Delmar Santin

MANEJO DE COLHEITA E ADUBAÇÃO FOSFATADA NA CULTURA DA ERVA-MATE ( Ilex paraguariensis ) EM FASE DE PRODUÇÃO

Successive harvesting of leaves (FO) and thin branches (GF), with no nutrient reposition by fertilization, have been resulting in continuous decrease in Brazilian productivity of mate in the last 20 years. So, the objective of this work was to evaluate the influence of harvest interval and phosphate nutrition on the availability of phosphorus (P) in the soil, on the productivity, as well as on the nutritional status of mate plants. The experiment was conducted in Sao Mateus do Sul/PR, in an Oxisol, where doses of 0, 20, 40, 80, 160 and 320 kgha -1 of P 2 O 5 were evaluated for harvest intervals of 12, 18 and 24-months in a seven-year-old mate plantation. Soil P availability, at 0-10, 10-20 and 20-40 cm depth, was assessed. Harvest consisted on removal of approximately 95 % of the tree canopy formed since the previous harvest. Harvested green material was individually determined for FO, GF and thick branches (GG), where FO + GF corresponded to the commercial mate (ECOM). The relationship between green/dry mass (MV/MS) was also evaluated for all plant components, as well as the content of P in FO, GF and GG. Phosphate fertilization increased the availability of P in the upper soil layer and the plant responded positively to P application by increasing the dry mass of all the assessed components. Harvests with longer intervals resulted in greater productivity of ECOM, but for maximizing productivity, high doses of fertilizers are need ed. Twelve month intervals are insufficient to allow the plant to recover from the harvest impact, even if well-nourished in phosphorus.

Teor crítico de enxofre no solo para o estabelecimento de clones de erva-mate no Sul do Brasil

The cultivation of yerba mate ( Ilex paraguariensis St. Hil.) has great economic importance in the Southern of Brazil. However, the fertilization requirements in the establishment of yerba mate plantations is still unknown. The objective of this work was to evaluate the needs of sulfate fertilization on the initial growth of two clones of yerba mate in a Humic Cambisol. An experiment was carried out in Itaiopolis - SC and four doses of S (0.0; 1.2; 2.4 and 3.6 kg ha -1 of S-SO 4 2- ) and two clones (F1 and F2) were tested. The green mass and the export of nutrients were evaluated: leafs, fine twigs, thick twigs and commercial yerba mate (leaf + fine twigs), and total mass. Soil available S-SO 4 was evaluated in the 0-20 cm soil layer 24 months after planting. The production of thick twigs increased with application of S, for clone F2. However, the yield of fine twig and total mass were influenced by the dose of S, independent of the clone. Thus, there was a positive response from the application of sulfur to clone F2, indicating that it is demanding on the nutrient, increasing the yield of green mass and the levels of S-SO 4 in the soil.

Plant growth, nutrients and potentially toxic elements in leaves of yerba mate clones in response to phosphorus in acid soils.

Native to subtropical region of South America, yerba mate is responsive to P under some conditions, but the degree of influence of genetic and soil on the growth and composition of the leaf is unknown. The aim of study was to evaluate plant growth, nutrients and potentially toxic elements in leaves of yerba mate clones in response to P application in acid soils. In greenhouse condition, two yerba mate clone seedlings were grown (210 days) in pots, each clone in a completely randomized design in factorial scheme (with and without P; four acid soils). The elemental composition of leaves and the growth of plants were determined. Phosphorus promoted plant growth, but this was not accompanied by increased P in leaf tissue in all conditions tested. The P effect on the elemental composition varied: decrease/null (N, K, Mg, Mn, Cu, Ni, B, Mo, Al, Cd); increase/null (C/N, C, Ca, Fe, V); increase/decrease/null (Zn, Ba, Pb) and; null (Cr). The soils affect the elemental composition of the leaves, especially Mn, with accumulation greater than 1000 mg kg-1. The Ba, Pb, Al and Zn in the leaves varied among clones. Yerba mate response to P was affected by edaphic and plant factors.

