embryology of angiosperms

460 Pages·2013·53.01 MB·English

AN INTRODUCTION
TO THE
EMBRYOLOGY
OF ANGIOSPERMS
BY
P. MARE RWARI
Professor of Botany, University of Delhi
Delhi, India
.
Ll~RARY
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INSTITUTE OF HORTICULTURAL RESEAROH
(HESSARGHATTA.) BANGAl.ORE.
McGRAW-HILL BOOK COMPANY, INC.
NEW YORK TORONTO LONDON
1950
AN INTRODUCTION
TO THE
EMBRYOLOGY OF ANGIOSPERMS
McGRAW-HILL PUBLICATIONS ]l':
THE BOTANICAL SCIENCES
Edmund W. Sinnott, Consulting Editor
ARNOLD An Introduction to Paleobotany
CURTIS AND CLARK An Introduction to Plant Physiology
EAMES Morphology of the Angiosperms
EAMES Morphology of Vascular Plants: Lowel' Croups
EAMES AND MACDANlELS An Introduction to Plant Anatomy
HAUPT An Introduction to Botany
HAUPT Laboratory Manual of Elementary Botany
HAUPT Plant Morphology
HILL Economic Botany
HILL, OVEJUIOLTS, POPP, AND GROVE Botany
JOHANSEN Plant Microtechnique
KRAMER Plant and Soil Water Relationships
KRAMER AND KOZLOwSKI Physiology of Trees
LILLY AND DA~TT Physiology of the Fungi
MAIi.ESHW HI -An Intr~on to the Embryology of the Angiosperms
MILLER Plant Physiolqgy .
POOL Flowers and F1o~ring Plants
SHARP Fundamentals of Cytology' .
SYNNOTT Plal)t Morphogenesis ; .
SIN OTT, DUNN, AND DOBZHANS. ..'.Y . Prirtciples of Genetics
SINNOTT AND 'WILSON Botany: Prinoiples' and Problems
SMITH CryptogamiC Botany
Vol. 1. Algae and Fungi
Vol. II. Bryophytes and Pteridophytes
SMITH The Fresh-water Algae of the United States
SWINGLE Textbook of Systematic Botany
WEAVER AND CLEMENTS Plant Ecology
There are also the related series of McGraw-Hill Publications in the Zoological
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AN INTRODUCTION TO TiIE EMBRYOLOGY OF ANGlOSPERMS
Copyright, 1950, by the McGro.w-lIill Book Compo.ny, Inc. Printed in the
United Slo.lell of America. All rights reserved. This book, or parts thereof,
may not bo reproduced in any form without permission of tho publishers.
VII
PREFACE
In the e day of inten e activity, when hundred of papers are
being publi hed in every field of botany in a teadily incr a jng
number of periodical and in a multitude of langua ,no apolo-ry
i ne d d for an attempt to ummarize the exi ting state of our
knowled "e in an branch of the ubject and to point out the futW'e
po ibilities in it. ince the pUblication of Coulter and Chamber
lain' "Morphology of Angio perm " in 1903, no comprehensive
account of this aspect of botany has appeared in the English lan
guage.
The original impetus for writing this work 1'e ulted from a curse
of lecture which I gave on the subject in 1930 when I wa teaching
at the Agra College. everal colleague and pupil then ugge ted
that I hould produce a book on the embryology of angiosperms.
Tills sugge tion wa repeated by Profe or . Tischler of the Uni
versity of Kiel, whom I visited in 1936. T aching and adminis
trative duties and other difficultie made it iropo ible for me to
carryon this work in India at the 'peed I bould have liked. oon
after the war was over in 1945, ther fore, I took th manuscript to
the United States in order to 1'evi c it and put it in shape for publi
cation.
In a strict sense, embryolorry is confined to a study of the embryo,
but most botanists also include under it the e;.ents which lead on
to fertilization. I am in a reement with thi wider comprehen 'ion
of the subject and have therefore included in this volume not only
an account of the embryo and endosperm, but al 0 an 'account of
the development of the male and female gametophytcs and fertiliza
tion. To emphasize the recent trend of 1'e earch in the subject,
two chapters of a general nature have been added, one dealing with
embryology in relation to taxonomy, and the other with experi
mental embryolo 'y. In the former, an attempt has be n made to
indicate the pos ibilities of the embryological method in th olu
tion of problems of systematic botany. In the latter, emphasiR
ba been placed on the contact between embryology, cyt,ology,
jtenetics, and olant physiology.
v
vi PREFACE
In compiling my materials I must acknowledge the immense help
which I received from the writings of the late Profes or K. Schnarf,
whom I came to know rather intimately during my stay in Vienna
in 1936. Without the existence of his books, entitled "Embryologie
der Angiospermen" (1929), "Vergleichende Embryologie der Angio
spermen" (1931), and "Vergleichende Zytologie des Geschlecht-
a,pparates des Kormophyten" (1941), my task would have been
appreciably greater. Mention must also be made of the numerou
and very valuable publications of Professor E. C. R. Souege (Pari),
Professor K. V. O. Dahlgren (Uppsala), Dr. J. Mauritzon (Motala),
Dr. F. Fagerlind (Stockholm), Dr. A. Gustafsson (Svalof), and
Dr. H. Stenar (Sodertalje), upon which I drew rather freely. Pro
fessor Dahlgren, Dr. Gustafsson, and Dr. Stenar also favored me
with their advice and criticisms whenever I applied to them for
help. In addition, a host of teachers and students in the United
States gave me every po sible encouragement in the work. To
record my gratitude to all of them in any complete fashion would
fill several pages. I therefore content myself with naming a few
who took special interest in the project. To Professors R. H.
