Sweet potato (Ipomoea batatas L.) is a versatile crop, but it is often grown in marginal and low-fertility areas, which reflects storage root yields far below its potential. For this reason, balanced liming and fertilization in sweet potato are essential to increase crop yield. Based on this approach, themes related to the nutritional requirements of sweet potato are presented and discussed considering the main cultivars currently used in Brazil as well as references for rational fertilization management in this crop. Sweet potato is a crop that absorbs large amounts of nutrients during its development cycle, but this should not be used as a prerogative to excessively increase the fertilizer rates applied in this root crop. As a strategy for rational fertilization management, one should take advantage of the ability of this crop to associate with N-fixing microorganisms, thus reducing the use of mineral N. Moreover, it is necessary to encourage the use of organic fertilizer, whether using animal manure or green manure. In addition to increasing storage root yield and improving storage root shape, organic fertilizers can partially replace mineral chemical fertilizers. Studies aimed at updating cultivar-specific potassium and phosphate fertilizer recommendations should also be encouraged, as well as research addressing micronutrient supply for sweet potato.

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Sweet potato crops take up large amounts of nutrients, especially nitrogen. In low-fertility soils, the addition of nitrogen (N) increases the sweet potato yield. Green manure may be an alternative method for improving soil quality and supplying nutrients to this crop. This study aimed to evaluate the plant's nutritional status and the amount of nutrients taken up and removed by sweet potato plants subjected to green manure and mineral N fertilization. The experiment was carried out in the field for two growing seasons using a randomized block design in a split-plot scheme with four replications. The plots consisted of a control treatment (spontaneous weeds) and the previous cultivation of Crotalaria spectabilis and Mucuna aterrima. The subplots consisted of four N rates (0, 50, 100, and 200 kg ha -1 ) that were applied to the sweet potato. The species M. aterrima is more suitable for use as green manure in the sweet potato than C. spectabilis. Nitrogen application rates promoted a greater increase in the biomass of the storage root, nutrient uptake, and removal in the sweet potatoes unfertilized with green manure. In the sweet potato fertilized with M. aterrima, mineral N supply in excess (above 50 kg ha -1 ) increases the nutrient uptake and removal without a significant increase in the biomass of the storage root. In the sweet potatoes unfertilized with green manure, high rates of N (greater than 120 kg ha -1 ) must be applied to obtain the utmost biomass of the storage root, nutrient uptake and removal.

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A exploração intensa e seletiva de madeira, mudanças no uso da terra pelo agronegócio e ocupação urbana são os principais fatores responsáveis pela perda na diversidade de espécies arbóreas. Junto com o agravamento do processo de degradação ambiental e esgotamento dos recursos naturais disponíveis no planeta, nota-se um substancial crescimento da preocupação com os danos ambientais causados na reprodução e diversidade genética das espécies arbóreas. Com essa constatação, tornou-se fundamental conservar a variabilidade das espécies utilizando-se bancos de germoplasmas. Nesse contexto, a presente revisão objetivou reunir informações sobre a biodiversidade e o ambiente para a conservação de espécies arbóreas nativas. Demonstra-se que especialmente aqueles métodos em que se utilizam os bancos de germoplasmas in situ ou ex situ contribuem e garantem a preservação das espécies, mantendo ampla diversidade e variabilidade genética das populações arbóreas.