全 文 ：·Short Communication·
A New Type of Embryo Sac in Cardiopteris and
Its Systematic Implication
KONG Dong_Rui , PENG Hua＊ , LIANG Han_Xing
(Kunming Institute of Botany , the Chinese Academy of Sciences , Kunming 650204 , China)
Key words:　Cardiopteris;new type of embryo sac;systematic implication
　　Cardiopteris Wall.ex Royle (1836)(=Periptery-
gium Hassk.), comprising three species:C.platy-
carpa , C.quinqueloba , C.moluccana , is distributed
from southeast Asia to northeast Australia[ 1] .Its system-
atic position and relationship are controversial.The genus
has been assigned to Olacaceae
[ 2]
or Icacinaceae
[ 1] .
Blume conceived it as a type of monogeneric family[ 3] ,
and now most taxonomists place it in the order of Celas-
trales as a distinct family with affinities to Icaci-
naceae[ 4-6] .However , Cronquist ever thought that the
genus was insufficiently studied and might prove to be
misplaced in the Celastrales[ 4] .Recently[ 7] , Takhtajan
considered it as an independent order , while it is in an
uncertain position based on morphological or molecular
data[ 8] .It is clear that the systematic position of Car-
diopteris can not be determined until it has been more
carefully studied.Comparative embryology has been an
important approach in revealing the relationship of taxa at
familiar or higher levels[ 9] .The embryological investiga-
tions reported in this paper were carried out to provide
more information on Cardiopteris classification.Its embry-
ological features were thoroughly observed:Cardiopteris
has a new type of embryo sac , whose egg apparatus sits in
the chalazal end.
1　Materials and Methods
Buds , flowers and fruits of Cardiopteris platycarpa
Gagnep.at different developmental stages were collected
from Malipo County , Yunnan Province , China , and were
fixed in the FAA(formalin , acetic acid , 50%alcohol , 4∶6∶90)from August to October 2000.The voucher speci-
men(H.Peng 3501)was deposited in KUN.Flowers
and fruits were dehydrated through a t_butyl alcohol se-
ries , and then embedded in paraplast.Serial sections cut
7-10 μm in thickness were stained with Heidenhain s
hematoxylin and Orange_G.Observation and photographs
were performed using Olympus BX52.
2　Results
The ovary is superior , bicarpellary , syncarpous and
unilocular with two ategminous , orthotropous ovules
pendulous from the summit of the ovary (Fig.1).The
ovule is tenuinucellate (Fig.5).Unlike the development
of embryo sac of Polygonum type , in the mature embryo
sac , three nuclei in the chalazal end constitute the egg
apparatus (Figs.2 , 4 , 6 , 7), while three in the mi-
cropylar end are antipodals(Figs.3 , 4 , 8 , 9), and two
other nuclei act as polar nuclei(Figs.2 , 4 , 6 , 10).The
tips of the synergids are prolonged into a “beak” (Fig.
6).The zygote and the embryo also lie in the chalazal
end(Figs.11 , 12).The zygote has a large nucleus and
the wall is conspicuous(Fig.11).
3　Discussion
It has never been reported that the egg apparatus sits
in the chalazal end in all angiosperms whose embryology
has been investigated.The egg apparatus lies in the mi-
cropylar end in thirteen types of embryo sac without ex-
ception[ 10] .Therefore , this type of embryo sac , whose
egg apparatus stands in the chalazal end , should be con-
sidered as a new type.Based on such an autapomorphy ,
it can be concluded that Cardiopteris is a highly isolated
taxon.Takhtajan s taxonomic treatment[ 7] is supported by
such embryological data.In a subsequent paper we will
discuss its systematic position and relationship , in con-
junction with its other features , especially with embry-
ological ones.
Acknowledgment:We thank Prof.WU Zheng_Yi for his
care of this project , Dr.LI De_Zhu for improving the
English language presentation of the paper , Mr.GONG
Xun for cooperation in fieldwork , Ms LI Lu and Ms PAN
Yue_Zhi for help and cooperation in the experiment.