Wetmore and 1. W. Bailey I am heavily indebted for the free use of
their facilities and their assistance in other ways during my several
months' stay at Hat'vard. Profe SOl' A. F. Blfl.keslee and Mary E.
Sanders, Smith College, Northampton; Professor E. W. Sinnott,
Yale University; Profes ors A. J. Eames and L. W. Sharp, Cornell
University; Drs. D. C. Cooper, R. A. Brink, and C. L. Huskins,
University of Wisconsin; Dr. Th. Just, University of Notre Dame,
now at the Field Museum of Natural History, Chicago; Professor
J. T. Buchholz, University of Illinois; Profes or A. S. Fo tel', Pro
fessor G. L. Stebbins, Mrs. M. S. Cave, Drs. L. Constance, Katherine
Esau, and C. M. Rick, all of the University of California; Pro
fessor G. M. mith, Stanford University; Dr. D. A. Johan en, Po
mona, and Professor A. W. Haupt, University of California at
Los Angeles, gave me the benefit of their suggestions and criti
cisms. Last but not least, my colleagues and pupils, Dr. B. M.
Johl'i, Reayat Kahn, . Narayanaswami, and J. . Agrawal gave
me their fullest cooperation in the preparation of the bibliography
and revision of the proofs.
Only a few of the illustrations are original, most of them having
been borrowed from the works of other authors. Considerabl~
care has been exercised, however, in their selection not only that th~
vii
text may be made as clear as possible but also that the tudent may
acquire some familiarity with the names and contributions of the
better known embrvologists, both past and present. While most
of the copying and redrawing was done by me per onally, I am
glad to acknowledge the very able assistance I received from a few
friends. Figures 36, 6 , 92, and 214 were drawn by Mrs. J. A.
Adams of Poughkeepsie, N. Y., daughter of my former teacher,
the late Dr. Winfield Dudgeon of Allahabad; Mi s C. Pratt,
Harvard University, drew Figures 24, 41, 59, 65, 74, 9, 104, 11 ,
121, and 167; Dr. B. G. L. wamy, Bangalore, dr w Figures 19,
145, 149, 150, 153, and 163; Mrs. M. . Cave, University of Cali
fornia, drew Figure 14; Mis C. G. Na t, Wayne University, drew
Figure 111; and my former research a si tant, Ashraful Haque,
University of Dacca, drew Figures 21, 43, 47, 54, 60, 61, 2, 5,
91, 147, 148, 152, 154,157, 15 , 159, 161, 162, 164,165, 170, 172,
173, 175, 191, and 216. To all these I wi h to tender my mo t
grateful thanks for the willingn ss with which they cooper at d
with mc.
A word about the citation of literature. No attempt has been
made to give a complete list of all that has been pullished on
angiosperm embryology, as this would make the volume too cum
bersome, but it is hoped that the references which have been cited
will facilitate the task of the tudent who wishes to acquire fuller
information.
In a work of this nature it is unavoidable that there should be
some errors of judgment and also oversights and omissions. I
should appreciate the suggestions and criticism of those who u e
the book.
P. MAHESHWA RI
UNIVERSITY OF DELHI, INDIA
July, 1950
CONTENTS
PREFACE... . ....... .. ... . ..... ... ....... ...... ... ... .. ...... ........ V
1. HISTORICA.L SKETCH .................... ........••.. ...............
Di covery of Pollen Tube chleiden's Theory of Origin of Embryo
Di 'covery of True Relation betv.·een Pollen Tube a.nd Embl'yo- Di. covery
of exual Fusion in LOlI'er Plants- Discovery of Nature and Development
of Male and Female Gametophytes-Embr}'o- Discovery of yngamy
Chalazogamy- Dou ble Fertilization-Parthenogenesis-Twentieth Cen
tury-References.
,/ 2. THE MICROSPORANGIUM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Wall Layer - Sporogenous Ti sue- Cytomixis-Cytokinesis- Microspol'e
Tetrad- References.
3. THE 1EGASPORANGIUM........ ...... ... ... .. .......... ............ 54
Integuments-Micropyl N ucellus-Integumentary Tapetum- Hypo
stase-Epistase-Va cular upply of Ovule-Al'chesporium- M ga poro
genesis-Functioning Mega pore- Failure of Wall Formation during
Meiosis-Reference.
