Alessandro Camargo Ângelo

Uso de ectomicorrizas na biorremediação florestal.

This article presents an overview of the aspects of mycorrhizas and their use in forest species and bioremediation. The information gathered from the literature had already indicated that ectomycorrhizal fungi may be very important to stimulate the growth of seedlings and trees. As for bioremediation, these fungi are promising in the ability to degrade pollutants in contaminated soils. In this sense, the benefits and uses of these microorganisms, and the characteristics of ectomycorrhizae (ECM) are presented herein, which are promising for use in these processes. Also, information on the potential use of ECM for the remediation of persistent organic pollutants and heavy metals is presented, as well as some results already searched. It is shown that internationally, the focus of the research on mycorrhizae has occurred with new perspectives, beyond the conventional use to stimulate plant growth.

VEGETATIVE RESCUE AND ROOTING OF CUTTINGS OF DIFFERENT STOCK PLANTS OF Sequoia sempervirens

Sequoia is a fast-growing, long-living species, producing durable timber. The aim of this study was to test different methods for the vegetative rescue of Sequoia sempervirens trees over 40 years old, made at different periods of the year, and, later, testing the rooting of individualized cuttings in planned arrays. Twenty-four individual sequoias were rescued, applying girdling and semi-girdling at three different heights (-10, 0, and 30 cm). The first collection was made 90 days after application of the treatments, being repeated at 150, 240, and 360 days. The percentage of budding trees and the number of shoots per array were registered. In all collections, shoots produced cuttings, which were placed for rooting in mini-tunnels. Cutting survival (%), rooting (%), and number of roots were registered, per array, and per collection. The species vegetative rescue proved to be efficient for the production of shoots for stem cuttings, especially with girdling at 30 cm and semi-girdling at -10 cm. However, it is difficult to define the best method, mainly because of the genetic effect among stock plants. The rooting of cuttings, of recovered material, presented good results (average >65%), also with great differences among stock plants. The potential for rooting of cuttings varied according to different planting periods, with high rooting rates in all seasons, especially in summer. Sequoia sempervirens shows the potential for vegetative rescue and cloning by rooting of cuttings, and this may lead to new studies, with a view towards fixing clones. RESGATE VEGETATIVO E ENRAIZAMENTO DE ESTACAS DE DIFERENTES MATRIZES DE Sequoia sempervirens RESUMO: Sequoia é uma espécie de rápido crescimento, longeva e de madeira durável. O objetivo do estudo foi testar diferentes métodos de resgate vegetativo em árvores com mais de 40 anos de idade de Sequoia sempervirens, realizados em distintas épocas do ano e posterior enraizamento de estacas individualizadas por planta matriz. Resgataram-se 24 indivíduos de sequoia, aplicando-se anelamento e semianelamento em três diferentes alturas (-10, 0 e 30 cm). A primeira coleta foi efetuada 90 dias após aplicação dos tratamentos, sendo repetida aos 150, 240 e 360 dias. Contabilizou-se a porcentagem de árvores com brotações e o número de brotações por matriz. Em todas as coletas as brotações originaram estacas que foram colocadas para enraizar em estufim. No enraizamento das estacas analisou-se a sobrevivência (%), enraizamento (%) e número de raízes por matriz por coleta. O resgate vegetativo da espécie mostrou-se eficiente na produção de brotações para a estaquia, destacando-se o anelamento a 30 cm e o semianelamento a -10 cm. Entretanto, há dificuldade em definir qual o melhor método, principalmente em função do efeito genético entre matrizes. O enraizamento de estacas do material resgatado apresentou bons resultados (média >65%), também com grande diferença entre as matrizes. Diferentes épocas de estaquia alteraram o potencial de enraizamento, contudo, com altos índices de enraizamento em todas as estações do ano, principalmente no verão. Sequoia sempervirens apresenta potencial de resgate vegetativo e clonagem por estaquia, sendo possível conduzir novos trabalhos com vistas a fixação de clones.

EFEITO DE LODO DE PAPEL RECICLADO SOBRE O CRESCIMENTO EM DIÂMETRO DE COLO DE Eucalyptus saligna Smith.

The solid waste of recycling paper industry has potential to be used for the correction of soil acidity and as a source of nutrients for agricultural crops and forestry. This study aimed to evaluate the effects of recycled paper sludge on the stem diameter growth of Eucalyptus saligna Smith, based on a 4x2x5 factorial design, being the factors the dose of the sludge, the top fertilization and the days after treatment, during 120 days. Despite its promising use as corrective of soil, sludge recycled paper hindered the development of stem diameter, and the highest dose damaged the fertilization