A field experiment was carried out at Embrapa Amazônia Ocidental (Agroforestry Research Center for the Western Amazon) in Iranduba county, AM, from September to December 1995, to evaluate nine cultivars of summer cabbage: União, Master, Shutoku, Saikô, Sooshu (control), XPH - 5786, XPH - 5787, XPH - 5904 e XPH - 5909 in a Low Humic Gley soil, floodplain ecosystem. The first five cultivars are commercial cabbage and the others experimental hybrids. The experimental was laid out in a randomized block design with four replicates and twenty plants, at planting distances of 0.80 m x 0.40 m. Due to the native high levels of nutrients in floodplain soils, only N and B fertilizers were used. Necessary irrigation and cultural practices were conducted for cabbage cultivation. Hybrids Saikô (12.5 kg) and Sooshu (15.0 kg) produced highest yields per plot and the lowest by hybrids Master (7.0 kg) and cv. União (6.0 kg). Hybrids Sooshu (810.6 kg), Shutoku (719.1 g) and Saikô (698.0 g) produced the greatest head weight. Hybrids Saikô and Shutoku produced the most compact heads. In hybrids Shutoku and Saikô heads were slightly flattened, a trait of commercial preference, and flattened in Sooshu (control); and in the other cultivars were slightly lengthened in shape. For depth of core (core length/longitudinal diameter) only hybrids Master and Shutoku had depreciated values (0.62 and 0.64, respectively). The most early hybrids were Sooshu (75 days), Shutoku (84 days), Saikô (84 days), and cv. União (85 days) and the latest hybrid XPH-5787 (92 days). It was concluded that the hybrid Saikô produced the most consistent set of desirable characteristics with good adaptation to the soil and climatic conditions of the floodplain ecosystem. It is recommended that his hybrid be tested in larger experimental areas, in this ecosystem.
Brassica oleracea var. capitata; hybrid; cultivar; ecosystem; lowland varzea