چکیده
|
The Scutellaria is a Labiatae genus (subfamily Scutellarioideae) with a highly specialised
floral structure. The genus is characterised by a peculiar two-lobed calyx with a
projecting appendage, named the scutellum. Here, we present a detailed analysis of
floral development, using epi-illumination light microscopy, to clarify open questions
about its floral organisation. Floral whorls appeared in an acropetal sequence, with a
marked temporal overlap of petal and stamen appearance. Organ appearance in each
whorl proceeded unidirectionally from the abaxial to the adaxial side. Significant
developmental features included the formation of the scutellum, reduction of sepal
lobes and formation of a three-lobed nectary disc. Our study revealed that both loss of
organ initiation and fusion of primordia are responsible for the reduction in sepal
members in Scutellaria. The nectary structure was markedly different from most other
studied Lamiaceae.
|