Effects of drought stress on yield and morphophysiological traits of quinoa (Chenopodium quinoa Willd) at different levels of nitrogen

Objective: This study aimed to investigate the effect of drought stress and nitrogen fertilizer on grain yield and some morphophysiological traits of quinoa. Methods: A factorial experiment was performed for the quinoa Titikaka cultivar. The factors included three levels of water-deficit stress based on soil moisture depletion [۴۵% (control), ۶۵%, and ۸۵%] and three levels of nitrogen fertilizer including ۵۰ (control), ۱۰۰, and ۱۵۰ kg/ha.Results: The highest leaf area index in the first year was obtained at ۴۵% soil moisture depletion (without drought stress) and the highest chlorophyll index was obtained at ۶۵% soil moisture depletion level. In the second year, the highest leaf area index (۱۱.۳) and the highest chlorophyll index (۶۴.۲۰) were obtained from ۶۵% and ۸۵% soil moisture depletion combined with ۱۵۰ kg/ha of nitrogen fertilizer, respectively. In the first year of the experiment, the ۴۵% soil moisture depletion with ۱۵۰ kg/ha of nitrogen fertilizer had the highest number of panicles per plant (۱۳.۱). Also, the highest ۱۰۰۰-seed weight (۲.۴۷ g), grain yield (۱۹۲۶.۶۳ kg/ha), and plant height (۴۹.۱۵ cm) were obtained from the ۴۵% soil moisture discharge and ۱۵۰ kg/ha of nitrogen fertilizer.Conclusion: The population structure and genetic relationships of the Iranian bread wheat landraces presented here highlight their diverse genetic architecture. The results of this study provide valuable information for the utilization of landraces in the genetic improvement of bread wheat.

Keywords:

Chlorophyll , Nitrogen , Quinoa , Water shortage , Yield