No abstract

SummaryIn the present work, wood anatomy of Apollonias barbujana (Lauraceae) was investigated by both Light Microscopy and Scanning Electron Microscopy and compared with six taxa of the Lauraceae representing the tribes Laureae and Perseeae. The investigated species included four of the endemic Macaronesian taxa of the Lauraceae (Laurus azorica, L. novocanariensis, Ocotea foetens and Persea indica) in addition to Laurus nobilis and Persea americana. The recorded characters were analyzed by the NTSYS-PC program package, using the UPGMA clustering methods. The relationships between the studied taxa, expressed by average taxonomic distance (dissimilarity), were demonstrated as a phenogram. The study showed that Apollonias barbujana stood apart from the rest of the studied taxa of the Laureae and Perseeae by several unique features, predominantly uniseriate rays, multiseriate rays of 3 -5 rows, striated fibers and/or sclereids with thick walls and many bordered pits, excessive tylose deposits, vessels with wide scalariform perforations with 6 -12 bars and distinct bordered pits. More studies on this genus are needed. ZusammenfassungAnatomie

Macromorphological characters, SEM of seed coat surface criteria, seed coat anatomy and seed protein electrophoresis aspects, were used to reassess the taxonomic relationships between the genera Chaenomeles and Cydonia. Characters were analyzed by the NTsys-pc. program package, using the UPGMA clustering method. The dendrograms produced were discused and showed a close relationship between Chaenomeles sinensis Koehne and Cydonia oblonga Miller. The result gives support to the merging of the former taxon in the genus Cydonia as presented in Mabberley (1997).

Leaf and fruit cuticular features (cell form and / or epicuticular secretions) were studied in the Macaronesian endemic tree Apollonias barbujana (cav.)Bornm. using SEM and / or LM. In addition, the macromorphological and floristic aspects of the genus were surveyed. The results were then compared with similar features in 19 available taxa of the Lauraceae representing the tribes Laureae and Perseeae (Five taxa from the present study and 14 compiled from Literature). The data obtained were analyzed by the NT sys-pc program package using the UPGMA clustering method. The produced dendrograms were discussed. The study showed that Apollonias occupies a relatively isolated position in the family with affinities to both the Laureae and the Perseeae. The significance of cuticular features in the taxonomy of the Lauraceae was referred to, and a revision of the suprageneric classification of the family as suggested by Rohwer, 2000 is now strongly supported.

Criteria obtained by SEM of seed coat surface have been used to reassess the taxonomic relationships between 19 species belonging to three subgenera of the genus Sesbania. The produced characters were analyzed by the NTSYS-pc. program package using the UPGMA clustering method. The produced phenogram supported the treatment of the three taxa Agati, Daubentonia and Sesbania as subgenera in the genus Sesbania. SEM criteria have revealed that, the genus represent a natural monphyletic group and the subgenus Sesbania is the center of the genus from which the other subgenera could have been evolved.