Haroldo Nogueira de Paiva

Efeito da aplicação de cádmio sobre o teor de nutrientes em mudas de cedro ( Cedrela fissilis Vell.).

With the objective of verifying the effect of the cadmium application on the nutrients content in cedro seedlings an experiment was installed in the greenhouse of the Department of the Soil Science of the Federal University of Lavras. The experiment followed a statistical delineation of randomized blocks, where the seedlings were cultivated in Clarks nutrient solution and submitted to the increasing levels of Cd: 0, 22, 44, 88 and 132 mM, using as source the cadmium chloride. After 60 days of display to the heavy metal, the plants were picked up and separated in root, stem and leaf. These parts of the plants were analyzed with relationship to the Cd, macro, and micronutrients content. The results showed that for the macronutrients it had an increase in the contents of P, S and Ca; practically no effect on the content of K was observed and the Mg content presented answer differentiated with the plant part. For the micronutrients, there was observed that it had on increase in the content of Cu and Fe and reduction in the content of Mn and Zn in the root; in the stem it had an increase in the content of Cu and Zn and reduction in the content of Fe and Mn, while in the leaf it had increase in the content of Fe and reduction in the content of Cu, Mn and Zn. The Cd content in the parts of the seedlings has increased with the dose of the applied heavy metal.

Teor, conteúdo e índice de translocação de nutrientes em mudas de cedro ( Cedrela fissilis Vell.) submetidas a doses crescentes de zinco.

Resumen pt: Com o objetivo de avaliar os efeitos de doses crescentes de Zn sobre o teor, o conteudo e o indice de translocacao de nutrientes, mudas de cedro foram c...The aim of this work was to evaluate the effects of the increasing levels of Zn on cedro ( Cedrela fissilis Vell.) seedlings. The experiment was conducted in Clark nutrient solution, in a greenhouse of the Soil Science Department of the Federal University of Lavras. The plants were submitted to increasing levels of Zn: 2, 76, 152, 304 e 456 µmol L -1 , in randomized blocks statistical design. At the end of 60 days of growth, evaluations were made of macro and micronutrients content and accumulation in the root, stem, leaf, shoot and total dry matter. It was also estimated a translocation index of these nutrients. The results show that, in a general way, there was different response to content and reduction in the macro and micronutrients accumulation, independent of the part of the plant analyzed, while the translocation index was increasing with the levels of applied Zn.

Produção de mudas de canafístula cultivadas em latossolo vermelho amarelo álico em resposta a macronutrientes

Peltophorum dubium (canafistula) is a fast-growing, rustic species excellent for use in combined reforestation of degraded areas. The objective of this study was to evaluate the effect of doses of N, P, K, Ca, Mg and S on seedling growth and quality indices; and to determine the recommended dose of these elements for establishment of a suitable fertilization program. The study was conducted in a greenhouse using red-yellow alic latosol as substrate. The experiment was designed following a Baconian matrix, evaluating three doses of the six macronutrients and two additional treatments, one with reference doses and another with no addition of nutrients. A completely randomized design was adopted with four replicates. Analysis using orthogonal contrasts revealed a signifi cant response from all variables being studied to application of macronutrients, except the H/D ratio. The nutrients P and N had the most signifi cant effects, 540 mg/dm3 being the recommended dose of P, and 50 mg/dm3 being the recommended dose of N. No response was observed to application of K, Ca, Mg and S, for most traits being assessed, indicating that the species has a low requirement for these nutrients.

EFEITO DO INTERVALO DE TEMPO ENTRE COLETA/PREPARO E ESTAQUEAMENTO NO ENRAIZAMENTO DE MINIESTACAS DE CLONES DE Eucalyptus urophylla x Eucalyptus grandis

This study aimed to assess the effects of the time interval between the collection/preparation and plantation on the rooting of minicuttings of four Eucalyptus urophylla x Eucalyptus grandis clones. The experimental design used was entirely randomized, bi-factorial and arranged with sub-divided plots, being time intervals in plots (0, 2 and 4 hours) and the clones in subplots (C 1 , C 2 , C 3 and C 4 ), with three replications of 192 plants each. The rooting and the survival of minicuttings in the greenhouse exit and in the shade house, the survival, the growth and the root system quality of 50-day-old seedlings were assessed. Among the four clones studied, it was observed, in three ones, that storage periods of the minicuttings above two hours caused significant reduction in the percentage of rooting and in the survival of 50-day-old seedlings . However, the clone C 2 presents the most efficient technique for rooting in the shade house exit and the survival of 50-day-old seedlings when their minicuttings are stored for 2.3 and 2.5 hours, respectively; as much as it presents greater height growth , when the minicuttings were stored during 4 hours. In all clones, those seedlings from minicuttings stored during 4 hours present lower quality of root system than plants obtained from cuttings with 0 and 2 hours of storage.

