Temperatures affect differently plant development, floral differentiation, head size and quality, yield, and duration of hoticultural cycle of broccoli cultivars (Brassica oleracea L. var. italica Plenck). The use of cultivars tolerant to higher temperatures allows expanding growing areas, scheduling planting dates, broadening product marketing, besides increasing crop returns. The objectives of this study were to evaluate the yield, horticultural cycle and yield distribution throughout the harvest period of eight broccoli cultivars spring-sown in the central area of Rio Grande do Sul State, in southern Brazil. The experiment was carried out at the Federal University of Santa Maria on Vacacaí soil. Twenty four-day-old seedlings were transplanted on 20 Nov1996, at the rate of 14.200plants ha-1, to 9,80m² experimental units laid out in a randomized block design replicated four times. Data were collected for yield of marketable center and lateral heads harvested at 2-3 day intervals. There were significant differences among cultivars for yield of marketable center and lateral heads and for total marketable yield. The yield of center heads, main component of 'Baron' and 'Hana Midori', was significantly higher than the remainder cultivars. The yield of lateral heads was the major component of total marketable yield for six cultivars. 'Piracicaba Precoce' and 'Piracicaba Precoce de Verão' were the highest-yielding cultivars for lateral heads, and both differered significantly. The horticultural cycle averaged 134 days, and the mean harvest period lasted 37 days for all cultivars There were marked differences among cultivars for weekly yield distribution of center and lateral heads.
Brassica oleracea var. italica; planting time; productivity; weekly yield distribution
