Print version ISSN 0006-8705
MACHADO, CYNTHIA TORRES DE TOLEDO; FURLANI, ANGELA MARIA CANGIANI and MACHADO, ALTAIR TOLEDO. PHOSPHORUS EFFICIENCY INDEX OF LOCAL AND IMPROVED CORN VARIETIES. Bragantia [online]. 2001, vol.60, n.3, pp. 225-238. ISSN 0006-8705. http://dx.doi.org/10.1590/S0006-87052001000300010.
Local and improved corn varieties were evaluated to phosphorus (P) efficiency in nutrient solution and field. In nutrient solution, the experiment was set up at Instituto Agronômico, Campinas, São Paulo State, Brazil, during 1995-1996, in a randomized complete block design, with 5 replicates, in a factorial with three P concentrations (0.0645; 0.129 e 0.258 mmol.L-1) and ten maize varieties. In the field, the experiment was set up at the research center of Embrapa Agrobiologia, Seropédica, Rio de Janeiro State, Brazil, during 1998-1999, using a randomized complete block design, with 6 replicates, and 44 kg.ha-1 of P (100 kg.ha-1 of P2O5). The varieties used were Caiano de Sobrália, Carioca, Antigo Maya, Catetão, Pedra Dourada, Nitrodente, Sol da Manhã (BRS Sol da Manhã), BR 105, BR 106 and BR 107. Dry matter and, or grain yield, P content and P efficiency index were determined in plants of both experiments. The varieties Nitrodente and BR 106 showed the highest shoot dry matter in nutrient solution and the highest grain yield and efficiency index at field conditions. Catetão, with the lowest grain yield in field, showed also low shoot and root dry matter production in nutrient solution. The results in field and nutrient solution were also comparable for Pedra Dourada, BR 105, BR 107, Antigo Maya and Sol da Manhã (intermediary production). The exceptions were the varieties Carioca and Caiano, with inferior performance in nutrient solution and high grain yields in the field.
Keywords : Zea mays L.; genetic variability; nutrient solution; phosphorus nutrition.