Unlocking plant resources to support food security and promote sustainable agriculture

As the world's population is increasing, humanity is facing both shortages (hunger) and excesses (obesity) of calorie and nutrient intakes. Biodiversity is fundamental to addressing this double challenge, which involves a far better understanding of the global state of food resources. Current estimates suggest that there are at least 7,039 edible plant species, in a broad taxonomic sense, which includes 7,014 vascular plants. This is in striking contrast to the small handful of food crops that provide the majority of humanity's calorie and nutrient intake. Most of these 7,039 edible species have additional uses, the most common being medicines (70%), materials (59%), and environmental uses (40%). Species of major food crops display centers of diversity, as previously proposed, while the rest of edible plants follow latitudinal distribution patterns similarly to the total plant diversity, with higher species richness at lower latitudes. The International Union for Conservation of Nature Red List includes global conservation assessments for at least 30% of edible plants, with ca. 86% of them conserved ex situ. However, at least 11% of those species recorded are threatened. We highlight multipurpose NUS of plants from different regions of the world, which could be key for a more resilient, sustainable, biodiverse, and community participation-driven new “green revolution.” Furthermore, we explore how fungi could diversify and increase the nutritional value of our diets. NUS, along with the wealth of traditional knowledge about their uses and practices, offer a largely untapped resource to support food security and sustainable agriculture. However, for these natural resources to be unlocked, enhanced collaboration among stakeholders is vital

State of the world’s plants and fungi 2020

Kew’s State of the World’s Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kew’s State of the World’s Plants and Fungi sets an important international standard from which we can annually track trends in the global status of plant and fungal diversity

Outbreaks and new records. Cameroon : identification and characterization of pepper veinal mottle virus in Cameroon

International audienc

Urban agriculture in the developing world. A review.

The year 2007 marked a critical event in the world history. For the first time, more than half of the world population now lives in cities. In many developing countries, the urbanization process goes along with increasing urban poverty and polluted environment, growing food insecurity and malnutrition, especially for children, pregnant and lactating women; and increasing unemployment. Urban agriculture represents an opportunity for improving food supply, health conditions, local economy, social integration, and environmental sustainability altogether. Urban agriculture is present throughout the world in a diversity of farming systems. Urban dwellers ranging 25\u201330 % are involved worldwide in the agro-food sector. Urban agriculture will gain in recognition for its benefits and services because urban population and rural\u2013urban migration are increasing. The actual scarcity of knowledge on urban agriculture has somehow hindered the relevance of this activity. Here, we review the social, cultural, technical, economic, environmental, and political factors affecting urban agriculture with examples taken in East Asia, South America, or East Africa. We discuss the definition, benefits, and limitations of urban agriculture. Food security benefit of urban agriculture is evidenced by 100\u2013200 million urban farmers worldwide providing the city markets with fresh horticultural goods. Urban agriculture favors social improvement since the poors spend up to 85 % of their income in food purchase and most urban farmers belong to poorest populations. Sociologically urban farming favors both social inclusion and reduction of gender inequalities, as 65 % of urban farmers are women. Urban agriculture has ecological benefits by reducing the city waste, improving urban biodiversity and air quality, and overall reducing the environmental impact related to both food transport and storage. The production of horticultural goods shows the main benefits of urban agriculture. Fruit and vegetable crops give high yields, up to 50 kg m 122 year 121, a more efficient use of agricultural inputs, high added value, and rapidly perishable products that can easily substitute the rural production in the local market. Urban horticulture is the most competitive branch of urban farming due to the high cost of urban land and with the need of high water- and fertilizer-use efficiency. Traditional urban horticulture systems are classified in four types: allotment and family gardens, simplified extensive systems, shifting cultivation, and intensive systems. We describe also innovative systems including organoponics and simplified soilless cultures

Biological Constraints in Tomato Production in the Western Highlands of Cameroon

Tomato (Lycopersicon esculentum) production is handicapped by damage due to pests and pathogens. Farmers' fields in the western highlands of Cameroon were surveyed during 1993 to 1996 to identify biological constraints in production. Diseases and insect pests are the most important biological limitations in tomato production. Late blight caused by Phytophthora infestans and early blight caused by Alternaria solani are the most severe diseases, while the melon fruitfly (Dacus cucurbitae) is the most prevalent insect pest. Yield losses due to pest damage are high and reach 100 % when the crop is not treated in the wet season. Pest-resistant varieties are not available to farmers. Consequently, growers practise intensive pesticidal spray programmes to limit losses caused by pests and diseases. Results indicate the necessity for the adoption of integrated pest management strategies in tomato production in Cameroon

Optimisation de la technique de l'immunomarquage à l'or sur sections ultrafines réalisées à partir d’échantillons fixes à la glycéraldéhyde et au tétroxyde d'osmium et inclus dans une époxy-résine

National audienc

Migration des virus dans la plante. Revue bibliographique

Afin de générer une infection, un virus doit migrer dans sa plante hôte. Il existe 2 formes de migration des virus dans la plante : la migration à courte distance et la migration à longue distance. La migration à courte distance s'effectue de cellule à cellule. Au cours de ce processus, le virus migre des cellules infectées aux cellules adjacentes par les plasmodesmes. Plusieurs résultats indiquent que ce type de transport est sous le contrôle partiel du virus. En effet, chez différents phytovirus tels que le TMV, le TRV, le CPMV, l'AMV, le CaMV..., une ou plusieurs protéines, ayant une fonction de transport et dont les mécanismes d'action sont discutés, ont été caractérisées. La migration à longue distance qui s'effectue par les vaisseaux conducteurs est indispensable à l'établissement d'une infection systémique. Les mécanismes de la migration à longue distance restent l'objet de controverses car il n'est pas encore tout à fait établi si ce processus nécessite l'activité d'une fonction de transport ou si c'est un phénomène passif lié au transport des assimilats. Certains virus qui produisent normalement une infection subliminale ou qui restent localisés dans certains tissus se généralisent dans la plante lorsqu'ils sont co-inoculés avec d'autres qui sont eux systémiques. Apparemment, le virus assistant code pour une fonction qui manque au virus assisté dans cette plante, et cette fonction est probablement impliquée dans le transport. Cette revue présente une synthèse des différents aspects du transport des virus dans la plante de même que les mécanismes de la résistance des plantes à la migration des virus.The movement of viruses within the plant: a review. In order to generate a productive infection, a virus must move within its host plant. There are 2 forms of virus movement within a plant, namely, short distance and long distance. The short-distance movement is from cell to cell. During this process, the virus moves to an adjacent cell through the protoplasmic bridges, the plasmodesmata. Several results indicate that this form of spread is virus controlled. Indeed, proteins to which a movement function has been assigned have been identified in a number of plant viruses, such as TMV, TRV, CPMV, AMV and CaMV, to name a few. The long-distance movement takes place in the vascular tissues and it is a phenomenon essential in the establishment of a systemic infection. The mechanism of the long-distance spread is poorly understood. It is not yet clear whether movement in the vascular system requires the activity of a spread function or whether it is a passive process within the phloem elements. In certain combinations of viruses, one virus, which normally only establishes a subliminal or tissue-localized infection, invades other tissues along with the other virus. The "helper" virus apparently provides a function, presumably involved in spread, that the "helped" virus lacks in that plant. This review has sought to deal with the different aspects of virus spread within a plant and also with the mechanisms of plant resistance to virus movement

Application des methodes DAS et PAS ELISA pour la detection de differents virus infectant le piment

* INRA, Station de Pathologie Vegetale, Montfavet (FRA) Diffusion du document : INRA, Station de Pathologie Vegetale, Montfavet (FRA)National audienc