Changes in seed vigour of Dragon’s head (Lallemantia iberica Fish. et Mey.) under irrigation and plant density treatments

Abstract A field experiment was conducted in 2012 to investigate the effects of different irrigation treatments and plant density on seed vigour of Dragon's head (Lallemantia iberica Fish. et Mey.). The experiment was arranged as split plot based on randomized complete block design with four replications. Irrigation treatments (I1, I2, I3, I4 and I5: irrigation after 70, 100, 130, 160 and 190 mm evaporation from class A pan, respectively) were assigned to main plots and four plant density levels (D1, D2, D3 and D4: 200, 300, 400, 500 plant/m2) were allocated to the sub plots. Different planting densities were employed by changing planting distances on cultivation rows. Electrical conductivity (EC) of Dragon's head seed leachates increased, but germination percentage, germination rate and seedling dry weight decreased with enhancing drought stress levels. Electrical conductivity, seed germination percentage, germination rate and seedling dry weight was not significantly affected by plant density. Reduction in these traits was related with ion imbalances and membrane disruption under drought stress. Thus, the quality of Dragon's head seeds could be influenced by well irrigation treatments.