3. Endah R. Palupi_VOL2_2014.cdr


Abstract

Large scale exploitation of for biofuelJatropha curcas

production is restrained by low productivity hence

economically not pro�table. One of the main constraints

is due to limited number of female �owers in an

in�orescence which eventually develop into fruits that

bear seed. Investigation on �oral biology and

reproductive potential of the species had been carried

out, but seems to vary among sites The research was.

conducted to study reproductive success and the

compatibility among Indonesian accessions.Jatropha

The research was set up in two experiments. The �rst

experiment was conducted at the seedJatropha

orchard, Pakuwon, Sukabumi, West Java from April to

July 2007 using four-year- old trees of accessions from

Lampung, Banten, West Java, and Central Java. The

second experiment was conducted at Leuwikopo

Experimental Station of Bogor Agricultural University

from April to July 2008 using one-year-old trees of

accessions from Lampung, Bengkulu, Palembang, and

Kediri. Flowers were obtained from controlled self and

cross-pollinated as well as left for open-pollination. The

result showed that reproductive success varied among

accessions; the greatest success was 0.73 obtained

from a West Java accession and the least was 0.53 from

Banten accession. The accessions wereJatropha

categorized as partially self-incompatible as indicated

by index of self-incompatibility (ISI) that ranged 0.93-

0.99. Banten accession produced highly viable and

vigorous seeds regardless of pollination methods;

accessions of Central Java produced higher viability

seeds when cross-pollinated within accession, whereas

those from West Java and Lampung produced higher

viability seeds when self-pollinated.

Keywords: accessions, , self-Jatropha curcas

pollination, self-incompatibility, seed

viability

Introduction

The need of renewable energy has encouraged many

parties to �nd sources of biofuel. isJatropha curcas

considered as one of the potential species not only for

biofuel production but also biogas and compost

(Openshaw, 2000, Tiwari et al., 2007, Achten et al.,

2008). D speciesrought tolerant can survive in marginal

land thus avoid competition with food crops which can

only grow in fertile land. However, large scale

exploitation is restraint to low productivity due to the low

number of female �owers, i.e. averaged 10 female

�owers per in�orescence (Adikarsih and Hartono,

2007). Moreover a long-term systematic breeding

program has not been set up which make the species is

still considered as wild and exhibits variability in

productivity among individuals (Achten et al., 2008).

The biodiesel development program in Indonesia has

been set up to grow plantations consisting of 1.5 million

ha of oil palm, 1.5 million ha of , 0.75 million haJatropha

of sugar cane and 1.5 million ha of cassava. The

development of 1.5 million ha of plantationsJatropha

during 2007-2010 required about 900 ton of seeds

(Hasnam, 2007) or about 0.6 kg.ha . Seed procurement
-1

is also facing several limitations that contributed to low

seed viability such as time of harvest in relation to fruit

maturity, seed processing and drying (Sudjindro, 2008).

The project was started with the exploration of Jatropha

germplasm in nine provinces which consisted of 54

districts and 200 000 stem cuttings and seeds had been

collected from these areas. The collected germplasm

were then grouped into 12 accessions, i.e. West

Sumatera, Lampung, Banten, West Java, Central Java,

East Java, West Nusa Tenggara, East Nusa Tenggara,

South Sulawesi, Gorontalo and Maluku. Variations in

plant morphology including leaf thickness, leaf shape

and size, leaf color, pedicel length, fruit shape and size,

seed weight and size, number of seed per capsule were

found among the accessions (Hasnam, 2007).

Reproductive success and compatibility among accessions of Jatropha
curcas in Indonesia.

