D
Journal of Life Sciences 8 (2014) 946-954
doi: 10.17265/1934-7391/2014.12.004
DAVID
PUBLISHING
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.)
Fruit in Seed Development
Hermine Bille Ngalle1, Joseph Martin Bell1, Georges Franck Ngando-Ebongue2, Hernild Eman-Evina1, Godswill
Ntsefong Ntsomboh2 and Armand Nsimi-Mva3
1. Department of Plant Biology, Faculty of Science, University of Yaoundé I, Yaoundé, P.O. Box 812, Cameroon
2. Specialized Oil Palm Research Centre (CEREPAH of La Dibamba), IRAD, Douala, P.O. 243, Cameroon
3. Ekona Regional Research Centre, IRAD, Buéa, P.O. Box 25, Cameroon
Received: November 14, 2014 / Accepted: December 2, 2014 / Published: December 30, 2014.
Abstract: The place of the oil palm, Elaeis guineensis Jacq., in the market for fats of vegetable commodities makes it a strategic
plant which requires continuous improvement. In this context, it seems appropriate to better describe the effects of the Sh gene in the
developing fruit. This study aims to set a benchmark for the development of the seed in the natural palm (Elaeis guineensis var. dura).
Thus the growth and development of the two major seed tissues were monitored every two weeks from pollination to maturity of the
fruit. The results show that the endosperm is still liquid six weeks after pollination. It then begins an accelerated development which
leads it, 11 weeks later, to completely fill the seed cavity, with an average mass of 0.81 g. This mass remains stable until the maturity
of the fruit. The embryo is only visible when the endosperm is gelatinous, around 70 DPP (days post-pollination). It then has an
average length of 1.00 mm. At 126 DPP, the embryo has finished growing and measures 2.82 mm on average. This length also
remains stable until 168 DPP (3.04 mm). In perspective, a detailed follow-up of the development of the zygote from the pollination to
100 DPP is proposed. In parallel, the analysis of the chemical composition of the endosperm between 100 DPP and 168 DPP is
necessary. These two complementary studies will allow to better specifying the benchmark of seed development in Elaeis guineensis
var. dura.
Key words: Elaeis guineensis Jacq., embryo, endosperm, seed, development.
1. Introduction
Since 2006, palm oil, extracted from the mesocarp of
the fruit of the oil palm (Elaeis guineensis Jacq.),
became the first source of vegetable fat on the world
market [1]. With a world production of 57.3 million
tons in 2013 [2], this oil also ranks first in terms of
production. Palm oil reaches this performance thanks
to its exceptional yield, with world average around four
tons of palm oil per hectare [3]. This productivity of the
oil palm is much greater than that of all oilseed crops. It
is ten times higher than that of soybean [3-5]. With a
production of 6.8 million tons in 2013 [2], palm kernel
oil extracted from the seed also holds an important
Corresponding author: Joseph Martin Bell, Ph.D.,
associate professor, research fields: genetics and plant breeding.
E-mail: [email protected].
place in the consumption of fats of vegetable origin. Oil
palm appears as a strategic plant for the economy of
numerous producing countries.
Breeding programs and genetic improvement of this
species are primarily focused on the development of
planting material more efficient in terms of production
of palm oil and kernels [6]. However, the history of
selection in this plant is of recent [4, 7-10]. It
consisted up to here in indirectly valuing a natural
mutation that occurred on the shell (Sh) gene, which
specifically controls the thickness of the endocarp in
this species [11, 12]. At this locus, the wild palm dura
having the genotype Sh+Sh+ with thick endocarp and
large seed is distinguished from the mutated palm
named pisifera having the genotype Sh-Sh- without
endocarp and with a tiny seed, and the hybrid palm
947
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
tenera descended from the cross [♀ dura × ♂ pisifera],
having the genotype Sh+Sh- with thin endocarp and
normal seed [13, 14].
The Sh gene seems to have a direct impact on the
endocarp and an indirect effect on the survival of the
seed and thus on the female infertility in E. guineensis
[6, 15]. This pleiotropy of the Sh gene has not yet
been clarified. A very interesting orientation and a
source of significant progress would be to develop a
pisifera planting material thus producing fruits
without endocarp, but in which the indirect effect of
the Sh gene mentioned above would be reduced or
eliminated. In other words, it would be a matter to
identifying candidate genes for the restoration of
female fertility in E. guineensis Jacq. var. pisifera.
