Awareness of the need for biodiversity conservation is now universally accepted, but most often recent conservation activities have focused on wild species. Crop species and the diversity between and within them has significant socioeconomic as well as heritage value. The bulk of genetic diversity in domesticated species is located in traditional varieties maintained by traditional farming systems. These traditional varieties, commonly referred to as landraces, are severely threatened by genetic extinction primarily due to their replacement by modern genetically uniform varieties. The conservation of landrace diversity has been hindered in part by the lack of an accepted definition to define the entity universally recognized as landraces. Without a definition it would be impossible to prepare an inventory and without an inventory changes in landrace constituency could not be recognized over time. Therefore, based on a literature review, workshop discussion and interviews with key informants, common characteristics of landraces were identified, such as: historical origin, high genetic diversity, local genetic adaptation, recognizable identity, lack of formal genetic improvement, and whether associated with traditional farming systems. However, although these characteristics are commonly present they are not always all present for any individual landrace; several crop-specific exceptions were noted relating to crop propagation method (sexual or asexual), breeding system (self-fertilized or cross-fertilized species), length of formal crop improvement, seed management (selection or random propagation) and use. This paper discusses the characteristics that generally constitute a landrace, reviews the exceptions to these characteristics and provides a working definition of a landrace. The working definition proposed is as follows: ‘a landrace is a dynamic population(s) of a cultivated plant that has historical origin, distinct identity and lacks formal crop improvement, as well as often being genetically diverse, locally adapted and associated with traditional farming systems’.

Mixed crop–livestock farming systems prevail in Mexico – typically rain-fed and smallholder systems based on maize and ruminants and spanning diverse agro-ecologies. Maize grain is the key Mexican staple produced for home consumption and the market. Maize crop residues (stover) are an important by-product, primarily for feed use, often through in situ stubble grazing and/or as ex situ forage. This paper explores maize stover use along the agro-ecological gradient and the potential trade-offs, particularly the widespread use of maize stover as feed against its potential use as mulch (soil cover) to manage soil health within the context of conservation agriculture. The paper builds on three case study areas in Mexico in contrasting agro-ecologies: (semi-)arid, temperate highland and tropical sub-humid. Data were obtained through expert consultation and semi-structured farmer group/community surveys. Although in situ grazing is found in all three study sites, it represented the bulk of stover use in only one site (70% of stover in the sub-humid tropics), with ex situ feed dominating in the other two sites (>80%). Maize stover commercialization is limited and mainly restricted to households with no livestock and often within the local context. Farmers are generally hesitant to adopt conservation agricultural practices that require the retention of stover as mulch, as this competes with their livestock feed needs and purchased feed is expensive. To reduce trade-offs, a portfolio of options could be adapted to these mixed systems, including partial residue retention, cover and feed crops and sustainable intensification. Promising but yet to be explored, are investments in the genetic improvement of maize stover feed quality

Purpose of Review: The paper discusses how robotics and autonomous systems (RAS) are being deployed to decarbonise agricultural production. The climate emergency cannot be ameliorated without dramatic reductions in greenhouse gas emissions across the agri-food sector. This review outlines the transformational role for robotics in the agri-food system and considers where research and focus might be prioritised. Recent Findings: Agri-robotic systems provide multiple emerging opportunities that facilitate the transition towards net zero agriculture. Five focus themes were identified where robotics could impact sustainable food production systems to (1) increase nitrogen use efficiency, (2) accelerate plant breeding, (3) deliver regenerative agriculture, (4) electrify robotic vehicles, (5) reduce food waste. Summary: RAS technologies create opportunities to (i) optimise the use of inputs such as fertiliser, seeds, and fuel/energy; (ii) reduce the environmental impact on soil and other natural resources; (iii) improve the efficiency and precision of agricultural processes and equipment; (iv) enhance farmers’ decisions to improve crop care and reduce farm waste. Further and scaled research and technology development are needed to exploit these opportunities.

Understanding the causes of maize landrace loss in farmers’ field is essential to design effective conservation strategies. These strategies are necessary to ensure that genetic resources are available in the future. Previous studies have shown that this loss is caused by multiple factors. In this longitudinal study, we used a collection of 93 maize landrace accessions from Morelos, Mexico, and stored at the International Maize and Wheat Improvement Center (CIMMYT) Maize Germplasm Bank, to trace back to the original 66 donor families after 50 years and explore the causes for why they abandoned or conserved their seed lots. We used an actor-centered approach, based on interviews and focus group discussions. We adopt a Multi-Level Perspective framework to examine loss as a process, accommodating multiple causes and the interactions among them. We found that the importance of maize landrace cultivation had diminished over the last 50 years in the study area. By 2017, 13 families had conserved a total of 14 seed lots directly descended from the 1967 collection. Focus group participants identified 60 accessions that could still be found in the surrounding municipalities. Our findings showed that multiple interconnected changes in maize cultivation technologies, as well as in maize markets, other crop markets, agricultural and land policies, cultural preferences, urbanization and climate change, have created an unfavorable environment for the conservation of maize landraces. Many of these processes were location- and landrace-specific, and often led to landrace abandonment during the shift from one farmer generation to the next.

Despite international commitments to integrate indigenous peoples and their Traditional Ecological Knowledge (TEK) in actions combating climate change, their inclusion remains limited. Integrating TEK with scientific knowledge has become particularly important in sectors such as agriculture, which both contributes to and is affected by climate change. While there is a general recognition that integrating TEK will contribute to climate change adaptation, agricultural interventions have made little progress in achieving this due to the assumption of a clear divide between TEK and scientific knowledge. This paper considers that knowledge integration is already occurring, but in contexts of economic, sociocultural, and political inequalities. We elaborate on the case of traditional weather forecasting methods used by Mayan indigenous farmers in Mexico's Yucatán Peninsula to propose a social justice perspective for knowledge integration in climate change interventions. Using information from three studies conducted between 2016 and 2019, we first explain the importance of weather and traditional weather forecast methods for indigenous Mayan farmers. Later we describe in detail both these methods and their links with Mayan cosmology. Findings show how weather phenomena such as drought and hurricanes are main concerns for milpa farming. They illustrate the diversity of traditional short, medium, and long-term weather forecast methods based on observations from nature and the sky. Farmers also perform rituals that are related to their Mayan gods and goddess. As TEK not only defines agricultural calendars but also reproduces Mayan culture, we discuss what is needed for its integration into actions combating climate change. We use a rights-based approach that considers the economic, cultural, and political scales of justice to equally allocate resources and benefits for traditional knowledge systems, recognize indigenous values and worldviews avoiding cultural harms, and accomplish indigenous self-determination through equal representation. As a result, we hope to incentivize development actors engaged in agricultural interventions on climate change to critically reflect and examine power dynamics and relations when working with indigenous communities.