INTERACTION HYBRID × PLANTING DATE FOR OIL YIELD IN SUNFLOWER

The aim of the study was to assess the effects of hybrids andplanting dates as well as their interaction on oil yield in sunflower for three-yearexperiment (2005, 2006, 2007). Three sunflower hybrids (Miro, Rimi andPobednik) and eight planting dates were included in the experiment. AMMI(Additive Main Effects and Multiplicative Interaction) analysis is one of the mainlyused multiplicative models, which evaluates main effects and also interaction. Theinteraction was detected by using AMMI1 biplot. Oil yield was predominantly influenced by the year of growing (58.9%), then by planting date (12.9%) and by hybrid (10.7%). All interactions were significant as well. AMMI ANOVA showedhigh significance of both IPC1 and IPC2. The contribution of IPC1 was 77.5%.Hybrids Miro and Pobednik showed no significant differences in the mean values, which were higher than average. However, the hybrid Miro showed the higheststability for oil yield. Hybrid Rimi, with the lowest mean value, was the mostunstable for the examined character. Oil yield was higher in earlier than in laterplanting dates. Graphical presentation of AMMI1 in the form of biplot couldfacilitate the choice of stable hybrids and planting dates for desired characters insunflower