References:
[ 1] 　Chuang H.Icacinacea.Fang W_P.Flora Reipublicae Poru-
lasis Sinicae.Beijing:Science Press , 1981.46:177-
180.(in Chinese)
[ 2] 　Dahlgren R.A system of classification of angiosperms to be
used to demonstrate the distribution of characters.Bot No-
tiser , 1975 , 128:189-147.[ 3] 　Sleumer H O.Cardiopteridaceae.van Steenis C G G J.
Flora Malasiana.Groningen:Wolters_Noordhoff Publishing ,
1971.93-96.
Received:2001-08-28　Accepted:2001-11-20
Supported by the Major Project on Important Taxa of Border between East Asia and Tropical Asia , the Chinese Academy of Sciences(STZ98_1_03 and KZ951_A1_
104_03).
＊Author for correspondence.Fax:++86_871_5150227;Emai l:.
植　物　学　报　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　

Acta Botanica Sinica　2002 , 44(4):496-498
Figs.1-12.　The chalazal end is at the top in all twelve photos.1.Two ategmic orthotropous ovules pending from the summit of the ovary.
2-4.Serial sections.Mature embryo sac , the sac is irregular linear , including egg apparatus , three antipodals and two polar nuclei.5.The
tenuinucellate ovule.6.Part amplification of the chalazal end of Fig.2 , showing two synergids and a polar nucleate.7.Part amplification of
the chalazal end of Fig.4 , showing one egg cell.8 , 9.Part amplification of the micropylar end of Figs.3 , 4 , showing three antipodals.10.
Part amplification of Fig.4 , showing a polar nucleus.11.Zygote in the chalazal end.12.Proembryo in the chalazal end.
Abbreviations:an , antipodal;eg , egg;sy , synergids;pn , polar nucleus;pr, proembryo;zy , zygote.Scale bars equal 100 μm in Figs.1-
4 and 12;30 μm in Fig.11 , and 20 μm in Figs.5-10.
[ 4 ] 　Cronquist A.An Integrated Sy stem of Classification of Flow-
ering Plants.New York:Columbia University Press , 1981.
723-724.
[ 5 ] 　Mabberley D J.A Portable Dictionary of the Vascular Plant.
Cambridge:Cambridge University Press , 1997.[ 6 ] 　Battacharyyka B , Johri B M.Flowering Plants Taxonomy
and Phylogeny.Narosa:Springer_Verlag , 1998.
[ 7 ] 　Takhtajan A L.Diversity and Classification of Flowering
Plants.New York:Columbia University Press , 1997.352
-353.[ 8] 　The Angiosperm Phylogenetic Group (APG).An ordinal
classification for the families of flowering plants.Ann Mis-
souri Bot Gard , 1998 , 85:531-553.[ 9] 　Herr J M.Embryology and Taxonomy.Johri B M.Embry-
ology of Angiosperms.Berlin:Springer-Verlag , 1984.[ 10] 　Johri J M , Ambegaokar K B , Srivastava P S.Comparative
embryology of Angiosperms. Berlin: Springer_Verlag ,
1992.29-41.
KONG Dong_Rui et al:A New Type of Embryo Sac in Cardiopteris and Its Systematic Implication 497　
心翼果一新的胚囊类型及其系统学意义
孔冬瑞　彭　华＊　梁汉兴
(中国科学院昆明植物研究所 , 昆明　650204)
摘要:　报道心翼果属(Cardiopteris Wall.ex Royle)一种新的胚囊类型:胚珠无珠被 、直生 、薄珠心。成熟胚囊中 , 卵
器位于合点端 ,反足细胞位于珠孔端。这样的胚囊在所有进行过胚胎学研究的被子植物中系首次发现。合子和胚
胎也位于合点端。心翼果属的这一新特征无疑是特异性的 ,据此可认为单型科心翼果科在一定程度上是十分孤立
的。
关键词:　心翼果属;胚囊新类型;系统学意义
中图分类号:Q944.4　　　文献标识码:A　　　文章编号:0577-7496(2002)04-0496-03
收稿日期:2001-08-28　接收日期:2001-11-20
基金项目:中国科学院重点项目:东亚南部界面被子植物关键类群的系统学与地理学研究。
＊通讯作者。Fax:++86_871_5150227;E-mai l:.
(责任编辑:李长复)
498　 植物学报　Acta Botanica Sinica　Vol.44　No.4　2002