Effect of Different Levels of Nitrogen Application on Yield and Yield Components of Quinoa (Chenopodium quinoa L.) Under Different Planting Densities

In order to investigate the effect of application of different levels of nitrogen on yield and yield components of quinoa under different planting densities, a factorial experiment was conducted in a randomized complete block design with three replications in the crop year 2019-2020 in Gonabad. Planting density treatments were at four levels (30, 50, 70 and 90 plants per square meter) and nitrogen levels were at four levels (zero, 50, 100 and 150 kg ha-1). The results of mean comparison showed that increasing the density from 30 to 90 plants per square meter increased plant height, Cluster dry weight and seed nitrogen percentage, and increasing nitrogen to 150 kg ha-1 increased plant height, number of clusters per plant, Cluster dry weight, number of sub-clusters per major cluster and seed nitrogen percentage. Also, the interaction effect of planting density and nitrogen application on leaf area index, number of seeds per plant, 1000-seed weight, Field efficiency of nitrogen consumption, seed yield, seed yield to leaf area index per plant, biological yield and harvest index were significant. Based on the results of interactions, the highest number of seeds per plant, 1000-seed weight, and seed yield, seed yield to leaf area index per plant and harvest index were obtained under the density of 50 plants per square meter and application of 100 kg ha-1 nitrogen. Due to the superiority of the level of 100 kg ha-1 nitrogen and the density of 50 plants per square meter in terms of seed yield, it seems that this level of density and nitrogen is recommended to achieve proper yield in the test area and similar areas.