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The objective was to evaluate the effect of the glyphosate on Hymenaea courbaril L. A randomized block design with five replications was implemented. Each experimental unit was composed of one plant in a 5 L container. The treatments were 0 "control"; 96; 240; 480; and 960 g ha-1 "corresponding to 10, 25, 50, and 100% of the commercial dose of glyphosate recommended for Caryocar brasiliense crop, respectively". The evaluations were performed at 24 h and 60 days after application. Visual and anatomical evaluations did not change regardless of the dose, while the histochemical evaluation showed an accumulation of starch grains in leaf tissues. There was an increase in the photosynthetic rate, in the electron transport rate, and in the effective quantum yield of photosystem II at 24 h after application. At 60 days after the application of the treatments, the photosynthetic rate showed a slight decrease and the transpiratory rate showed quadratic behavior. An increase in plant height was observed up to the dose of 480 g ha-1, a linear increase in stem diameter and a decrease in the number of leaves with increasing glyphosate doses. These results show that the cuticle protected the plant, and that the little absorbed glyphosate increased photosynthesis and transpiration to favor the plants. We can conclude that the H. courbaril species is able to survive after contact with glyphosate during the evaluated time, with no visual and/or anatomical damage, showing increases in growth and physiological characteristics for the tested doses.

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-3KCl) 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.

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.

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.

The production of quality seedlings coupled with the correct choice of fertilizer doses/sources and the container type are essential in the planting of forest species. Thus, the objective of this study was to evaluate the relationship between morphological, physiological and anatomical characteristics and container volume with different fertilizations on Acrocarpus fraxinifolius seeds seedlings. The experiment was conducted in a 2 x 8 factorial scheme (2 volumes of containers and 8 fertilizations), tested in polypropylene tubes of 50 and 110 cm³ and according to different fertilizations: control without fertilization; 4 increasing doses of Osmocote® Plus: 3, 5, 7, 9 kg.per.m³ of substrate, respectively; and 3 split mineral fertilizers with coverings. It was possible to note that the tube with the greatest volume of 110 cm³ presented the best results regarding the morphological characteristics, however, when analyzing the physiological variables it was clear that the 50 cm³ tubes present similar results to those of larger volume when well fertilized. Split fertilization presented better results than slow-release fertilization, and 50 cm³ tubes were more sensitive to fertilization due to the lower volume. Thus, the use of 50 cm³ tubes with fertilization is recommended for producing A. fraxinifolius seedlings, due to presenting physiological quality and economy of inputs in nursery production, transportation and planting.

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.

Common bean (Phaseolus vulgaris) cultivation occurs mainly in regions with acidic soils, where high aluminum (Al) concentration is a major constraint to crop production. In this study, we evaluated tolerance and sensitivity traits to Al exposure and calcium (Ca) deficiency in bean plants, and determined the efficiency of Ca to mitigate the toxic Al effects. Two bean cultivars (BRS Estilo and Campos Gerais) were grown in three soil conditions: (I) soil liming with calcium hydroxide Ca(OH)2 and Al unavailable (-Al+Ca); (II) fertilized soil with calcium nitrate [Ca(NO3)2·4H2O] and Al available (+Al+Ca); and (III) soil without Ca addition and Al available (+Al-Ca). At the beginning of the reproductive stage, we evaluated the photosynthetic processes, mineral nutrition, and leaf anatomy and morphological traits of plants. The photosynthetic parameters were good tools for monitor Al sensitivity in bean. +Al+Ca soil treatment mitigated the deleterious effects of Al on growth and mineral nutrition of both bean cultivars. However, Ca did not prevent the toxic effects of Al on leaf anatomy. Al stress and Ca deficiency caused negative effects on nutrient content, photosynthetic activity and leaf anatomy of bean plants. Calcium mitigated Al toxicity, primarily in the Campos Gerais cultivar, showing the potential to improve bean crop productivity in acid soils.

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.

O jacarandá-da-Bahia (Dalbergia nigra) tem elevado potencial para o manejo florestal sustentável, além de produzir madeira muito utilizada na fabricação de móveis e instrumentos musicais. Objetivou-se com este estudo avaliar os efeitos e interações que as doses de nitrogênio e inoculação com Rhizobium promovem em mudas de D. nigra, em casa de vegetação utilizando Latossolo Vermelho Distrófico. Para condução do experimento, foi utilizado o delineamento inteiramente ao acaso, composto por 5 doses de nitrogênio (0, 50, 100, 200 e 400 mg/kg de N), com e sem inoculação de Rhizobium específico para jacarandá (BR 8404), 3 procedências de sementes (Lavras, MG; Rio Doce, MG; e Santa Tereza, ES). As características morfológicas analisadas foram: biometria, biomassa e qualidade das mudas de D. nigra. A adubação com 217,5 mg/kg de nitrogênio influenciou todas as características morfológicas, onde a procedência Rio Doce teve melhor resposta às doses de N. A inoculação com Rhizobium se mostrou mais efetiva em doses mais baixas de adubação nitrogenada. Sendo assim foi possível constatar que as procedências de D. nigra, Rio Doce e Santa Teresa, respondem a adubação nitrogenada e que para as mesmas a inoculação apresentou resultados positivos.