GRAIN-YIELD, BIOMASS AND LEAF-AREA OF TRITICALE IN RESPONSE TO SOWINGDATE AND CUTTING STAGE IN 3 CONTRASTING MEDITERRANEAN ENVIRONMENTS

The effects of sowing date and cutting stage on grain yield, biomass a nd leaf area were analysed in three spring triticale genotypes (x Trit icosecale Wittmack) grown at three different sites in Spain during 199 0/91. Results indicated that the most appropriate sowing date for grai n yield in these environments seemed to be from the last 10 days in No vember to mid-December. Cutting reduced grain yield, biomass and leaf area at anthesis, and these decreases were greater in a drier environm ent (the only exception being cutting at Zadoks growth stage (GS)31 at Lleida), and when the cutting was done at GS31 rather than GS30. The significant relationships found between the percentage loss in grain y ield and biomass and leaf area at anthesis after cutting suggest that genotypes intended for grain and forage production need to be able to regenerate leaf area rapidly after cutting.