Resumo Hymenaea stigonocarpa é uma espécie arbórea medicinal usada na recuperação de áreas degradadas. No entanto, pouco se sabe sobre suas exigências nutricionais durante a fase de mudas, principalmente em termos de potássio. Dessa forma, objetivou-se com este trabalho avaliar se doses potássicas promovem alterações morfofisiológicas de mudas Hymenaea stigonocarpa. O delineamento utilizado foi inteiramente ao acaso, com seis doses (0, 50, 100, 150, 200 e 250mg dm-3 de KCl), e quatro repetições. As variáveis avaliadas foram: biométricas, biomassa, fisiológicas e teor de potássio. A espécie apresentou resposta significativa à adubação potássica para os parâmetros fisiológicos e biométricos. Os maiores valores obtidos foram nas doses entre 150 e 200 mg dm-3. E, ainda, observou-se efeito de concentração para o teor de potássio contido nas folhas e caule das mudas de Hymenaea stigonocarpa.

Abstract Hymenaea stigonocarpa is anarboreal medicinal species used in the recovery of degraded areas. However, little is known about its nutritional requirements during the seedling phase, especially concerning to potassium. In this context, the aim of this study was to evaluate if potassium doses promote morphophysiological changes in Hymenaea stigonocarpa seedlings.A completely randomized design, consisting in six KCl doses (0, 50, 100, 150, 200 and 250 mg dm-3 KCl) and four replications was applied. Biometric, biomass, physiological and potassium content variables were assessed. Hymenaea stigonocarpa displayed significant physiological and biometric responses to potassium fertilization, with the highest values observed at doses ranging from 150 to 200 mg dm-3 KCl. Moreover, concentration effects were noted regarding to potassium contents in seedling leaves and stems.

Resumo O objetivo deste estudo foi determinar de que forma as mudas de Guazuma ulmifolia respondem a doses nitrogenadas, tendo como fonte de nitrogênio (N) a ureia. O cultivo das mudas ocorreu em delineamento inteiramente ao acaso, as quais foram submetidas a cinco doses (0, 50, 100, 150 e 200 mg dm-3) de N. Aos 120 dias de cultivo foram realizadas avaliações biométricas, fisiológicas, acúmulo de biomassa, razões alométricas, índice de qualidade de Dickson (IQD), teor, acúmulo e eficiência do uso de N (EUN) na parte aérea das mudas. Os dados foram submetidos a análise de variância e regressão. Além disso, o coeficiente de correlação de Pearson também foi analisado. As doses de N promoveram significativamente (p≤0,05) o aumento do teor de N na parte aérea das mudas. Por outro lado, registrou-se a redução significativa do acúmulo de N, de variáveis fisiológicas, crescimento, biomassa, IQD e EUN, que culminou em correlação negativa com o fornecimento crescente de N. Doses de N muito elevadas, tendo como fonte a ureia, foram prejudiciais para as mudas de Guazuma ulmifolia. As doses entre 20 e 38,8 mg dm-3 de N, de modo geral, foram as que promoveram os melhores resultados.

Abstract The aim of this study was to determine how Guazuma ulmifolia seedlings respond to nitrogen doses, with urea as a nitrogen source (N). The seedlings were cultivated in a completely randomized design, which were subjected to five doses (0, 50, 100, 150 and 200 mg dm-3) of N. At 120 days of cultivation, biometric, physiological, biomass accumulation, allometric ratios, Dickson's quality index (IQD), content, accumulation and N efficiency use (NUE) in the aerial part of the seedlings. The data were submitted to analysis of variance and regression. In addition, Pearson's correlation coefficient was also analyzed. The N doses significantly promoted (p≤0.05) the increase in the N content in the aerial part of the seedlings. On the other hand, there was a significant reduction in the N accumulation, of physiological variables, growth, biomass, IQD and NUE, which resulted in a negative correlation with the increasing N supply. Very high N doses, having as source the urea, were harmful to the seedlings of Guazuma ulmifolia. The doses between 20 and 38.8 mg dm-3 of N, in general, were those that promoted the best results.