4. THE FEMALE GAMETOPHYTE. . . . . . .. . .. . ... .. . .. . ... .. . .. . .. . .. . .. . 4
Monosporic embryo sacs-Polygonum Type-Oenothera Type-Bisporic
embryo sacs- Allium Type- Tetrasporic embryo sacs- Peperomia Type
Penaea Type-Drusa Type- Fritillaria. Type-Plumbagella Type- Adoxa
Type- Plumbago Type- Aberrant and unclassified tIJpes-IJimnanthes
dov{/lasii- BalsamUa vul(Jaris- hrysanthem'um cinerariaefolium- Or
ganization of mature embryo sac- Egg Apparatus-Antipodal e1l8-
Polar Nuclei- Embryo Sacs with Disturbed Polarity- Food Reserves in
the Embryo ac- Embryo Sac Haustoria- References.
, 5. THE MALE GAMETOPHYTE .... ... ............ ................ , ..... 154
Micro pore-Formation of Vegetative and Generative Cells- Division of
Generative Cell- Male" ells" or "Nuclei"- Vegetative Nucleus- De
velopment of Pollen in Cyperaceae-Embryo-sac-like Pollen Graills
References.
6. FERTILIZATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 181
Germination of Pollen- Course of Pollen Tube-Entry of Pollen Tube
into Embryo ac-Rate of Growth of Pollen Tube- Gametic Fu ion
Multiple Fusions and Polyspermy-8ingle Fertilization- Persistence and
Possible Haustorial Function of Pollen Tube-X-bodies-RefereDces.
7. THE ENDOSPERM.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 221
Types of Endo perm Formation- Free Nuclear Endosperm- Cellular
Endosperm-Helobial Endosperm- Relationships between Different
Types of Endosperm- Histology of EndoBperm- Xenia- Mosaic Endo
sperm-References.
ix
CONTENTS
8. THE EMBRYO.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 268
Dicotyledons-Crucifer Type-Asterad Type-Solanad Type-Cheno
podlad Type-Caryophyllad Type-Monocotyiedons-Modifications of
sU8pensor-Unclassifted and abnormal embryos-Unorganized and reduced
embryos- References.
9. ApOMIXIS ............................ .. ................ .. .... .... 313
Nonrecurrent apomixis-Recurrent apomixis-Generative Apospory-So
matie Apospory-Unclassified Cases-Qrganization of Aposporic Embryo
Sacs-Development of Embryo in Aposporic Embryo Sacs-Adventive
embryony-References.
10. POLYEMBRYONY . ......... , . " ....... '" ... '" ......... " .. ' .... '" 343
Cleavage Polyembryony-Origin of Embryos from Cells of Embryo Sac
Other than Egg- Embryos Arising from Cells Outside Embryo Sac
Embryos Originating from Other Embryo Sa.cs in Ovule-A Few Special
Cases- Twins and Triplets-Conclusion-References.
11. EMBRYOLOGY IN RELATION '1'0 TAXONOMY ........................... 357
Empetraeeae- Lennoa.eeae-Cactaceae-Garryaceae-Onagraceae-Calli
trichaceae-Liliaceae-allioideae-Liliaceae-asphodeloideae-Liliaceae-lili
oideae-References.
12. EXPERIMENTAL EMBRYOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 375
Control of Fertilization-Embryo Culture-Induced Parthenogenesis
Production of Adventive Embryos-Induced Parthenocarpy-Conclu
sion-References.
13. THJJlORE'flCAL CONCLUSIONS ......... ... ......... ............. .... " 411
Male Gametopbyte- Female Gametophyte-Fertilization-Endosperm
Embryo-References.
NAME INDEX ...... .............. .................... ................. 433
SUlIJECT AND PLANT INDEX .....•. •. ••...... ...•.•••........•.•..... .. 441
CHAPTER 1
HISTORICAL SKETCH
In tracing the history of a branch of natural science it is customary
to go back to the days of Aristotle. The greater part of his technical
writings is unfortunately lost to us, but it seems fairly certain that
he did not recognize the presence of ex in plants. He believed
instead that the male and female principle were so blended that
they generated of their own accord and the offspring arose from the
superfluous food in the plant.
Aristotle bequeathed his library and collections to his favorite
pupil Theophrastus. In his "Enquiry into Plants," written in the
third century B.C., the latter referred to the pollination of the date
palm, presumably on the basis of the account of Herodotus, who
had traveled in the East in the fifth century B.C. The Arabs and
As yrian , Herodotus found, used to have a special ceremony at a
certain time of the year, in which a man climbed up a male tree,
brought down the inflorescence, and handed it over to the high
priest, who touched the female inflorescences with it, in order to
ensure a good supply of dates.
Approximately three hundred years after Tbeophrastus, Pliny
wrote an encyclopedia of natural history in which he mentioned the
male palm with its erect leaves as having somewhat of a military
bearing, while the females with their softer foliage and feminine ways
bent toward it, to save themselves as it were from the curse of
virginity or widowhood. However, Pliny did not make any ob
servations of his own. His writings and ideas were based on otber
people's reports and on the literature on tbe subject that existed in
those days.
Mter this the problem of sexuality in plants seems to have been
laid aside and forgotten for hundreds of years. Indeed, many scien
tists of the fifteenth and sixteenth centuries totally denied the
occurrence of sex in plants and regarded even the mention of it as
inappropriate and obscene. Some thought the stamens to be ex
cretory organs and the pollen to be a waste produet.