Observations on Stomata and Hairs on Vegetative and Floral Organs in the Tribe Trifolieae (Family Papilionaceae)

Abstract

The structure of stomata and hairs and stornatal ontogeny are described in 12 species of the tribe Trifolieae.

Stomata may be paracytic, anisocytic, diacytic, haplocytic, and of transitional forms between diacytic and paracytic types. The most frequent types are paracytic, anisocytic, anomocytic and haplocytic. In any one species the most frequent type varies with the organ, and the pattern throughout the plant is not the same in every species. In general anomocytic stomata are most frequent on both surfaces of leaflets, and paracytic on stems.and petioles. On this basis the members of this tribe seem to have some uniformity. The ontogeny of stomata with subsidiary cells is mesogenous or meso- perigenous, or rarely perigenous. Anomocytic stomata are perigenous. The number of subsidiary cells is increased by (i) wall formation in the subsidiary cells, (ii) neighbouring perigenes assuming the form of subsidiary cells, or (iii) both processes operating in the same stoma simultaneously. Abnormalities such as contiguous stomata, stomata with one guard cell, and arrested development of stomata are occasionally met with.

Hairs may be glandular or eglandular ; both types are present in all organs, except in a few cases. Some uniformity in the members of the tribe is also observed in the structure of glandular and eglandular hairs.