The efficacies of some indigenous herbal dyes for use in staining plant materials were examined to obtain non-toxic, eco-friendly and cheap stains for use in plant histology. Dye extracts from Bixa orellana, Curcuma domestica, Lonchocarpus cyanescens and Pterocarpus osun were used to stain wood sections using the existing standard staining procedures with little modification. All the extracts had affinity for the fibre and vessel elements except the extract from L. cyanescens.The extracts from C. domestica and B. orellana had higher selectivity than those of P. osun for fibre. From the results of the absorbance curves, each of the dye extracts from all speciese had minimum of two peaks, indicating that they had two or more colour imparting chromophores except dye extract from C. domestica. All the dye extracts were acidic with pH range of 3.77 to 6.77. Therefore, this study shows that dye extracts from B. orellana, C. domestica and P. osun could be solitarily or in combination with artificial dyes for plant histological staining.

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This paper presents a synthesis of a comparative leaf anatomy (lamina and petiole) of five species of the genus Terminalia found in southwest Nigeria. Collections of plants were made from different locations in Southwest Nigeria as the geographic locations of the sites of collection were also geo-referenced with a GPS device. The samples were identified at the Herbarium of Botany Department, Obafemi Awolowo University (Ife), Nigeria, and were subjected to anatomical examinations. Quantitative data were subjected to statistical analysis and the characters vary significantly (P = 0.05). Anatomical characters which separate the taxa include petiole outline, epidermal features, vascular pattern, occurence of cortical and pericyclic fibres, presence/absence of, and types of trichomes etc, all found to be useful in identification of different species. The variations in the anatomical traits could be effectively used in taxonomic delimitation of the species and are helpful characters in determining the complexes in the genus such as adaptation of the species to xeric environments. The presence of 2-3 layers of palisade mesophyll cells in Terminalia mantaly, which is an adaptation of the species to drought, is diagnostic for the species. It is suggested that a comprehensive consideration of leaf lamina and petiole anatomy should be used as basis of taxonomy.

The foliar anatomy of 12 species of Asteraceae around Ile Ife in South Western, Nigeria was described. The distinguishing characteristics of taxonomic value include; venation patterns, areole shapes, number of veinlet endings, trichome types, arrangement of vascular bundles. Venation types are actinodromous, craspedodromous or camptodromous, the presence of rectangular areoles are predominant in the species studied and this show family characteristics. However, the presence of crystal druses in the areoles of C. odorata is of diagnostic importance. The type of vascular bundle in the leaf midribs is classificatory as it divided the taxa studied into two groups; vascular bundles are amphicribal in Bidens pilosa, Chromolaena odorata, Launaea taraxacifolia, Crassocephalum crepidiodes, Tridax procumbens and Vernonia cinerea and bicollateral in Ageratum conyzoides, Aspilia africana, Emilia praetermissa, Synedrella nodiflora, Tithonia diversifolia and Vernonia amygdalina.

Wood anatomy of five Cola species was investigated to identify and describe anatomical features in search of distinctive characters that could possibly be used in the resolution of their taxonomy. Transverse, tangential and radial longitudinal sections and macerated samples were prepared into microscopic slides. Characteristic similarity and disparity in the tissues arrangement as well as cell inclusions were noted for description and delimitation. All the five Cola species studied had essentially the same anatomical features, but the difficulty posed by the identification of Cola acuminata and Cola nitida when not in fruit could be resolved using anatomical features. Cola acuminata have extensive fibre and numerous crystals relative to Cola nitida, while Cola hispida and Cola millenii are the only species having monohydric crystals. Cola gigantica is the only species that have few xylem fibres while other species have extensive xylem fibre. These features have proved very functional and strongly of diagnostic value in the classification and delimitation of the studied Cola species.