Variation in seed furanocoumarin content within the wild parsnip (Pastinaca sativa)

Furanocoumarins are restricted within the ripe seeds of Pastinaca sativa, the wild parsnip, to the vittae or oil tubes. The furanocoumarin content and composition of these organs vary with their location. Vittae on the inner or commissural side of the mericarp contained over 90% of the total furanocoumarin content of the seed; the relative abundance of the five furanocoumarin components also varies with seed side. The location of the seed within an umbel does not appear overall to affect furanocoumarin characteristics; however, the location of the seed among umbels is associated with significant differences in furanocoumarin content. The absolute amount of furanocoumarin present in seeds of primary and secondary umbels was approximately twice that of seeds in tertiary umbels. In the case of the wild parsnip, then, furanocoumarin distribution is not homogeneous, either through the plant or within the plant part in which it is localized.