Eggplant is the fifth most economically important solanaceous crop after potato, tomato, pepper and tobacco. Apart from the well-known brinjal eggplant (Solanum melongena L.), two other under-utilized eggplant species, the scarlet eggplant (S. aethiopicum L.) and the gboma eggplant (S. macrocarpon L.) are also cultivated. The taxonomy and identification of eggplant wild relatives is challenging for breeders due to the large number of related species, but recent phenotypic and genetic data and classification in primary, secondary and tertiary genepools, as well as information on the domestication process and wild progenitors, facilitates their utilization in breeding. The World Vegetable Center (WorldVeg) holds a large public germplasm collection of eggplant, which includes the three cultivated species and more than 30 eggplant wild relatives, with more than 3,200 accessions collected from 90 countries. Over the last 15 years, more than 10,000 seed samples from the Center’s eggplant collection have been shared with public and private sector entities, including other genebanks. An analysis of the global occurrences and genebank holdings of cultivated eggplants and their wild relatives reveals that the WorldVeg genebank holds the world’s largest public collection of the three cultivated eggplant species. The composition, seed dissemination and utilization of germplasm from the Center’s collection are highlighted. In recent years more than 1300 accessions of eggplant have been characterized for yield and fruit quality parameters. Further screening for biotic and abiotic stresses in eggplant wild relatives is a priority, as is the need to amass more comprehensive knowledge regarding wild relatives’ potential for use in breeding. However, as is the case for many other crops, wild relatives are highly under-represented in the global conservation system of eggplant genetic resources.

As part of conservation of plant genetic resources, long-term storage of seeds is highly relevant for genebanks. Here we present a systematic review and a meta-analysis of studies on seed longevity focusing on half-life (P50) under different storage conditions. Six studies were selected for the meta-analysis; in addition, a high number of additional references were included in the discussion of the results. The results show that under ambient conditions, half-life is short, from 5 to 10 years, while under more optimal conditions, which for orthodox seeds is at low humidity and low temperature, half-life is more in the 40−60 years range, although with large interspecies variation. Under long-term genebank conditions, with seeds dried to equilibrium and thereafter kept at minus 18−20°C in waterproof bags or jars, half-life can be twice or three times as long. In general, many of the grain legume seeds, as well as corn, common oat, and common barley are long-lived, while cereal rye, onion, garden lettuce, pepper, and some of the forage grasses are more short-lived. Conditions during maturation and harvesting influence longevity, and proper maturation and gentle handling are known to be of importance. Seed longevity models have been developed to predict final germination based on initial viability, temperature, humidity, storage time, and species information. We compared predicted germination to results from the long-term experiments. The predicted values were higher or much higher than the observed values, which demonstrate that something in the seed handling in the genebanks have not been optimal. Long-term studies are now available with data at least up to 60 years of storage. Our review shows that the knowledge and methodology developed for the conservation of plant genetic resources should also work for wild species of orthodox seed nature.

It is urgent that we increase global food production to support population growth. Food production requires significant resources, amongst them water and energy. Therefore, any losses of food or other agricultural products also means a waste of water and energy resources. A significant amount of these losses occurs during the postharvest stage, primarily during processing and storage. This is considered avoidable food waste. The water-energy-waste nexus (WEW), and its relationship to food production, needs to be investigated from a circular bioeconomy lens. Furthermore, alternative uses of the wastes should be investigated. This review focuses on agro-wastes and their management as sources for bioactive compounds, biofertilizers, biomaterials, nanomaterials, pharmaceuticals and medicinal agents, and growth media, e.g., for plant tissue culture. We also investigated the potential contribution of agro-wastes to bioenergy production (bioethanol, biogas, and biofuel). Proper management of agro-wastes may support the mitigation of climate change, produce innovative bio-ingredients and biodegradable materials, and enhance green growth and a circular bioeconomy. We argue that the management of agro-wastes cannot be discussed without referring to the role of water and energy within the food system. Thus, this review focuses on agricultural wastes and their handling, applications, environmental impacts, and potential benefits in the agricultural and medical industries in light of the WEW nexus.

Despite an increasing awareness of the potential of “orphan” or unimproved crops to contribute to food security and enhanced livelihoods for farmers, coordinated research agendas to facilitate production and use of orphan crops by local communities are generally lacking. We provide an overview of the current knowledge on leafy vegetables with a focus on Gynandropsis gynandra, a highly nutritious species used in Africa and Asia, and highlight general and species-specific guidelines for participatory, genomics-assisted breeding of orphan crops. Key steps in genome-enabled orphan leafy vegetables improvement are identified and discussed in the context of Gynandropsis gynandra breeding, including: (1) germplasm collection and management; (2) product target definition and refinement; (3) characterization of the genetic control of key traits; (4) design of the ‘process’ for cultivar development; (5) integration of genomic data to optimize that ‘process’; (6) multi-environmental participatory testing and end-user evaluation; and (7) crop value chain development. The review discusses each step in detail, with emphasis on improving leaf yield, phytonutrient content, organoleptic quality, resistance to biotic and abiotic stresses and post-harvest management.

The agricultural sector is a vital source of human well-being that provides the necessities of daily life. A variety of farming systems are utilized in agriculture, such as a wide range of tillage options, no-till, agroforestry, precision farming, organic farming, cover cropping, crop rotations, etc. Each of these farming systems has unique challenges, and nanotechnology has successfully improved on many of them. Agricultural applications of nanotechnology include nanofertilizers, nanopesticides, nanosensors, nanobiotechnology, and nanoremediation. This study focuses on the application of nano-farming technologies to different farming systems. Suggested practices include nano improvement of soil quality, crop nano-protection under biotic stress, nanoremediation of polluted soil and water environments, nanomanagement of agro-wastes, nano-agrochemicals, nano-precision farming, and nanobiotechnology for modern farming. This review also addresses expected problems that may occur due to over application of nanomaterials to farming systems, such as nanopollution and nanotoxicity of agroecosystem compartments. Several dimensions are emphasized in this study, such as green energy, sustainable development, the circular bioeconomy, land biodegradation, pollution, and the one health approach, as essential for the global goals of sustainable development. Nanofarming presents both benefits and obstacles to human life. The exact balance between these benefits and challenges needs more study.

This study provides insights in patterns of distribution of abiotic and biotic stress resilience across Vigna gene pools to enhance the use and conservation of these genetic resources for legume breeding. Vigna is a pantropical genus with more than 88 taxa including important crops such as V. radiata (mung bean) and V. unguiculata (cowpea). Our results show that sources of pest and disease resistance occur in at least 75 percent of the Vigna taxa, which were part of screening assessments, while sources of abiotic stress resilience occur in less than 30 percent of screened taxa. This difference in levels of resilience suggests that Vigna taxa co-evolve with pests and diseases while taxa are more conservative to adapt to climatic changes and salinization. Twenty-two Vigna taxa are poorly conserved in genebanks or not at all. This germplasm is not available for legume breeding and requires urgent germplasm collecting before these taxa extirpate on farm and in the wild. Vigna taxa, which tolerate heat and drought stress are rare compared with taxa, which escape these stresses because of short growing seasons or with taxa, which tolerate salinity. We recommend prioritizing these rare Vigna taxa for conservation and screening for combined abiotic and biotic stress resilience resulting from stacked or multifunctional traits. The high presence of salinity tolerance compared with drought stress tolerance, suggests that Vigna taxa are good at developing salt-tolerant traits. Vigna taxa are therefore of high value for legume production in areas that will suffer from salinization under global climate change.