RESUMO
The historical meeting between originally American people, European colonizers, and slaved peoples from Africa in the biome Pampa in South Brazil and Uruguay involved a cultural syncretism and a great genetic diversity of landraces of cultivated species. Genetic richness evolved by selection and cultural processes in response to different environments, cultural backgrounds, and needs. This review summarized the knowledge on vegetable and maize landraces in South Brazilian and Uruguayan Pampa biome, to design a strategy towards the rediscovery, conservation, and sustainable use. Landraces diversity maintained in situ and ex situ is described, specific case studies are presented, and the main problems and tools towards landraces re-valorization are discussed. We show that traditional family farming systems maintain diverse vegetable species, mainly squashes (Cucurbita spp.), sweet potato (Ipomoea batatas), beans (Phaseolus spp.), onion (Allium cepa), peppers (Capsicum spp.), tomato (Solanum lycopersicum), next to leafy vegetables and maize, among others. We propose the priority of systematic surveys as a basis for monitoring genetic erosion, increasing complementariness between in situ and ex situ conservation, and implementing sustainable conservation and utilization. The case studies highlight genetic diversity within each cultivated species, with different crop physiological responses; disease resistances, different quality traits and associated uses, from animal feeding in maize to a range of culinary uses linked to traditional culture in maize and vegetable species, and ornamental uses of specific Capsicum and Cucurbita. Some landraces were the basis for breeding, where improved cultivars allowed the competitiveness of landrace germplasm in the markets. Renewed industrialized products allowed the competitive and sustainable use of Capsicum landraces in Brazilian farmers communities. Strategies towards in situ conservation improvements and valorization are discussed; emphasizing the role played by agroecology, community seed banks and custodian farmers, participatory plant breeding, promotion of landraces specialties among consumers, and the need of research and capacity building, among others. Farmers' participation in the decisions is a key factor, along with the academia and the public sector. Landraces and associated knowledge are treasures to be used to benefit from farmers to consumers, directing the course of agriculture towards sustainable directions.
RESUMO
Abstract The objective of this work was to evaluate the genetic variability for the synthesis of bioactive compounds and minerals in pumpkin (Cucurbita moschata) landraces. Total phenolic compounds, carotenoids, antioxidant activity and minerals were evaluated in 10 accessions of Cucurbita moschata landraces from the Genebank of Embrapa Temperate Agriculture (Pelotas - RS, Brazil). Twenty plants of each accession were cultivated in the field during the spring/summer of 2013/2014. After harvesting of mature fruits, the seeds were discarded and opposite longitudinal portions of the pulp were manually prepared for analysis of the bioactive compounds. For the determination of minerals, pumpkin samples were frozen in plastic bags, and after freeze-dried and milled. All analysis were performed in triplicate. The data obtained showed high genetic variability for the synthesis of phenolic compounds, carotenoids, antioxidant activity and minerals. The accessions C52, C81, C267 e C389 showed high levels of antioxidants and minerals, being recommended for use in pumpkin breeding programs. The accessions C52 and C389 are promising, especially because they present the highest levels of total carotenoids.
