عنوان مقاله [English]
Determine the optimal seed density is one of the most important aspects of crop management to reduce seed consumption (cost reduction) or increase yield per unit area. In this study, the response of four commercial wheat cultivars at different plant densities was evaluated at the research farm of the Faculty of the University of Tehran in 2019. The experiment was conducted as factorial based on randomized complete blocks design with four replications. Wheat seeds of four cultivars (Ghods, Mahdavi, Marvdashat and M75-5) were sown at five levels (200, 250, 300, 350, and 400 plants per square meter). Traits height, number of tillers and spikes, number of seeds per spike, 1000-seed weight, grain yield, biological yield, and harvest index were measured. The results of analysis of variance showed that the response of wheat cultivars to changes in plant density was significantly different in most traits except tiller number, grain yield, and dry matter per unit area. The response of wheat cultivars to plant density was a positive trend so that the highest grain and biological yield of all cultivars was obtained at higher densities (350 and 400 plants per square meter). Ghods wheat cv. with the tallest plant (86.5 cm) and high fertility spike (164 spike per square meter) was superior to Mahdavi, Marvdasht, and M75-5 cultivars. Overall, the results showed that the application of density of 350 plants per square meter can be considered as the best plant density for autumn commercial wheat cultivars in Karaj region and similar places, which prevented the surplus consumption of improved cultivars seed (cost reduction), in approved with many researchers.