To better analyse the pleiotropy of this gene, it is
necessary to have a precise benchmark for the
development of oil palm fruit at a time when the
mutated allele is not present. A recent study has
already described the development of the pericarp of
the fruit of the oil palm [16]. The general objective of
the present work is to describe the development of the
seed of E. guineensis Jacq. var. dura. Specifically, the
study assesses changes in the seed lodge; determines
the deadlines of appearance of the endosperm and the
embryo, as well as the pace of development of these
two tissues, from pollination to the fruit maturity.
2. Materials and Methods
The plant material is freely obtained from the
CEREPAH (Specialized Oil Palm Research Centre) of
La Dibamba, one of the stations of the IRAD (Institute
of Agricultural Research for Development) in
Cameroon. It consists of fruits collected from maturing
oil palm bunches.
Five assisted pollinations were made between dura
(female parent) and pisifera genitors (Table 1).
Fruits were sampled on bunches, every two weeks
from the first DPP (day post-pollination) to the
maturity of bunches. Maturity is substantiated by the
natural detachment of the first fruits. At each stage of
Table 1 Genitors used and controlled pollinations made at
CEREPAH (Specialized Oil Palm Research Centre).
Date of pollination
♀ Genitors
A98D 22 14
A98D 23 21
09/26/2011
B91D 29 07
C19D 14 08
Matings
♂ Genitors
LD2272 P
×
×
×
×
×
LD2272 P
LD1568 P
LD2272 P
LD2272 P
C19D 24 17
D: Elaeis guineensis Jacq. var. dura; P: Elaeis guineensis Jacq.
var. pisifera.
development, 30 fruits were taken from the whole
bunch, that is 150 fruits for five bunches.
Fruits sampled underwent longitudinal or transverse
sections, which were observed with the naked eye
and/or by means of a EUROMAX optical microscope
with a micrometre. These observations were essentially
aimed at assessing the shape of the lodge of the seed,
determining the time of onset of the endosperm and
embryo. Different measurements on these tissues can
track, from pollination fruit maturity, the evolution of
the:
 equatorial diameter of the lodge of the seed,
measured microscopically for the early stages of fruit
development (0-42 DPP). In later stages, this parameter
is measured using a ruler;
 consistency of the endosperm, appreciated with
the naked eye and the touch;
 mass of the endosperm. For young phases of fruit
development (0-70 DPP), this parameter is estimated
by the formula Men = Mwf - Mhf, where Men, Mwf and Mhf
represent respectively the masses of the endosperm, the
whole fruit (with the seed) and the hollowed fruit (fruit
freed of the seed). At the advanced stages, this
parameter was measured using a precision balance 0.1
mg brand RADWAG (series AS/X), minimum and
maximum capacity estimated at 10 mg and 220 g
respectively;
 length of the embryo, measured microscopically
for young stages of development (0-98 DPP) and with a
graduated ruler for the advanced stages (over 112
DPP).
948
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
from the 42nd DPP shows that of the 1,350 fruits tested,
997 (74%) each contained a lodge, 293 (22%) with two
lodges each and 60 (4%) with more than two lodges
(three or four).
For each stage, the mean and standard deviations of
the parameters were calculated. The curves showing
the evolution of these parameters over time are built
using the Microsoft Office Excel 2010 software. A
digital camera HP PhotoSmart M425 allowed setting
the observed structures.
3.2 Evolution of Endosperm
The endosperm is present from 17 DPP. It is in liquid
form until 42 DPP. Between 42 DPP and 70 DPP, it
becomes gelatinous (Fig. 2a). From 84 DPP, it is
cartilaginous (Fig. 2b). Beyond 126 DPP, it has already
acquired the final solid consistency (Fig. 2c) of a
mature endosperm (Fig. 2d).
3. Results
3.1 Evolution of the Seed Lodge
During the early stages of development (0-17 DPP),
the cutting of the fruit generally presents three small
cavities, arranged in the form of a clover (Fig. 1a).
Gradually, as the fruit grows, the number of cavities
tends to decrease on average towards two lodges (Fig.
1b). And from the 42nd DPP, the fruit usually has a
single cavity (Fig. 1c), supposed to contain the unique
seed (Fig. 1d). However, some fruits reach maturity
with two or more seeds (Figs. 1e and 1f).
