Response of winter wheat to diversified sowing date and sowing density

Common wheat (Triticum aestivum L.) is the most important cereal in the world because its grains serve as the primary food for humans and also constitute good fodder for animals. Among the important aspects of the agronomy of this species are the sowing date and sowing density, as both affect yield components and grain yield. A three-year field experiment investigated the response of winter wheat to varying sowing dates (recommended, delayed by 30 days and delayed by 60 days) and sowing densities (recommended, increased by 10% and increased by 20%). It was demonstrated that the soil plant analysis development (SPAD) index, number of grains per ear, and thousand seed weight (TSW), were the highest when the seeds were sown at the recommended sowing date and density. On the other hand, the highest leaf area index (LAI) and the number of ears per square meter were obtained when the seeds were sown at the recommended sowing date but with a 20% increased sowing density. Delaying the sowing date, especially by 60 days, reduced grain yield. Increasing seed sowing density by 10% was beneficial when sowing was delayed by 30 days. However, increasing the density of sowing postponed by 60 days did not produce the expected results. The protein content in the grain exceeded 14% at the optimal sowing date and recommended sowing density, as well as when the sowing date was delayed by 30 days, and the sowing density was either recommended or increased by 10%. It should therefore be concluded that delaying the sowing date of winter wheat, especially by 60 days, is unjustified in the study area. For sowings delayed by 30 days, the decrease in yield can be partially compensated by increasing the sowing rate by 10%.