Development of clonal matrices of australian red cedar in different substrates under fertilizer doses

Abstract

In order to evaluate fertilizers doses in different substrates for growth and development of clonal matrices of Australian Red Cedar [Toona ciliata var. australis (F. Muell.) Bahadur], an experiment was conducted in a greenhouse. Five substrates were evaluate, with proportions by volume, the first consisting of 100% of Multiplant florestal ® , the second of 50% vermiculite, 20% carbonized rice hulls, 20% soil and 10% coconut fiber, the third with 50% soil and 50% sand, the fourth was composed by 50% Multiplant florestal ® , 10% soil and 40% coconut fiber and the fifth with 65% of Multiplant florestal ® , 25% vermiculite and 10% carbonized rice hulls. The fertilizers doses applied were 0.0; 0.3; 0.6; 1.2; 2.4 of fertilization suggested by Malavolta (1980) for vases. The characteristics evaluated were: collar diameter of the matrices, production of dry mater by shoots, root system and total and accumulation of nutrients by shoot at the end of the experimental period of 150 days. The Australian Red Cedar plants have high nutritional requirements, as showed by the better development obtained with higher fertilizer doses than those suggested by Malavolta (1980). The substrate three provided the worst development to clonal matrices while the substrates 1, 4 and 5 provided the best environment for the development considering all the fertilizer doses and all variables.Index terms: Toona ciliata, plant nutrition, fertilization. RESUMOCom o objetivo de avaliar diferentes substratos com taxas de fertilizantes para o crescimento e desenvolvimento de matrizes clonais de cedro australiano [Toona ciliata var. australis (F. Muell.) Bahadur], foi realizado um experimento em casa de vegetação. Foram avaliados cinco substratos, com as proporções em volume, sendo o primeiro composto por 100% Multiplant florestal ® , o segundo de 50% Vermiculita, 20% casca de arroz carbonizada, 20% terra e 10% fibra de coco, o terceiro com 50% terra e 50% areia, o quarto com proporção de 50% Multiplant florestal ® , 10% terra e 40% de fibra de coco e o quinto com 65% Multiplant florestal ® , 25% vermiculita e 10% casca de arroz carbonizada. Para os níveis de fertilizantes aplicados, foram utilizadas 0.0; 0.3; 0.6; 1.2 e 2.4 da adubação sugerida por Malavolta (1980) para vasos. Foram avaliadas as características: diâmetro do colo das matrizes, produção de matéria seca de parte aérea, sistema radicular e total e o acúmulo de nutrientes na parte aérea das plantas ao final do período experimental de 150 dias. As plantas de cedro australiano apresentaram elevada exigência nutricional, visto que estimativas mostraram o melhor desenvolvimento das mesmas com doses superiores às sugeridas por Malavolta (1980). O terceiro substrato proporcionou o pior desenvolvimento para as matrizes clonais, enquanto os substratos 1, 4 e 5 proporcionaram os melhores ambientes para o desenvolvimento, considerando todas as doses de fertilizantes e todas as variáveis analisadas.Termos para indexação: Toona ciliata, nutrição de planta, adubação.

Root Morphology and Nutrient Uptake Kinetics by Australian Cedar Clones

“…A cedar crop can be established at low or high altitudes (up to 1,700 m), being more sensitive to higher altitudes (LORENZI et al, 2003;SOUZA;BARROSO;CARNEIRO, 2010). This species has a high nutritional requirement, as well as it less tolerant to soil acidity (BENATTI et al, 2012;BRAGA, 2011).…”