Abstract In face of the global situation, a practice which has been gaining strength is producing seedlings for environmental restoration. Among the species that stand out for such activity is Hymenaea stigonocarpa. However, little is known about their nutritional requirements. The objective of this study was to evaluate the morphophysiological behavior of H. stigonocarpa seedlings submitted to phosphorus doses. The design was completely randomized with five doses (0, 100, 200, 300 and 400 mg dm-3) and four replicates. Physiological, morphological, biomass and phosphorus content analyses were performed. There was a difference for root mass ratio, leaf mass ratio, shoot mass ratio, leaf area and root area. The dose of 200 mg dm-³ is recommended for H. stigonocarpa seedlings.

Abstract Annona crassiflora is a medicinal species and source of food with little information about its nutritional requirements during the initial phase. Therefore, the objective of this study was to evaluate liming, phosphate fertilization and its interaction in A. crassiflora seedlings. The experiment was in a 4 × 4 factorial scheme with four replications in a randomized block design. The base saturations were: 8.3%, 25%, 50% and 75% and phosphorus: 0 mg dm-3, 100 mg dm-3, 200 mg dm-3 and 400 mg dm-3. The variables evaluated were biometrics, biomass and nutritional analysis. The species responded to the factors in isolation, and the increase in base saturation levels and phosphorus doses promoted significant effects for biometric variables, biomass, calcium, magnesium, nitrogen, phosphorus and potassium content. The saturation level promoted the best results, being 75% base saturation, while the highest phosphorus dosage was 400 mg dm-3.

RESUMO A calagem é benéfica para as plantas por promover a elevação do pH, neutralização do alumínio tóxico, aumentar o fornecimento de cálcio (Ca²+) e magnésio (Mg²+) e propiciar maior sistema radicular. No entanto, sabe-se que as espécies, principalmente nativas do Cerrado, respondem de formas distintas a essa técnica. Diante do exposto, o objetivo deste estudo foi determinar de que forma mudas de Hymenaea stigonocarpa (“Jatobá-do-Cerrado”) respondem a calagem em Latossolo Vermelho Distrófico. As plantas foram cultivadas em vasos de quatro litros, submetidas a diferentes saturações de bases (solo natural, 30, 45, 60 e 75% de V) e mantidas em casa de vegetação. Foram avaliadas a biometria, biomassa, teor nutricional e parâmetros fisiológicos. Houve diferença para o teor de Ca²+ e Mg²+ nas folhas e caule e isso culminou na redução significativa da condutância estomática, transpiração, concentração interna de CO2 e a relação concentração interna e externa de CO2, o que levou a redução do investimento em crescimento e biomassa. Diante dos resultados obtidos, para a produção de mudas de H. stigonocarpa em Latossolo Vermelho Distrófico não há necessidade de realizar calagem.

ABSTRACT Liming is beneficial for plants as it promotes pH elevation, neutralization of toxic aluminum, increase in calcium (Ca²+) and magnesium (Mg²+) supply, and provides greater root systems. However, it is known that different species, mainly those native to the Cerrado, respond in different ways to this technique. Given the above, the objective of this study was to determine how Hymenaea stigonocarpa (“Jatobá-do-Cerrado”) seedlings respond to liming in Dystrophic Red Latosol. The plants were cultivated in four-liter pots, submitted to different base saturation (natural soil, 30, 45, 60 and 75% V) and maintained in a greenhouse. Biometrics, biomass, nutritional content and physiological parameters were evaluated. A difference in Ca²+ and Mg²+ contents between leaves and stems was observed, leading to significant reductions in stomatal conductance, transpiration, internal CO2 concentration and internal and external CO2 concentration ratios, resulting in a reduction of the investment in growth and biomass. Given these results, there is no need for liming in the production of H. stigonocarpa seedlings in a Dystrophic Red Latosol.

ABSTRACT Annona crassiflora Mart. presents medicinal and food potential, and is also used in the recovery of degraded areas, however, little is known about its nutritional requirements. The aim of this work was to analyze the initial growth of A. crassiflora submitted to nitrogen and potassium fertilization. The experiment was conducted with a complete randomized block design with four replicates, each consisting of five nitrogen and potassium doses (0, 50, 100, 150 and 200 mg dm-3). Results were submitted to regression analysis. The species showed significant response for nitrogen fertilization regarding biometric variables, biomass, DQI and nutritional contents at doses of 100 to 200 mg dm-3. On the other hand, potassium only influenced DQI, nutritional content and accumulation of A. crassiflora seedlings.