of the natural resource base. Today, the question of agricultural production has evolved from a purely technical issue to a more complex one characterized by social, cultural, political and economic dimensions. Multifunctional agroecosystems carry out a variety of ecosystem services, such as the regulation of soil and water quality, carbon sequestration, support for biodiversity and sociocultural services, as well as meeting consumers' needs for food. In turn, these systems also rely on ecosystem services provided by adjacent natural ecosystems, including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling and hydrological services. However, poor management practices in agroecosystems can also be the source of numerous disservices, including loss of wildlife habitat, nutrient runoff, sedimentation of waterways, greenhouse gas emissions, and pesticide poisoning of humans and non-target species. This chapter discusses the challenges to agroecosystem management, and how adopting a diversified approach will enable farmers to farm longer and more sustainably in an environment of greater uncertainty, in the face of climate change.

Agriculture and ecosystem services are interrelated in various ways. Payments for ecological services (PES) and innovative methods of agricultural management, including ecological agriculture, conservation agriculture and the management of biological diversity are options for enhancing ecosystem services in agroecosystems while sustaining or increasing productivity. Successful actions will depend on strong supporting policies and legal frameworks, as well as on developing the knowledge and leadership capacity in farming communities to evaluate the potential benefi ts. The maintenance of ecosystem services and the long-term productivity and stability of agriculture ecosystems requires a paradigm shift in agriculture that moves away from single solutions to production problems towards a portfolio approach that supports multiple ways to better use soil, water and biotic resources to enhance ecosystem services.