الفهرس 
Historical IntroductionOnly 14 pages are availabe for public view
 |  | from | 221 |  |  |
| | | from | 221 | | |
Abstract
Summary
The present study was carried out in the Taxonomic Unit Lab (TUL) of Botany Department, Faculty of Science, Ain Shams University.
The macro-, micromorphological and palynological characters of 18 taxa belonging to 11 genera of family Plantaginaceae and Scrophulariaceae were examined to search for the infrafamilial relationships among the two families for taxa delimitation. These taxa were collected from different localities in Egypt, and identified according to Bailey (1949) for cultivated taxa and Boulos (2002) for wild taxa.
The technical approaches used in the present study are as in the following:
1) The macromorphological characters of the whole plant were recorded directly from the fresh specimens.
2) Light microscope was used to investigate the anatomical characters and the photos were taken by the aid of digital camera (Canon Power Shot G12).
3) The pollen characteristics were investigated using both LM and SEM.
4) The results obtained were represented in cumulative tables and plates.
5) The obtained character states and their codes (0, 1) were subjected to the numerical analysis using NTSYS-pc version 2.02 software package to
construct four dendrograms (macro-, micromorphological, palynological and combined one for all data).
The constructed dendrograms were discussed and compared with different taxonomic systems. The following remarks were concluded:
1. Macromorphological characters:
The most obvious variations of macromorphological characters are:
a) Absence of stem (acaulescent) in all Plantago taxa except P. albicans where the stem is present (caulescent) in a dwarf form. The stem is long in the 12 Scrophulariaceous taxa.
b) Presence of radical leaves in rosette form in all Plantago taxa while in the other taxa leaves are either cauline or basal and cauline together.
c) Tetramerous flowers in the Plantago taxa and Veronica while pentamerous in the remaining taxa.
d) Presence of exerted stamens in all Plantago taxa and Veronica while included in the corolla tube in the rest of taxa.
e) The results of numerical analysis and the dendrogram utilizing macromorphological characters (130 character states) have clearly showed the isolation of the six studied Plantago species from the other taxa. This result is in accordance with some earlier taxonomic treatments (maintaining of
Plantago as a separate monogeneric family). This finding contradictory with APG III (2009) and other works based on molecular evidence.
2. Micromorphological characters:
The most distinctive features are:
a) Presence of characteristic anatomical feature foliar endodermis in the six Plantago taxa while absent in the rest of studied taxa. However, this feature is very rare in the Angiosperms (Dickson & Weitzman, 6991).
b) The dendrogram utilizing 168 micromorphological character states have clearly showed the clustering of three studied Plantago species (P. albicans, P. crypsoides, P. ovata) with the Scrophulariaceous taxa (Antirrhinum, Kickxia, Linaria, Nemesia, Russelia, Scrophularia and Veronica ). This finding is congruent with APG III (2009) which supports the transfer of Scrophulariaceous taxa to the Plantaginaceae s.l.
3. Palynological characters:
The most distinctive palynological characters can be summarized as follows:
a) Verrucate sculpturing, pantoporate, apolar pollens, presence of operculum except in P. major, presence of annulus except in P. albicans, P. major. These features clearly isolate the six Plantago species from the other 12 Scrophulariaceous taxa.
b) The results from the palynological based dendrogram support the earlier views of some authors for maintaining Plantago as a separate monogeneric family (Plantaginaceae s.s.) and the remaining other studied taxa in Scrophulariaceae s.l. (this part is published in the Egyptian Journal of Botany (accepted)).
The combined dendrogram based on macro-, micromorphological and palynological characters suggests the remaining of six studied Plantago species as a separate family (Plantaginaceae s.s.) and the remaining of other studied taxa in Scrophulariaceae s.l. This result is contradictory with APG III 2009 and other works based on molecular data.
Only, the dendrogram obtained from micromorphological characters supports the transfer of Anarrhinum, Antirrhinum, Digitalis, Kickxia, Linaria, Russelia and Veronica to Plantaginaceae s.l.
In general, numerical analysis of all attributes especially those of palynology confirms its efficiency in solving some taxonomic problems.
Concerning the taxa under the present investigation and for more accurate assignment of some Scrophulariaceae to Plantaginaceae, the reclassification demands more taxonomic criteria and much number of taxa.