The Effects of Sowing Density and Timing on Spike Characteristics of Durum Winter Wheat

Durum wheat ( Triticum durum Desf.) is the second most cultivated species of wheat after common wheat. In this study, the physical properties of ears and kernels of durum winter wheat were evaluated, focusing on the effects of sowing date and density. Understanding these properties is crucial for assessing the quality and technological utility of wheat. Three winter varieties of wheat, Komnata, Pentadur, and Auradur, were cultivated in the Małopolska Voivodeship of Poland. Two sowing dates (optimal and delayed) and three sowing densities (400, 500, and 600 kernels/m 2 ) were employed. Significant variations in morphological traits—including plumpness, uniformity, density, and kernel dimensions—were analyzed. The results indicated that while the sowing date significantly influenced spike characteristics and grain yields, the sowing density had minimal effects. For example, plants sown earlier produced longer spike rachis and higher grain yield, reflecting the correlation between sowing time and spike development. This study highlights that grain plumpness varied significantly due to sowing dates, with delayed sowing yielding higher plumpness percentages. However, the overall volumetric weight of the grains was lower than the standard, indicating suboptimal growing conditions in Małopolska. Ultimately, this research underscores the importance of selecting appropriate sowing dates for optimal developmental outcomes in durum wheat, particularly under atypical growing conditions. Moreover, the results obtained partially indicate that worse physical spike biometry parameters can, to some extent, play a role in determining better quality of grain yield.