CLONAL FORESTRY OF Araucaria angustifolia: PLANTS PRODUCED BY GRAFTING AND CUTTINGS CAN BE USED FOR WOOD PRODUCTION1

Araucaria angustifolia (pinheiro-brasileiro ou araucaria) e uma especie nativa potencial para a silvicultura brasileira. No entanto, uma serie de desafios e limitacoes tecnicas ainda persistem, dificultando sua expansao como especie para plantios florestais, dentre os quais se destaca a falta de avaliacao de tecnologias de clonagem de materiais geneticos em condicoes de campo. O presente estudo objetivou avaliar a potencialidade da utilizacao de mudas de araucaria produzidas por estaquia e enxertia para producao madeireira em comparacao as produzidas por sementes, por meio da avaliacao do vigor vegetativo a campo e assim estabelecer um fator de forma para plantios com idade equivalente. Mudas provenientes de estaquia e de sementes foram plantadas a campo em espacamento 3 x 3 m, sendo parte das ultimas destinadas a servirem de porta-enxertos para enxertia. O experimento foi conduzido num delineamento inteiramente casualizado, com tres tratamentos e parcelas de uma planta (one tree plot). Plantas provenientes de estaquia apresentaram maior crescimento em diâmetro a altura do peito (7,4 cm) e altura total (4,2 m) aos 74 meses apos o plantio, seguidas das mudas de enxertia e sementes, com resultados similares. Conclui-se que a estaquia e a enxertia sao tecnicas potenciais para a producao de mudas de araucaria para fins madeireiros, sendo, de modo especial, a enxertia recomendada pela facilidade de execucao, alem do fato de poder ser utilizada para formacao de pomares para producao de sementes e apresentar incremento volumetrico e fator de forma similar a mudas produzidas por sementes.

PHOSPHORUS FERTILIZATION AND HARVEST INTERVALS INFLUENCE ENERGETIC AND PHYSICAL PROPERTIES OF BRIQUETTES AND LARGE BRANCHES OF MATE

1 Received on 28.07.2015 accepted for publication on 16.09.2016. 2 Cambona Consultoria e Treinamento Agroindustrial Ltda, Santa Terezinha De Itaipu, PR – Brasil. E-mail: <desantinflorestal@yahoo.com.br>. 3 Universidade Federal dos Vales do Jequitinhonha e Mucuri, Mestrado em Ciência Florestal, Teófilo Otoni, MG Brasil. E-mail: <marcelinobreguez@yahoo.com.br>. 4 Universidade Federal de Viçosa, Departamento de Engenharia Florestal, Viçosa, MG Brasil. E-mail: <cassiacarneiro1@gmail.com>. 5 Instituto Federal de Santa Catarina, Canoinhas, SC Brasil. E-mail: <elibettiagro@yahoo.com.br>. 6 Universidade Federal de Viçosa, Departamento de Ciências do Solo, Viçosa, MG Brasil. E-mail: <nfbarros@ufv.br>. *Corresponding author.

Crescimento e nutrição de erva-mate influenciados pela adubação nitrogenada, fosfatada e potássica

A ocorrencia natural da erva-mate em solos acidos e com baixa fertilidade natural, levou essa especie a ser considerada de baixa exigencia nutricional, principalmente em relacao ao fosforo, embora pouco se conheca tambem sobre a exigencia de N e K. Diante disto, o objetivo deste trabalho foi avaliar o crescimento, teor de nutrientes no solo e em plantas jovens de erva-mate submetidas a doses de P combinadas com NK. Aplicou-se 0, 100, 200, 400 e 600 mg dm-3 de P2O5 combinados com 0, 50 e 100 mg dm-3 de N e K2O a um Latossolo Vermelho distrofico. Tres mudas de erva-mate foram transplantadas para vasos com 2,9 dm3 de solo. Aos 120 dias determinaram-se a altura, diâmetro do caule, comprimento e volume radicular e producao de materia seca da parte aerea e radicular das mudas. Determinaram-se os teores de N, P, K, Ca, Mg, Fe, Cu, Zn, Mn e Al das folhas e raizes, alem do conteudo de N, P, K, Ca e Mg. Amostras de solo foram submetidas a analise quimica. O crescimento da erva-mate foi afetado pela interacao entre P e NK, demonstrando melhor crescimento quando o teor de P no solo estava entre 18,5 a 28,6 mg dm-3 combinado com 100 mg dm-3 de N e K2O. Em doses superiores a 400 mg dm-3 de P2O5, as folhas passaram a apresentar clorose internerval, sintoma tipico de deficiencia de Fe. A ordem dos macronutrientes mais exigidos e que mais contribuiram para o crescimento da erva-mate foi P, N, K, Mg e Ca. A erva-mate cresce bem em solos com altos teores de P, mas depende da boa disponibilidade de N, K e Ca.