Urban refuse compost bioassay: Germination and seedling performance of cress (Lepidium sativum L.), psyllium (Plantago ovata Forsk) and cumin (Cuminum cyminum L.)

In this study germination in vitro and in sand/compost mixture of cress (Lepidium sativum L.)، psyllium (Plantago ovata Forsk) and cumin (Cuminum cyminum L.) were evaluated. The aqueous extracts of compost strongly inhibited plant germination and root growth. The germination index values obtained for compost extracts were low، when compared with that of the control. Latent toxicity of compost for different plant species seemed not to be severe. However، when psyllium and cumin were germinated in a sand/compost mixture (25/75 and 50/50)، germination of cress was completely inhabited، with a sever reduction of the psyllium and cumin root growth. To avoid negative effects of compost on crop، routine germination bioassay should be included in education program for farmers. This showed enhance marketing and consumer acceptance of urban composts.