Endah R. Palupi *, Ade S. Ahmad , Ro�q Affandi , Abdul Qadir , and Eni Randriani
A A A A B

Departmen Agronomy and Horticulture, Bogor Agricultural University, Bogor, Indonesia 16680
A

Indonesian Centre for Estate Crops Research and Development, Sukabumi, Indonesia
B

*Corresponding author; email: erpalupi@yahoo.co.id

RESEARCH ARTICLE

11

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The germplasm were then planted in three locations:

Pakuwon, Sukabumi, West Java representing wet

areas, Asembagus, Situbondo, and East Java

representing dry areas, and Muktiharjo, Pati Central

Java representing moderately dry areas. After a mass

selection the �rst generation of improved-population

was obtained in 2006, i.e. IP-1P (Pakuwon), IP-1A

(Asembagus), and IP-1M (Muktiharjo) with productivity

of about four to �ve t.ha .year at the fourth year after
-1 -1

planting. The second generation of the improved-

population (IP-2) had a higher productivity of about six to

seven t.ha .year at the fourth year after planting. The
-1 -1

third generation (IP-3) was expected to have

productivity of about eight to ten t.ha .year after the
-1 -1

fourth year. After the third generation of improved-

population a long-term breeding plan will be required to

increase productivity further, using either conventional

or molecular techniques in order to become aJatropha

more economically attractive (Heliyanto et al., 2008).

Conventional technique for plant improvement through

controlled pollination or hybridization requires

information on �owering phenology and pollination

system as well as compatibility among accessions.

Hartati (2008) studied the �owering phenology of

Jatropha in Pakuwon, Sukabumi during April-October

and reported that pollination was best conducted in

either late morning (when the stigma has completely

splayed), or afternoon on the �rst day of anthesis,

although the pistillate (female) �ower lasts for several

days. This research was aimed at studying �owering

biology, reproductive success of several accessions

and the compatibility among accessions of inJatropha

Indonesia.

Materials And Methods

The research was set up in two experiments. The �rst

experiment was conducted at the SeedJatropha

Orchard, Pakuwon, Sukabumi, West Java, about 450 m

above sea level, with Latosol soil and type B climate

(Oldeman) from April to July 2007. Four-year-old plants

from four accessions were used i.e. accessions from

Lampung, Banten, West Java, and Central Java with 20

plants from each accession. The second experiment

was conducted at Leuwikopo Experimental Station,

Bogor Agricultural University, about 250 m above sea

level, from April to July 2008. One-year-old plants of

accessions from Lampung, Bengkulu, Palembang, and

Kediri (from stem cuttings) taken from the seed orchard

in Pakuwon were used with 20 plants from each

accession.

Type of in�orescence, ratio of male to female �owers, as

well as time and duration of blooming were observed.

Reproductive success, which was de�ned as the

number of ovules that develop into viable seeds (Wiens

et al., 1987) was observed in open-pollinated population

during the �rst and second experiment which was

started with the number of in�orescence per plant and

number of female or hermaphroditic �ower per

in�orescence (Fl/In�). Fruit set (Fr/Fl) was calculated as

the ratio of female/hermaphroditic �owers that

developed into mature fruits in an in�orescence,

whereas number of ovule per �ower (O/Fl) was counted

as averaged of 20 �owers per accession, which resulted

in three ovules per �ower. Therefore seed set (Sd/O)

was calculated as the proportion of the three ovules that

developed into viable seeds in a fruit. Reproductive

success was calculated from Fr/Fl ratio and Sd/O ratio.

The �owers were tagged with color threads when once

opened. The number and time of �ower or fruits abortion

were observed every alternate day. The experiment was

arranged in a completely randomized design and

analyzed using Duncan's multiple range tests (DMRT)

t o c o m p a r e t h e r e p r o d u c t i v e s u c c e s s a m o n g

accessions.

The compatibility among accessions in the �rst

experiment (four-year-old plants) was recorded from

four types of hand controlled-pollinations, i.e.:

1. Intra-self-pollination (SP-intra): pistillate �owers

were pollinated with pollen from staminate �owers

of the same in�orescence.

2. Inter-self-pollination (SP-inter): pistillate �owers

were pollinated with pollen from staminate �owers

of different in�orescence of the same plant.

