Interpretation of hybrid by sowing date interaction for 1000 seed weight in sunflower

Abstract

This paper investigates the effect of hybrid by sowing date interaction on the 1000 seeds weight in sunflower. The experiment included three sunflower hybrids (Miro, Rimi, and Pobednik) and eight sowing dates. The experimental design was a randomized block design with four replications over three years (2005, 2006 and 2007). For the analysis of hybrid by sowing date interaction linear-bilinear AMMI model (main effects and multiple interaction) was performed. Three-way analysis of variance showed highly significant (P < 0.01) contribution of year (46.2%), hybrid (27.4%) and sowing date (8.4%) on 1000 seed weight. All second and third order interactions were also highly significant. From the hybrid by sowing date interaction highly significant first interaction component (IPC1) was separated which explained 82.3% of the total variance. Based on the graphic presentation the similarity in interaction of hybrids Miro and Rimi was pointed out. With the highest mean value for 1000 seed weight, hybrid Pobednik was different from previous two hybrids, in both main effect and interaction. In the earlier sowing dates (R1, R2) the highest values were achieved, while from sowing date R3 the 1000 seed weight remarkable decreased. Correlations between climatic variables and IPC1 were found which provides agronomic importance in interpretation of the interaction.

Keywords

• AMMI model
• climatic variables
• sunflower
• 1000 seed weight