Dose- dependent effect of vermicompost and its extract on seed germination and vegetative growth of Nigella sativa

In this research the first experiment was performed in order to evaluating effect of various concentrations (20, 40, 60, 80, 100 % by volume) of vermicompost extract on some indices of seed germination and seedling growth of Nigella sativa in petri dishes. In the second experiment the effect of solid vermicompost substitution with 4 levels (0, 25, 50, 75% by volume) on the emergence and vegetative growth of plant was investigated in a pot experiment. Results showed that 20, 40% concentrations of vermicompost extract increased germination capacity, germination value, germination max value and length of root, shoot and vigor index. Also 25 and 50% substitutions of solid vermicompost increased emergence indices and length, dry and fresh weight of root and aerial parts, content of a, b, total chlorophyll and carotenoid in 3 old month's plants significantly as compared to the control. But high concentrations of vermicompost or its extract reduced these parameters. Thus, the effect of vermicompost on seed germination and vegetative growth of plant is dependent on concentration.