PRINCIPALS OF FLOWERING PLANTS TAXONOMY
BOT 222
Dr. Najat Abdulwahab Bukhari
Lecture 12
University Vision and Mission
Vision:
To be a world-class university and a leader in developing Saudi Arabia’s knowledge economy
Mission:
To provide students with a quality education, conduct valuable research, serve the national and international societies and contribute to Saudi Arabia’s knowledge economy through learning, creativity, the use of current and developing technologies and effective international partnership.
Vision:
upgrading the academic and research to keep pace with scientific progress and requirements of society.
Mission:
Development of Academic process and develop scientific research through strategic planning and a clear vision for science and technology at the country level. As well as training of national cadres, and the introduction of a methodology developed to meet the different needs of society, and to serve the various research and developmental projects in the community
Botany department Vision and Mission
Course Description Topics to be Covered
Topic No ofWeeks
Contact hours
- Historical review of plant taxonomy (industrial , natural, evolution)
1 2
- Nomenclature 1 2- Classic taxonomy (morphological taxonomy of vegetation and floral characters – Fruits and seed characters.
5 2
- Key to taxonomical unites. 1 2- Fertilization and seed formation 2 2- The different kinds of fruits 2 2- The sexual differentiations of flowers and their fertilization
2 2
14 14
Floral formula Floral formula is a summary of the structure and
components of a flower using symbols and numbers. The parts of the flower are represented by: K (for calyx) C (for corolla) P (for perianth) A (for androecium) G (for gynoecium) The symbol G has a line above it to indicate an inferior
ovary and a line beneath it to indicate a superior ovary
The sexuality of the flower is represented by the standard symbols for males (♂) and females (♀).
Bisexual
The symbols representing symmetry include: ygomrphic Actinomorphic Zygomorphic
"M" for a monoecious system and "D" when dioecious. (PM) polygamomonoecious (PD)polygamodioecious
∞ indicates an indefinite number of parts (more than 12).
( ) If the parts are fused. ….+…. if they are in separate groups * = staminode; a sterile stamen Ḡ = ovary inferior to insertion point of the
other whorls. G = ovary superior to insertion point of other
floral whorls Ḡ = ovary inferior to superior - variation exists
The structure of a flower is composed by the previous floral formula and appropriate symbols and the placentation type within the ovary. Any descriptive terms can be added to describe an important floral character such as the sub- calex or sterile stamens, etc. .....
How to dissect a flower
Using the above rules we can follow these steps and the observations:Floral Diagram:Floral diagram is the stylized cross sections of flowers that represent the floral whorls as viewed from above, showing the arrangement and number of parts in a flower, ovary is drawn as a cercal in the centre.Posterior sidePeduncle.
In the case of florets the focus is to the large flower (axis of the rest of the flowers).
If exists the bract is drawn at the bottom of the paint, to the Anterior side of the flower.The floral whorls represented by circles.
Longitudinal Section
1- parts of flower drawn by order of parts on the pedicles.
2- taking in consecration the ratio of the lengths of these parts maintaining the proportions of the real lengths .
Positions of sepals and petals do not represent the sector in the longitudinal and represent only the full parts and the fusion places of docking between the parts to each other while maintaining the ratio
The longitudinal sector shows the stamens position. Whether its out of pedicel or . And shows the various shapes of calyx.
Floral Diagram Symbols II
Sample floral diagrams
Sample Floral Diagrams Described
Distribution of sex in flowers
Poly sexual “ Mult sexual”
Poly gamy
Multi sexual flowers , male and
female flowers
Bi sexual
Dio gamy
Some flowers formed having stamens and
pistils :
Mono sexual
Mono gamay
Mixed pollination
Allo gamy
Mono sexual
Mono gamy
2 -Dioecious
Having the male and female organs in separate and
distinct individuals; having separate sexes
Phoenix dactylifera
1 -Monoecious
Having separate male flowers and female flowers on the
same plant, as in corn
Zea mays
Bi sexual
2 -Dichogam the condition of having
stamens and pistils mature at different times “Allo gamy “
followed with Auto gamy
1- Homogamy
the condition of having stamens and pistils mature
at the same time
Two situations:
Homogamy
Cleisto gamy
Failure of a flower to open, stamens and styles mature “self pollination.
Chasmo gamy
A flower which is chasmogamous opens
and exposes the stamens and styles.
Dichogam
Protogamy
Stamens mature before styles. As
in strawberry.
Protandry
Styles mature before stamens.
Compound family
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