Presentation on theme: "Principals of Flowering Plants Taxonomy BOT 222"— Presentation transcript:
1Principals of Flowering Plants Taxonomy BOT 222 Dr. Najat Abdulwahab BukhariLecture 12
2University Vision and Mission To be a world-class university and a leader in developing Saudi Arabia’s knowledge economyMission: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.
3Botany department Vision and Mission 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
4Course Description Topics to be Covered Topic No of Weeks Contact hours- Historical review of plant taxonomy (industrial , natural, evolution)12- Nomenclature- Classic taxonomy (morphological taxonomy of vegetation and floral characters – Fruits and seed characters.5- Key to taxonomical unites.- Fertilization and seed formation- The different kinds of fruits- The sexual differentiations of flowers and their fertilization14
5Floral formula The parts of the flower are represented by: 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
6The sexuality of the flower is represented by the standard symbols for males (♂) and females (♀). BisexualThe symbols representing symmetry include:ygomrphicActinomorphic Zygomorphic "M" for a monoecious system and"D" when dioecious.(PM) polygamomonoecious(PD)polygamodioecious
7∞ indicates an indefinite number of parts (more than 12). ( ) If the parts are fused.….+…. if they are in separate groups* = staminode; a sterile stamenḠ = ovary inferior to insertion point of the other whorls.G = ovary superior to insertion point of other floral whorlsḠ = ovary inferior to superior - variation exists
8The 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
9How to dissect a flowerUsing 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.
10In 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.
13Longitudinal Section1- 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 .
14Positions 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 ratioThe longitudinal sector shows the stamens position. Whether its out of pedicel or . And shows the various shapes of calyx.
21Distribution of sex in flowers Poly sexual “ Mult sexual”Poly gamyMulti sexual flowers , male and female flowersBi sexualDio gamySome flowers formed having stamens and pistils :Mono sexualMono gamayMixed pollinationAllo gamy
22Mono sexual Mono gamy 2- Dioecious 1- Monoecious Having the male and female organs in separate and distinct individuals; having separate sexesPhoenix dactylifera1- MonoeciousHaving separate male flowers and female flowers on the same plant, as in cornZea mays
23the condition of having stamens and pistils mature at the same time Bi sexual2- Dichogamthe condition of having stamens and pistils mature at different times “Allo gamy “ followed with Auto gamy1- Homogamythe condition of having stamens and pistils mature at the same timeTwo situations:
24Homogamy Chasmo gamy Cleisto gamy Failure of a flower to open, stamens and styles mature “self pollination.Chasmo gamyA flower which is chasmogamous opens and exposes the stamens and styles.
25Stamens mature before styles. As in strawberry. Protandry DichogamProtogamyStamens mature before styles. As in strawberry.ProtandryStyles mature before stamens. Compound family