Evaluation of fruits with regard to existing lodges
(a)
3.3 Evolution of the Embryo
In the mature fruit, it is located in the linear
“extension” of the germ pore (Fig. 3a) and its final
average size (at 168 DPP) is 3.04 ± 0.15 mm (Fig. 3b).
Overall, the study shows that the growth in mass of
the endosperm really starts after 28 DPP, as it is 0.09
(b)
(c)
(d)
(e)
(f)
Fig. 1 Sections of fruits of Elaeis guineensis var. dura. (a): fruit with three cavities (17 DPP); (b): fruit with two cavities (28
DPP); (c): fruit with one cavity (42 DPP); (d): 1-seeded fruit (168 DPP); (e): 2-seeded fruit (168 DPP); (f): 3-seeded fruit (168
DPP); DPP: days post-pollination; arrows indicate the location of cavities (a, b and c) or seeds (d, e and f).
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
(a)
949
(b)
(c)
(d)
Fig. 2 Evolution of the endosperm consistency of Elaeis guineensis var. dura. (a): gelatinous (70 DPP); (b): cartilaginous
(112 DPP); (c): solid (154 DPP); (d): solid (168 DPP); DPP: days post-pollination.
Gp
Em
En
(a)
(b)
Fig. 3 Embryos of Elaeis guineensis var. dura. (a): location of the embryo within the seed; (b): mature embryo; Gp: germ
pore; Em: embryo; En: endosperm.
± 0.00 g at 42 DPP. This tissue of the seed grows
steadily and reaches its maximum average mass (0.81
± 0.04 g) at 126 DPP. The embryo, which is noticeable
on the 56th DPP begins its growth from the 70th DPP
and almost achieves its maximum average length
(2.82 ± 0.14 mm) at 126th JPP. It is also at this time
that the maximum diameter of the seed lodge is
reached, dressing peaks from 1.80 ± 0.07 mm (28 DPP)
to 10.07 ± 0.60 mm (126 DPP). Fig. 4 shows average
parameters of seed’s growth, including the diameter of
the seed lodge, the length of the embryo and the mass
of the endosperm.
950
Fig. 4
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
Average parameters for growth of the seed of E. guineensis var. dura.
The early seed development of E. guineensis var.
dura is characterized by the stabilization of the number
of lodges of the seed. Indeed, the setting of this
parameter at 42 DPP allows the endosperm to pass
from a liquid to a gelatinous state. And from 70 DPP,
the solidification of the endosperm engages in the
development of the embryo, whose growth seems to
require prior jellification of the endosperm. At 126
DPP, both seed tissues reach their maximum growth.
During the last six weeks of fruit development
(126-168 DPP), these two tissues do not grow
substantially but certainly enter their maturation stage.
4. Discussion
The first manifestation of the development of the
seed in E. guineensis var. dura is the stabilization of
the number of lodges that must shelter one or several
future seeds of the mature fruit. Among examined
fruits, 26% contain at least two seeds. This supports
previous data that set the frequency of such oil palm
fruits between 20% and 25% [15, 17, 18]. Hojiblanca,
Arbequina and Sevillano cultivars of the olive tree
develop two-seeded fruits at respective frequencies of
14%, 4% and 1% [19]. In Rubiaceae, gender
Cosmocalyx and species such as Zizyphus vulgaris and
Murraya koenigii, fruits generally carry two seeds
[20-22]. Moreover, some species of which Detarium
microcarpum and Orbignya oleifera, produce drupes
containing more than three seeds [23, 24].
From 42 DPP, the growth of the endosperm is
evidenced by a quantity of liquid, increasingly
important, as reported elsewhere [25]. This reflects
continued growth of this tissue, resulting in numerous
cell divisions of the primary endosperm nucleus
taking place at the beginning of fruit formation [26,
27]. The liquid consistency of the endosperm of oil
palm, which lasts until 56 DPP, corresponds to the
coenocytic phase specific to the formation of the
nuclear type endosperm [28, 29]. After 70 DPP, this
tissue acquires a gelatinous consistency. These results
corroborate previous data, which place the transition
from liquid state to semi-gelatinous of the endosperm
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
of oil palm, between eight and ten weeks post-anthesis
[30]. This change in consistency is between 70 and
190 days after anthesis in Pritchardia remota [31]. As
for Cocos nucifera, a part of its endosperm remains
liquid (coconut milk) within the mature fruit [32, 33].
