Presence of inhibitors of germination in seeds of five umbellifer crops viz. fennel ( Foeniculum vulgare Mill.), cumin ( Cuminum cyminum L.), carum ( Carum copticum Benth. and Hook.), carrot ( Daucus carota L.), and coriander ( Coriandrum sativum L.) was demonstrated. The effect of seed exudates on the pattern of inhibition of germination of these seeds was also studied. Presence of exudates in general delayed germination although the time of maximum inhibition was different with different crop seeds. The inhibitory effect was high at an early stage in the case of carum and carrot and persisted in the latter but disappeared in the former. The inhibitory effect on cumin and fennel increased up to the seventh day and then began to decrease. Growth of root and hypocotyl of 16-day-old seedlings was also inhibited by the exudates.