NULLA palynological and multivariate study of six species of Tamarix L. distributed in
Egypt was carried out. Pollen morphology was examined by Light Microscope (LM) and
Scanning Electron Microscope (SEM). The systematic study of these species was
conducted by means of numerical analysis using UPGMA clustering and PCO analysis
based on 33 morphological characters, including life form, vegetative parts, fruits, floral
characters, seeds and pollen grains. Pollen grains were found to be monads, radially
symmetrical, isopolar, small-sized and homocolpate. Tamarix nilotica can be easily
separated from other taxa by its subprolate pollen shape. Two major clades were
identified by multivariate analysis of morphological characters; one of them included
three species, namely T. amplexicaulis, T. passerinoides and T. macrocarpa. Our results
indicate that there is a wide range of morphological similarity among the species of
section Polyadenia. The other clade included T. aphylla, T. tetragyna and T. nilotica from
section Tamarix and section Oligadenia.