After 70 DPP the mass of the endosperm increases
and it passes from gelatinous to cartilaginous. This
development, which coincides with the stunting of the
diameter of the lodge of the seed, may be associated
with the accumulation of fats. Indeed, the beginning of
lipogenesis in the palm oil seed is between the tenth
and the twelfth week post-anthesis [30, 34].
From 84 DPP endosperm continues to solidify
probably through the synthesis of lipids. These last up
to twenty weeks post-anthesis [34, 35]. This
lipogenesis in the endosperm, combined with thrust
dehydration and a departure of K and Ca, according to
several authors [31, 36, 37], would contribute to
increasing the mass of this tissue and to solidifying it.
In all cases, the endosperm of E. guineensis var. dura
is completely solid at 126 DPP, that is 18 weeks
post-pollination, against 17 weeks post-anthesis
reported for the endosperm of E. guineensis var.
tenera [30] and more than 48 weeks post-anthesis
(340 days) for Pritchardia remota [31]. As for the
seeds of Actinidia chinensis and Lindera melissifolia,
they reach their maximum growth respectively in 80
and 90 days post-anthesis [38, 39]. It is also at 126
DPP that this tissue reaches its maximum growth in
terms of mass, with an average of 0.81 ± 0.04 g. This
value is widely below those observed in Cocos
nucifera, the mass of the seed of which can range
from 354.5 g to 1,107 g [32].
During the first 69 days after pollination, the zygote
(future embryo), is the centre of many divisions that
increase the number of cells [40]. But the endosperm,
which is in its coenocytic phase (liquid consistency),
can not play its role of feeder tissue with the embryo
[28, 41]. So it remains invisible before 70 DPP would
be primarily related to the synchronization between
the formation of the endosperm and the embryo [17].
951
This correlation is necessary nutritionally but
especially mechanically. It is the solidified endosperm
which must maintain the embryo positioned opposite
the germ pore. In Pritchardia remota, the embryo
remains microscopic until 70 days after anthesis [31].
As for embryos of Actinidia chinensis and Lindera
melissifolia, they remain in the two-cell stage until 60
days post-anthesis [38, 39].
After 70 DPP, the embryo grows exponentially
through a significant cell magnification [40].
According to some authors, the weight of the embryo
increases from 80 days after anthesis [37]. This would
be due to the fact that the endosperm of
gelatinous/cartilaginous consistency, fully meets with
it, the role of feeder tissue [27, 40, 41]. The embryo
then lengthens, by its basal pole and almost reaches at
126 DPP its final size and shape [42, 43]. Published
data place the maximum growth of the embryo at 90,
110, 120 and 250 days post-anthesis, respectively for
Lindera melissifolia, Actinidia chinensis, E.
guineensis var. tenera and Pritchardia remota [31,
37-39].
From 126 DPP, the embryo of E. guineensis does
not grow any more. It is the same with Pritchardia
remota, for which there is no difference between
embryos of 250 days and those of 400 days
post-anthesis, in terms of dry mass [31]. And due to
its location and its space in the seed, the embryo of oil
palm belongs to the category of rudimentary embryos
[44]. Embryos of Cocos nucifera, Oryza sativa L. spp.
japonica [33], as well as those of certain
Caprifoliaceae, which occupy a space within the seed
being less than 1/3, even 1/10 [45], are also
rudimentary. On the other hand, in Prunus serotina
and Orozoa paniculosa for example, the embryo
grows by invading most of the major part of the fruit
dedicated to the seed [46, 47].
5. Conclusions
This study shows that the evolution of the seed of E.
guineensis var. dura consists of three main phases.
952
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
Within seven weeks, cells from double fertilization
probably undergo qualitative changes though still
microscopic. Afterward, and during 11 weeks, the
endosperm and the embryo move from insignificant
mass or length to maximum values, which are 0.83 g
and 3 mm respectively. During the last seven weeks,
dimensions of the various tissues of the seed do not
evolve any more. The seed is located in the maturation
phase which prepares it for future germination.
