Resgate vegetativo de árvores de Tectona grandis Linn F. pelo enraizamento de estacas

Abstract

RESUMO:O objetivo desse trabalho foi avaliar o enraizamento de estacas provenientes das brotações advindas da decepa e do anelamento do caule de árvores de Tectona grandis, assim como de estacas originadas do sistema radicular. Foram selecionadas árvores em plantios comerciais (propagados via seminífera) de 5, 10 e 15 anos de idade, na fazenda Bacaeri, localizada no município Alta Floresta, Mato Grosso. Foram selecionadas 20 árvores por idade, sendo aplicados os três tratamentos (decepa, anelamento e coleta de raiz). O experimento seguiu um arranjo fatorial (3 x 3), em delineamento estatístico inteiramente ao ocaso, considerando as três idades e os três tratamentos testados. Com os resultados obtidos foram verificadas diferenças significativas, para a brotação e número de brotos, em relação à idade, à técnica de resgate, não obstante não foram encontradas diferenças estatísticas na interação "idade x técnica de resgate". Quanto ao enraizamento das estacas, diferenças estatísticas foram observadas somente quanto à técnica de resgate. Os resultados indicaram que as técnicas de resgate, pela decepa e pelo anelamento do caule demostraram ter potencial no resgate vegetativo desta espécie. O resgate de árvores da teca pelo método da estaquia radicular, não se torna viável nas condições avaliadas, pelo fato da baixa taxa de enraizamento (4%) e não obtenção de brotações nas estacas.Palavras-chave: propagação vegetativa, silvicultura clonal, teca, estaquia. Redemption vegetative of the Tectona grandis Linn F. trees by the stakes rootingABSTRACT: The objective of this study was to evaluate the rooting of cuttings of shoots arising from coppicing and stem girdling of teak trees, as well as stakes originated the root system. Trees were selected in commercial plantations (propagated via seminiferous) of 5, 10 and 15 years old, in Bakirifarm, located in the city Alta Floresta, Mato Grosso, Brazil. Twenty trees were selected by age, the three treatments being applied (cuts off, annealingand root collection). The experiment followed a factorial arrangement (3 x 3) in experimental design entirely to the decline, considering the three ages and the three treatments tested. With the results obtained significant differences were found for the budding and number of shoots in relation to age, rescue technique, never the less there were no statistical differences in the interaction "old x rescue technique". As for root cutting, statistical differences were observed only on the rescue technique. The results indicated that the rescue techniques by cuts off and the stem girdling demonstrated a potential in vegetative recovery of this species. The rescue of teak trees by the method of root cuttings, does not be come viable under the conditions evaluated, because of the low strike rate (4%) and not getting shoots at the stake.

Genotype by environment interaction and teak (Tectona grandis L.) selection in Costa Rica

“…Since its creation, over 400 teak plus trees have been selected, cloned, and field tested by GENFORES members and collaborators. Field testing is done under different ecological conditions and in several countries of the region (Vallejos et al 2010, Espitia, Murillo and Castillo 2011, Correa et al 2013, Badilla, Xavier and Murillo 2016. In those trials, a moderate to strong genetic control with large genetic variation has been reported for diameter, commercial height, and commercial volume, i.e.…”

Induction of epicormic sprouts of Schizolobium parahyba var. amazonicum (paricá): effect of seasonality and stump height

“…According to this principle, epicormic sprouting occurs only when an adequate amount of carbohydrates is available to support the post-sprouting phases (Van den Ende 2014). Induction of epicormic sprouts has been linked to environmental factors such as response to solar irradiance on dormant buds, genetic variations between plants, as well as physiological, hormonal, and stress responses (Badilla et al 2016;Meier et al 2012). Kratz et al (2016) attribute the higher supply of epicormic sprouts at the base of Calophyllum brasiliense stumps, compared to the girdling technique, to the increased incidence of sunlight at the base of these stumps, resulting in the photo-oxidation of auxins and subsequently breaking bud dormancy.…”