Abstract

MARCHIORI, Luis Fernando Sanglade; CAMARA, Gil Miguel de Sousa; PEIXOTO, Clóvis Pereira  and  MARTINS, Mônica Cagnin. PERFORMANCE OF SOYBEAN (Glycine max (L.) Merrill) CULTIVARS SOWN DURING NORMAL AND 'SAFRINHA' SEASONS. Sci. agric. [online]. 1999, vol.56, n.2, pp. 383-390. ISSN 0103-9016.  http://dx.doi.org/10.1590/S0103-90161999000200018.

The present work was carried out to evaluate comparatively three soybean cultivars managed under five plant population densities, cultivated in the normal and in the safrinha growing seasons. Soybean cultivars, "IAC-17" (early), "IAC-12" (semi-early) and "IAC-19"(intermediate) were cultivated in a constant spacing of 0.50 m and with 10, 15, 20, 25 and 30 plants.m^-1. A randomized block design with 15 treatments (3 cultivars x 5 plant densities) was used in, each season, with three replications, three times. Each plot had 5 lines, 5 m long . The following parameters were estimated: final plant height, first pod insertion height, diameter of the main stem, number of branches per plant and bending. In the safrinha growing season, the intermediate cycle soybean cultivar, (IAC-19), presented the best performance. The delay in sowing in the normal growing season, as compared to the safrinha season reduced the ripening cycles of the plants with the highest soybean plant density in the line, the highest plant final height, the smallest main stem diameter, the smallest number of branches per plant, independent of the sowing season.

Keywords : soybean; cultivar; safrinha growing season; population.