Document Type : Full Paper
Authors
1
Ph.D. Candidate, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
2
Professor, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
3
Associate Professor, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
4
Assistant Professor, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
Abstract
In order to evaluate the yield of the Motherwort (Leonurus cardiaca) ecotypes in water deficit stress, an experiment was carried out in randomized complete block design under a split plots arrangement, with three replications. Three irrigation levels were considered based on field capacity (FC) (as control), one third and two third of FC as main plots. Sub plots were formed by the four ecotypes of Leonurus cardiaca. In this study, the effects of water deficit stress on dry matter, essential oil percentage and yeild were measured. In addition, stress tolerance index including Stress Susceptibility Index (SSI), Tolerance (TOL), Mean Productivity (MP), Stress Tolerance (STI), Geometric Mean Productivity (GMP) , Harmonic Mean (HM) were calculated in terms of dry yield in different water stress conditions. Results indicated that water deficit stress had a significant effect on dry matter, essential oil percentage and yeild. Results also showed that the GMP, HM, MP indices were more appropriate indices for identification of drought resistant plants of Motherwort. According to stress indices, the ecotype of Khansar was the most drought tolerant ecotype in comparison to other ecotypes in the mild and severe water stress environments and contained high dry matter yield and essential oil percentage and yeild. Sarab was the most susceptible ecotype among the studied ecotypes with low dry matter and essential oil yeild despite high essential oil percentage.
Keywords