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Abrus precatorius – Rosary Pea, Rosarypea, Precatory Bean, Jequirity Pea, Bead Vine
Leaf Epidermal Micromorphology in the Systematics of Abrus (Papilionaceae) in Parts of Tropical West Africa.
by Agbagwa I. O., Bosa E. O. (2006)
in Asian J. Pl. Sci.5: 41 – 49 – DOI: 10.3923/ajps.2006.41.49 –
http://scialert.net/abstract/?doi=ajps.2006.41.49
Abstract:
Comparison of the leaf epidermis of three species (A. canescens Welw. ex Bak., A. precatorius L. and A. pulchellus Wall. ex Thw.) and a new collection of Abrus adanson (simply referred to as Abrus sp.) found in tropical West Africa was undertaken by simple microscopy.
The epidermal cells are irregular with wavy, sinuous or arcuate anticlinal walls, while the coastal cells are parallel, elongated and rectangular, terminating obliquely.
Six types of stomata: paracytic (laterocyclic), diacytic, anomocytic, anisocytic, staurocytic and contiguous, were observed in the species. Anomocytic stomata are absent in A. canescens.
The new collection Abrus sp., is distinguished from the other three species by its amphistomatic nature and possession of stomata in-groups of two or three bordered by six continuous subsidiary cells on its abaxial surface. It also has a Stomatal Index (SI) of 18.19, the highest in the genus.
The other species are hypostomatic. Simple unbranched trichomes (long and short category) occur on both leaf surfaces of the species except in the new collection Abrus sp. where trichomes are confined to the abaxial surface. Trichome Index (TI) of 3.79 on the abaxial surface of A. canescens was observed to be the highest in the genus.
Venation is of the camptodromous-brochidodromous type. Crystals are of common occurrence in the species.
The study was aimed at improving systematic information on the tropical West African species of Abrus, which is hitherto lacking and with the collection of a new species, stimulate interest on Abrus taxonomy and conservation in the region.
PLANT STOMATA ENCYCLOPEDIA 