3. Intra-cross-pollination (CP-intra): pistillate �owers

were pollinated with pollen from staminate �owers

of other plants within the same accession.

4. Inter-cross-pollination (CP-inter): pistillate �owers

were pollinated with pollen from staminate �owers

of other accession. Accession from South Sulawesi

was used as pollen donor for the four selected

accessions because it had high staminate �ower

production.

All pistillate �owers were bagged at 06.00-07.00hrs in

the morning and pollinated during 10.00-12.00hrs.

Based on the results from the �rst experiment self- and

cross-pollination of the second experiment (on one-

year-old plants) were arranged as follows:

1. Self-pollination: pistillate �owers were pollinated

with pollen from staminate �owers of the same or

different in�orescence of the same plant.

2. Cross-pollination: pistillate �owers were pollinated

with pollen from staminate �owers of other

accession. IP-1P was used as pollen donor for the

four selected accessions.

The observation on each accession included fruit set

from self- and cross-pollination, index of self-

12 Endah R. Palupi, Ade S. Ahmad, Ro�q Affandi, Abdul Qadir, and Eni Randriani

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incompatibility. Seed quality was determined based on

germination percentage, and germination speed was

analyzed according to ISTA (2007). The data was

analyzed using split-plot design, with accession as the

main plot and pollination type as the sub-plots.

Index of self-incompatibility (ISI) was de�ned as the ratio

of fruit set from self-pollination to cross-pollination. The

ISI values were then classi�ed into: ISI 1: self-≥

compatible; 0.2<ISI<1: partially self-incompatible;

ISI<0.2: mostly self-incompatible; ISI=0: completely

self-incompatible (Zapata and Arroyo, 1978).

RESULTS AND DISCUSSION

The �rst in�orescence of the one-year-old plants was

commonly unisexual. Staminate in�orescences were

observed in Lampung and Kediri accessions whereas

pistillate in�orescences in Bengkulu and Palembang

accessions. The subsequent in�orescences in all

plants were bisexual. In most cases staminate and

pistillate �owers were born on the same in�orescence

(monoecious) and rarely staminate and hermaphroditic

(andromonoecious) (Figure 1).

Most of the plants from Central Java produced

staminate and hermaphroditic �owers. The �ower sex

was indicated by the size of the �ower bud; the

hermaphroditic �ower buds was the largest followed by

pistillate and staminate �ower buds. The staminate

�owers of the four-year-old plants usually bloomed

around six days earlier than the pistillate �owers and

�owering continued for several days. The pistillate

�owers bloomed only for two to �ve days and the

�owering period coincided with that of staminate

�owers. On the other hand, the pistillate �owers of the

one-year-old plants bloomed 2 days earlier than the

staminate �owers and last for 2-6 days, followed by the

staminate �owers for several days. In this case only late

blooming pistillate �owers coincided with the blooming

staminate �owers. Raju and Ezradanam (2003)

reported that is a cross pollinating species,Jatropha

therefore different blooming time of male and female

�owers within an in�orescence is bene�cial to prevent

sel�ng. Battacharya et al. (2005) added that spp.Apis

were the most frequent visitor of �owers at theJatropha

same time they deposited pollen grains on the stigmatic

surface, thus generating cross-pollination.

Figure 1. in�orescence: (A) male (red arrow)Jatropha

and female (yellow arrow) �owers (B) male

(red arrow) and hermaphroditic (yellow

arrow) �owers

The number of in�orescence of the four-year-old plants

varied among accessions and was fewer compared to

that of the one-year-old plants. However, the

A B

Note: Numbers of the same set of experiment and the same column followed by different letters were signi�cantly different based
on DMRT at = 0.05
1
Number of blooming in�orescence per plant

2
Percentage of staminate in�orescence: in�orescence that produces only staminate �ower

3
Number of female or hermaphroditic �owers per in�orescence

4
Number of maturing fruits per in�orescence

5
Fruit to �ower ratio (female or hermaphroditic): the proportion of female or hermaphroditic �ower that develop into mature

fruit
6
Number of �lled seeds per fruit

7
Seed to ovule ratio: the proportion of ovule that develop into viable seed (based on three ovules per �ower)

8
Reproductive success

13Reproductive success and compatibility among accessions of Jatropha..........