PHOSPHATE FERTILIZATION IN PRODUCTION OF Cassia ferruginea AND Cassia grandis SEEDLINGS

O objetivo deste trabalho foi avaliar o efeito da adubacao fosfatada e determinar a dose otima de fosforo (P) para o crescimento de mudas de Cassia ferruginea e Cassia grandis. Os tratamentos consistiram em seis doses de P (0, 150, 300, 450, 600 e 750 mg dm-3), dispostos em delineamento inteiramente casualizado, com quatro repeticoes e 25 mudas por parcela. Como recipientes foram utilizados tubetes de 55 cm³ de capacidade, preenchidos com substrato comercial a base de casca de pinus, turfa e vermiculita. Apos 120 e 230 dias da semeadura de Cassia grandis e Cassia ferruginea, respectivamente, foram avaliadas as caracteristicas: altura da parte aerea (H), diâmetro do coleto (DC), massa de materia seca da parte aerea (MSPA), da raiz (MSR) e total (MST), e calculadas as relacoes: H/DC, H/MSPA, MSPA/MSR e o Indice de Qualidade de Dickson (IQD). A adubacao fosfatada nao proporcionou resposta significativa (p < 0,05) no crescimento das mudas de Cassia ferruginea. Ao passo que o crescimento e a qualidade das mudas de Cassia grandis foram influenciados positivamente (p < 0,05) pelas doses de fosforo aplicadas. Conclui-se que a dose otima de P para a producao de mudas de Cassia grandis e de 500 mg dm-3.

MODELING Tectona grandis TREE AND STAND GROWTH USING STEM ANALYSIS AND PERMANENT PLOT DATA1

Menezes de Novaes, Daniel; de Albuquerque Santos, Ana Carolina; Boechat Soares, Carlos Pedro; Nogueira de Paiva, Haroldo; Gonçalves dos Reis, Geraldo; Monte, Marco Antônio; Siqueira Davila, Flávio; Garcia Leite, Helio MODELING Tectona grandis TREE AND STAND GROWTH USING STEM ANALYSIS AND PERMANENT PLOT DATA Revista Árvore, vol. 41, núm. 5, 2017, pp. 1-10 Universidade Federal de Viçosa Viçosa, Brasil

Propagação vegetativa do pau-jacaré (piptadenia gonoacantha (MART.) MACBR.) por estaquia

O objetivo deste trabalho foi desenvolver uma metodologia para a propagacao vegetativa do pau-jacare (Piptadenia gonoacantha) por meio da tecnica de estaquia, avaliando-se a sobrevivencia e capacidade produtiva das cepas em coletas sucessivas de estacas em jardim clonal e a sobrevivencia, enraizamento, altura, vigor e biomassa radicular e foliar das estacas, em funcao da aplicacao de diferentes dosagens (0, 2.000 e 6.000 mg L-1) do regulador de crescimento acido indolbutirico (AIB), do tipo de substrato (vermiculita e composto orgânico Mecplant®) e da posicao das estacas (apical, intermediaria e basal). Os melhores resultados foram evidenciados com as estacas apicais, utilizando o composto orgânico como substrato; no entanto, nas intermediarias e basais, a aplicacao de AIB, na concentracao de 6.000 mg L-1, foi a que mostrou valores medios mais elevados nas caracteristicas avaliadas, em casa de vegetacao, casa de sombra e pleno sol. A sobrevivencia das cepas foi de 100%, tendo a producao de brotacoes com tendencia crescente nas sucessivas coletas. Conclui-se que a propagacao vegetativa do pau-jacare, pela tecnica de estaquia com propagulos oriundos de mudas produzidas por sementes, foi tecnicamente viavel, principalmente quando se utilizaram estacas apicais ou intermediarias e basais, aplicando 6.000 mg L-1 de AIB e composto orgânico como substrato.