To follow-up this work, it seems appropriate to
analyze in detail what happens to the zygote within
the seven weeks post-fertilization. It is also important
to monitor the chemical composition of the endosperm
from 100 DPP, in order to clarify the implementation
of the seed within the fruit of E. guineensis var. dura.
Later studies will allow identifying the direct primary
effect of Sh gene on the development of the fruit of E.
guineensis Jacq. var. pisifera.
References
[1]
[2]
[3]
[4]
[5]
[6]
[7]
SoyStats. 2007. “World Vegetable Oil Consumption
2006.”
Accessed
January
13,
2010.
http://www.soystats.com/2007/default.htm.
SoyStats. 2014. “World Vegetable Oil Consumption
2013.” Accessed January 5, 2015. http://soystats.
com/wp-content/uploads/SoyStats_2014.pdf.
Jacquemard, J. C. 2011. Le Palmier à Huile. Versailles,
Wageningen, Gembloux: Editions Quæ, CTA, Presses
Agronomiques de Gembloux.
Durand-Gasselin, T., Blangy, L., Picasso, C., De
Franqueville, H., Breton, F., Amblard, P., Cochard, B.,
Louise, C., and Nouy, B. 2010. “Sélection du Palmier à
Huile pour une Huile de Palme durable et responsabilité
sociale”. Oléagineux, Corps Gras, Lipides 17 (6):
385-392. doi:10.1051/ocl.2010.0343.
Skurtis, T., Aïnaché, G., and Simon, D. 2010. “Le
Financement du Secteur de l'Huile de Palme: Pourquoi
les Institutions Financières de Développement Doivent
Continuer à Investir en Afrique.” Oléagineux, Corps
Gras,
Lipides
17
(6):
400-403.
doi:10.1051/ocl.2010.0346.
Demol, J. 2002. Amélioration des Plantes. Application
aux Principales Espèces Cultivées en Régions Tropicales.
Gembloux (Belgique): Les presses agronomiques de
Gembloux.
Meunier, J., and Gascon, J. P. 1972. “Le Schéma Général
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
d'Amélioration du Palmier à Huile à l'IRHO.” Oléagineux
27 (1): 1-12.
Jacquemard, J. C., Baudouin, L., and Noiret, J. M. 2001.
“Oil Palm.” In Tropical Plant Breeding, edited by
Charrier, A., Jacquot, M., Hamon, S., and Nicolas, D.
Montpellier: CIRAD, Science Publishers Inc.
Cochard, B., Amblard, P., and Durand-Gasselin, T. 2005.
“Oil Palm Genetic Improvement and Sustainable
Development.” Oilseeds & fats Crops and Lipids 12 (2):
141-147. doi:10.1051/ocl.2005.0141.
Cochard, B., Adon, B., Rekina, S., Billote, N., de Chenon,
R. D., Koutou, A., Nouy, B., Omoré, A., Purba, A. R.,
Glazsmann, J.-C., and Noyer, J.-C. 2009. “Geographic
and Genetic Structure of African Oil Palm Diversity
suggests New Approaches to Breeding.” Tree Genetics &
Genomes 5 (3): 493-504. doi:10.1007/s11295-0090203-3.
Beirnaert, A., and Vanderweyen, R. 1941. Contribution à
l'Étude Génétique et Biométrique des Variétés d'Elaeis
guineensis Jacquin. East African Standard. Bruxelles:
Institut National pour l'Étude Agronomique du Congo
belge, Série scientifique n 27.
Moretzsohn, M. C., Nunes, C. D. M., Ferreira, M. E., and
Grattapaglia, D. 2000. “RAPD Linkage Mapping of the
Shell Thickness Locus in Oil Palm (Elaeis guineensis
Jacq.).” Theoretical and Applied Genetics 100 (1): 63-70.
doi:10.1007/s001220050009.
Jannot, C. 2002. “Les Déterminants Historiques du
Commerce de l'Huile de Palme. Entre Filière Artisanale
et Agro-industrie: Quel Avenir pour le Palmier en
Afrique?” Presented at the Conference on The Future of
Perennial Crops. Investment and Sustainability in the
Humid Tropics, Yamoussoukro, Côte d'Ivoire.
Corley, R. H. V., and Tinker, P. B. 2003. The Oil Palm.
4th editon. Oxford: Blackwell Science Ltd.
