The behaviour of eighteen wheat cultivars at three seeding times (March 21st to 31st April 20th to 30th and May 20th to 30th) was determined in experiments carried out at Taquari Farm, Paranapanema county, Center-South Region of the State of São Paulo, Brazil, in the period 1981-85. Grain yield, disease resistance, hectolitric weight 1,000 grain weight and number of grain per gram were evaluated for each experiment Soil water availability was obtained by water balances taken at each ten days, considering 125mm as the soil water retention capacity. The results showed that the seeding time from 21st to 31st of March was the best for grain yield. The disease occurrence was highly influenced by meteorological conditions, being the main pathogen Helminthosporium sp. The cultivar CNT 7 exhibited the best grain yield, mainly at the first seeding time. No correlation was observed between hectolitric weight and 1,000 grain weight; however the correlation between grain yield and 1,000 grain weight was positive and significant indicating the influence of this parameter on the yield. Considering the water balance of the Paranapanema Region plus the grain yield and its components, the third seeding date was marginal for the wheat crop.
wheat cultivar; water balance; leaf and stem rusts; Helminthosporium sp.; 1,000 grain weight