Yield and chemical constituents of Dragon’s head (Lallemantia iberica Fisch. et Mey) as influenced by planting date and spacing

Objective: Agricultural strategic decisions, like planting dates and spacings, have direct impacts on sustainable crop production. This experiment aimed to investigate the effects of different planting dates and spacing on grain yield and chemical constituents of dragon’s head (Lallemantia iberica Fisch. et Mey).Methods: A split-plot design based on a randomized complete block design with three replications was carried out to study the influence of planting dates (March ۱۸, April ۲, and April ۱۸) and spacing (۲۰×۳, ۲۰×۵, and ۳۰×۲ cm inter- and intra-row spacing) on L. iberica at Urmia University, Iran, in ۲۰۱۸. Seeds of dragon's head were provided by the Agricultural Research, Education, and Extension Organization, Urmia, Iran. Seeds were sown on three specified planting dates by hand at a depth of ۲ cm in plots of ۱۵۰×۲۰۰ cm. Then, they were covered with a thin layer of soil.Results: The maximum grain yield (۵۲۰ kg/ha), grain oil percentage (۳۱.۸۴%), and grain oil yield (۱۶۵ kg/ha) were obtained from the March ۱۸ planting date with ۳۰×۲ cm spacing. Also, the highest biomass (۳۷۹۶ kg/ha), essential oil percentage and yield (۰.۳۴% and ۱۳.۱۷ kg/ha, respectively), mucilage percentage and yield (۱۵.۳۰% and ۷۰ kg/ha, respectively) were observed on the March ۱۸ planting date. The maximum percentage of grain nutrients (NPK) was obtained from the earliest planting date and the planting spacing of ۲۰×۵ cm. The highest percentage of total unsaturated fatty acids against the lowest saturated fatty acids (stearic and palmitic acid) belonged to March ۱۸. However, the highest percentage of some of the important compounds in the L. iberica essential oil, including thymol, caryophyllene oxide, and phytol, was obtained on April ۱۸.Conclusion: Early planting on March ۱۸ was a better date for L. iberica, which gave a higher grain yield than other planting dates. Mutually, late sowing reduced the nutrient uptake, biomass, and some quality traits. Also, spacing of ۳۰×۲ cm with lower plant density showed better results in terms of plant quality.

کلیدواژه ها:

Essential Oil ، Fatty acids ، Mucilage ، Nutrients ، Plant Density