Hartley, C. W. S. 1988. The Oil Palm (Elaeis guineensis
Jacq.). 3rd edition. New York: Longman Scientific &
Technical.
Ngalle, H. B., Bell, J. M., Ngando-Ebongue, G. F., Nyobe,
L., Ngangnou, F. C., and Ntsomboh, N. G. 2013.
“Morphogenesis of Oil Palm Fruit (Elaeis guineensis
Jacq.) in Mesocarp and Endocarp Development.” Journal
of Life Sciences 7 (2): 153-158. doi:10.17265/1934-7391/
2013.02.008.
Hussey, G. 1958. “An Analysis of the Factors Controlling
the Germination of the Seed of the Oil Palm, Elaeis
guineensis (Jacq.).” Annals of Botany 22: 259-284.
Bell, J. M. 2000. Evaluation de l'Offre en Graines de
Palmier à Huile Sélectionné au Cameroun. Vol. I:
Rapport principal. Yaoundé: Association Française des
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
[27]
[28]
[29]
[30]
[31]
Volontaires du Progrès/Ministère de l’Agriculture
(Cameroun).
Cuevas, J., and Oller, R. 2002. “Olive Seed Set and its
Impact on Seed and Fruit Weight.” Acta Horticulturae
586: 485-488.
Delprete, P. G. 1998. “Notes on Calycophyllous
Rubiaceae. Part III, Systematic Position of the Monotypic
Mexican Genus Cosmocalyx and Notes on the
Calycophyll Development.” Brittonia 50 (3): 309-317.
doi: 10.2307/2807774.
Koné, B., Kalinganire, A., and Doumbia, M. 2008. La
Culture du Jujubier: Manuel pour l'Horticulteur Sahélien.
ICRAF Technical Manual N 10. Nairobi: World
Agroforetry Centre.
Handral, H. K., Pandith, A., and Shruthi, S. D. 2012. “A
Review on Murraya koenigii Multipotential Medical
Plant.” Asian Journal of Pharmaceutical and Clinical
Research 5 (4): 5-14.
Balick, M. J. 1979. “Amazonian Oil Palms of Promise: a
Survey.”
Economic
Botany
33
(1):
11-28.
doi:10.1007/BF02858207.
Kouyaté, A. M., Van Damme, P., de Meulenaer, B., and
Diawara, H. 2009. “Contribution des Produits de
Cueillette dans l'Alimentation humaine. Cas de Detarium
microcarpum.” Afrika Focus 22 (1): 77-88.
Rusfiandi, H., Sitorus, A., Forster, B. P., Nelson, S. P. C.,
and Caligari, P. D. S. 2011. “Oil Palm Fruit
Development.” In Proceedings of the Malaysian
International Palm Oil Congress (PIPOC) 161-166.
Percie du Sert, C., and Durrieu, G. 1988. “Edification de
l'Akène et de la Graine de Tournesol (Helianthus annus).”
Informations Techniques du C.E.T.I.O.M. 103: 12-20.
Heller, R., Esnault, R., and Lance, C. 2004. Physiologie
Végétale. 2. Développement. 6e édition. Paris: Dunod.
Vallade, J. 2001. Structure et Développement de la Plante:
Morphogenèse et Biologie de la Reproduction des
Angiospermes. Paris: Dunod.
Judd, W. S., Campbell, C. S., Kellog, E. A., and Stevens,
P. 2011. Botanique Systématique: une Perspective
Phylogénétique. Paris: De Boeck.
Oo, K. C., The, S. K., Khor, H. T., and Ong, A. S. H.
1985. “Fatty Acid Synthesis in the Oil Palm (Elaeis
guineensis): Incorporation of Acetate by Tissue Slices of
Developing Fruit.” Lipids 20 (4): 205-210. doi:
10.1007/BF02534189.
Pérez, H. E., Hill, L. M., and Walters, C. 2012. “An
Analysis of Embryo Development in Palm: Interactions
Between Dry Matter Accumulation and Water Relations
in Pritchardia remota (Arecaceae).” Seed Science
Research
22
(2):
97-111.
doi:10.1017/
953
S0960258511000523.
[32] Zizumbo-Villarreal, D., and Piñero, D. 1998. “Pattern of
Morphological Variation and Diversity of Cocos nucifera
(Arecaceae) in Mexico.” American Journal of Botany 85
(6): 855-865.
