Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:22:43Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:28:45Z : No. of bitstreams: 1 2-s2.0-45949108720.pdf: 1110993 bytes, checksum: 751f157f99f614d27dd49aa78f219422 (MD5) Made available in DSpace on 2014-05-27T11:22:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-12-01 This paper evaluated the critical level, responsivity and boron use effciency on growth and the biomass production in six Eucalyptus grandis x Eucalyptus urophylla clones (Ca, Cb, Cc, Cd, Ce and Cf). An experiment was carried out in pots containing ground silicon, under greenhouse conditions using four boron rates per solution (0; 0.135; 0.27; 0.54 mg L -1 of B). The treatments were combined in a randomized block experimental design in a 4 × 6 factorial scheme with three replications. Plant height, stem diameter, dry matter production in the shoots of the plant and boron use effciency in the leaves, stem and total dry matter at the 8th month of age were evaluated. Due to boron fertilization, growth and shoot biomass were observed in the Eucalyptus plants after 240 days of being planted in pots. The increases in growth and biomass were 35 to 54% and 21 to 64%, respectively. The boron rates that promoted major growth of the plants were 0.33 to 0.44 mg L -1 of B and in this range the most effcient clone for dry matter production of leaves was Cf and the least effcient one to stem biomass production and the shoot biomass was Cd, no signifcant differences among other clones were observed. The critical level of boron in solution was 0.09 to 0.24 mg L -1 of B in the growth of the plants. Agronomia Pela Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Rua Emílio Menon, 268, Taquaritinga, SP - 15900-000 Departamento de Produção Vegetal Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, km 5, Jaboticabal, SP - 14884-900 Solos e Nutrição de Plantas pela Escola Superior de Agricultura Luiz de Queiroz Universidade de São Paulo, Rua Alfredo Guedes, 1949, Piracicaba, SP - 13416-901 Departamento de Pesquisa e Desenvolvimento Florestal da Votorantim Celulose e Papel, Rodo-via MS 395, km 20, Três Lagoas, MS - 79.601-970 Agronomia Pela Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Rua Emílio Menon, 268, Taquaritinga, SP - 15900-000 Departamento de Produção Vegetal Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Via de acesso Prof. Paulo Donato Castellane, km 5, Jaboticabal, SP - 14884-900