This presentation contains a lots of information about the contribution of the scientists who works in the field of reproductive biology of angiosperms.

2. REPRODUCTING OF PROCESS IN ANGIOSPERMS
 Flower is the main reproductive organ of a plant.
 Flower contains Stamen(male reproductive part) and Carpel(female reproductive part)
 Stamen is made up of Anther and Filament. Anther produces pollen grains which is contains the male gametes or
sperms.
 Carpel is made up of Stigma, Style and Ovary. Inside the ovary ovules are present that contains the female gamete
or egg cells.

3.  Pollen grains brings to the stigma of female reproductive part from anther. The
process of transfer of pollen grains to stigma of carpel from anther, known as
Pollination .
 Then a pollen tube is formed from the pollen grains to the ovule through style.
Male gametes reaches to the ovary through this tube. In the ovary pre-present
female gametes fuses with the male gametes and forms a Zygote.
 After that the zygote cell developed an embryo. Ovule develops a tuff coat over
it and changes into seed. Seed turns into seedling and seedling develops a new
plant.

4. SCIENTISTS , WORKED TO DISCOVER THE
PROCESS OF REPRODUCTION IN
ANGIOSPERMS
Giovanni Battista Amici
Wilhelm Hofmeister
Eduard Strasburger
Sergius Nawaschin
Panchanan Maheswari
Brij Mohan Johri
William A Jenson
Jack Heslop- Harrison

5. GIOVANNI BATTISTAAMICI
 ABOUT:
 Giovanni Battista Amici, a Italian Astronomer,
Microscopist and Botanist(25 March 1786 - 10 April 1863)
 CONTRIBUTION:
 Discovered the pollen tube in Protulaca
oleracea
 Observed a hair like structure over the stigma
having a granules under it.
 He kept it under observation for three hour and
saw that the pollen grain split and forms a tube
that entered the tissue of stigma.
G. B. Amici
(1786-1863)

6.  In 1830 he repeating his observation, after that, he confirmed that
the pollen tube after emerging from the pollen grain grew bit by bit
and finally, came in contact with the ovule.
 G.B,AMICI

7. WELHELM HOFMEISTER
 ABOUT:
 Weilhelm Hofmeister, a German biologist, botanist
(18 May 1824 - 12 January 1877)
 CONTRIBUTION:
 Discovering the alternation of generation in plants
 Traced the formation of embryo from the egg
right up to its maturity in the seed(1849)…….
Wilhelm Hofmeister
(1824-1877)

8. Wilhelm Hofmeister

9. EDUARD STRASBURGER
 ABOUT:
 Eduard Adolf Strasburger, a German professor and one of the
most famous botanist of the 19th century
(1 February 1844 - 18 May 1912)
 CONTRIBUTION:
 Greatest contribution : observed the actual
fusion of the male gamete with the female
gamete (the process called syngamy) in
Monotropa and other plants…..
EDUARD ADLOF
STRASBURGER
(1844-1912)

10. EDUARD ADLOF
STRASBURGER

11. SERGIUS NAWASCHIN
 ABOUT:
 Sergius Gavrilovich Nawaschin was a
Russian biologist and botanist.
(14 December 1857 – 10 December 1930)
 CONTRIBUTION:
 One of his greatest discovery is the
double fertilization (mainly the triple fusion)
in angiosperms in 1898.
 He described the whole syngamy and
the triple fusion process through Fritillaria
Sergius
Gavrilovich Nawaschin
(1857-1930)

12. Sergius
Gavrilovich Nawaschin

13. PANCHANAN MAHESWARI
 ABOUT:
• Indian botanist(9 November 1904 – 18 May 1966),
Founder of “ Globally important center of
research in embryology and tissue culture” in Delhi
University. He taught Botany at Delhi University.
He also founded the “International Society of Plant
Morphologists”
• Wrote world famous book is “An introduction to the
embryology of angiosperms”(1950)
• Known as “Father of Indian Embryology”
PANCHANAN
MAHESWARI
(1904-1966)

14.  CONTRIBUTION:
• Chiefly noted for test-tube fertilization in angiosperms. This invention has
allowed the creation of new hybrid plants that could not previously be
crossbred naturally
PANCHANAN
MAHESWARI

15. BRIJ MOHAN JOHRI
 ABOUT:
o Indian Botanist, Professor and Author(1909 – 1 January 2003).
His areas of specialization were developmental,
comparative, phylogenetic and experimental
studies of angiosperms.
 CONTRIBUTION:
o Observed the largest synergid cell and a 3 nucleateantipodal branched
haustoria in Quinchamalium of Santalaceae
o Apply embryology data to the study of taxonomy
BRIJ MOHAN
JOHRI
(1909-2003)

16. WILLIAM AUGUST JENSEN
 ABOUT:
o Professor of botany of Ohio State University, Columbus
 CONTRIBUTION:
o A pollen tube discharges its contents in one of the synergids from where
one of the sperms migrates to the egg and the other to the polar nuclei.
(Arabidopsis thaliana)
WILLIAM
AUGUST
JENSEN
(1927-2014)

17. JACK HESLOP-HARRISON
 British botanist, He was not only a botanist but also a soldier in
world war II. (10 February 1920 – 7 May 1998)
 CONTRIBUTION:
 Understand the structure and developmemnt
of pollen wall and involvement of pollen
wall materials in pollen-pistil interaction
following pollination. JACKHESLOP-HARRISON
(1920-1998)

18. JACK HESLOP-HARRISON