[33] Xu, L., Ye, R., Zeng, Y., Wang, Z., Zhou, P., Lin, Y., and
Li, D. 2010. “Isolation of the Endosperm-specific
LPAAT Gene Promoter from Coconut (Cocos nucifera L.)
and its Functional Analysis in Transgenic Rice Plants.”
Plant Cell Reports 29: 1061-1068. doi:10.1007/s00299010-0892-y.
[34] Crombie, M. 1956. “Fat Metabolism in West African Oil
Palm (Elaeis guineensis). Part I. Fatty Acid Formation in
the Maturing Kernel.” Journal of Experimental Botany 7
(2): 181-193. doi:10.1093/jxb/7.2.181.
[35] Boatman, S. G., and Crombie, M. 1958. “Fat Metabolism
in the West African Oil Palm (Elaeis guineensis).”
Journal of Experimental Botany 9 (1): 52-74.
doi:10.1093/jxb/9.1.52.
[36] Prevot, P. 1962. Données Récentes sur la Physiologie du
Palmier à Huile. Physiologie des Plantes Tropicales
Cultivées. Paris: ORSTOM.
[37] Aberlenc-Bertossi, F., Chabrillange, N., Corbineau, F.,
and Duval, Y. 2003. “Acquisition of Desiccation
Tolerance in Developing Oil Palm (Elaeis guineensis
Jacq.) Embryos in planta and in vitro in Relation to Sugar
Content.” Seed Science Research 13 (2): 179-186.
doi:10.1079/SSR2003135.
[38] Hopping, M. E. 1976. “Structure and Development of
Fruit and Seeds in Chinese Gooseberry (Actinidia
chinensis Planch.).” New Zealand Journal of Botany 14
(1): 63-68. doi:10.1080/0028825X.1976.10428651.
[39] Connor, K., Schaefer, G., Donahoo, J., Devall, M.,
Gardiner, E., Hawkins, T., Wilson, D., Schiff, N., Hamel,
P., and Leininger, T. 2007. “Development, Fatty Acid
Composition and Storage of Drupes and Seeds from
Pondberry
(Lindera
melissifolia).”
Biological
Conservation
137
(4):
489-496.
doi:10.1016/
j.biocon.2007.03.011.
[40] Natesh, S., and Rau, M. A. 1984. “The Embryo.” In
Embryology of Angiosperms, edited by Johri, B. M.
Berlin: Springer-Verlag.
[41] Laberche, J. C. 2004. Biologie Végétale. 2e édition. Paris:
Dunod.
[42] Anonymous. 1980. La Culture du Palmier à Huile.
Fascicule I : Classification, Morphologie et Biologie. La
Mé: Institut de Recherche pour Les Huiles et Oléagineux
(France).
[43] Ataga, C. D., and van der Vossen, H. A. M. 2007. “Elaeis
guineensis Jacq.” In Ressources Végétales de l'Afrique
954
Morphogenesis of Oil Palm (Elaeis guineensis Jacq.) Fruit in Seed Development
Tropicale 14. Oléagineux, edited by Mkamilo, G. S., and
van der Vossen H. A. M. Wageningen: Fondation
PROTA, Backhuys Publishers, CTA.
[44] Meyer, D. J. L. 2005. “Seed Development and Structure
in Floral Crops.” In Flower seeds: Biology and
Technology, edited by McDonald, M. B., and Kwong F.
Y. Wallingford (UK): Elsevier.
[45] Jacobs, B., Lens, F., and Smets, E. 2009. “Evolution of
Fruit and Seed Characters in the Diervilla and Lonicera
Clades (Caprifoliaceae, Dipsacales).” Annals of Botany
104 (2): 253-276. doi:10.1093/aob/mcp131.
[46] Labrecque, M., and Barabé, D. 1984. “Développement
du Fruit de Prunus serotina (Rosaceae).” Revue
Canadienne de Botanique 62 (2): 195-206.
doi:10.1139/b84-033.
[47] Teichman, I. V. 1993. “Development and Structure of the
Seed of Ozoroa paniculosa (Anacardiaceae) and
Taxonomic Notes.” Botanical Journal of Linnean Society
111 (4): 463-470. doi:10.1111/j.1095-8339.1993.
tb01915.x.