Table 1. Reproductive characters and reproductive success of each accession (from open pollination)

Accassion

Lampung
Banten
West Java
Central Java
Average

Lampung
Bengkulu
Palembang
Kediri
Average

In�/Pl
1

3.90b
5.15a
2.65c
3.40bc

5.57
6.02
6.29
5.02
5.73

St. In�.(%)
2

14.1
21.4
15.1
17.1
16.9

1.7
0
0

0.9
0.7

Fl/In�
3

1.93
5.33
3.50
4.63
4.60

8.88a
7.35ab
9.10a
6.34b

Fr/ln�
4

3.80
3.69
2.62
3.98
3.52

5.63
5.82
6.46
4.75
5.67

Fr/Fl
5

0.77ab
0.69bc
0.75bc
0.86ab

0.62
0.80
0.73
0.73
0.72

Sd/Fr
6

0.36
2.27
2.28
2.57
2.37

2.74
2.76
2.80
2.66
2.74

Sd/O
7

0.78
0.76
0.76
0.85
0.79

0.88
0.94
0.92
0.86
0.90

Rs
8

0.61b
0.53b
0.59b
0.73a

0.56
0.74
0.68
0.66
0.66

Four-year-old plants

One-year-old plants

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percentage of staminate in�orescence was higher in the

older (averaged 16.9%) than the younger plants

(averaged 0.7%) (Table 1). The four-year-old plants

were planted in the �eld with 2 x 2 m spacing; while the

one-year-old plants were planted in polybags. It is

possible that the higher light intensity in the �eld led to

the formation of more male �owers. Investigation on

environmental factors affecting sex ratio will be valuable

to increase production of female �owers which could

lead to an increase in fruit yield.

Accession from Banten produced the greatest number

of in�orescence whereas that of West Java had the

fewest. The number of pistillate or hermaphroditic �ower

per in�orescence as well as the number of fruits per

in�orescence was not signi�cantly different among

accessions, ranged 3.5-5.33 in the four year-old and

ranged 6.3-9.1 in the one-year-old plants (Table 1).

Again, the data showed that the performance of the one-

year-old was better than the four-year-old plants.

However, the fruit to �ower ratio (fruit set) from both

plants was similar (Table 1), ranged 0.62-0.86 indicating

that the number of pistillate or hermaphroditic �ower per

in�orescence was a major yield component and at the

same time the limiting factor of kernel production.

The data implied that increasing the number of pistillate

�ower per in�orescence would be the key to increase

the productivity. Not all pistillate or hermaphroditic

�owers can develop into mature fruits. Bhattacharya et

al (2005) reported that fruit set from pistillate �owers was

only 50%, due to fruit abortion during development. In

this research, abortion at �owering stage, i.e. �owers

that aborted within 4 days after anthesis, was around 5%

in the four-year-old and 1% in the one-year-old plants.

The abortion during fruit and seed development ranged

9-33%.

The average number of seeds per fruit in both

experiments ranged 2.27-2.57 and 2.66-2.80 although

on average three ovules were found in one ovary.

Hermaphroditic �owers in this experiment can produce

up to four seeds per fruit. The seed to ovule ratio (seed

set) was 0.76-0.85 in the four-year-old plants and 0.86-

0.92 in the one-year-old plants, and did not vary among

accessions. The data indicated that seed set was

reasonably high although not all ovules developed into

viable seeds. Insuf�cient pollination could be the cause

of the less than maximum seed set and could be

overcome by increasing the population of the insect

pollinators. Social bees, i.e. andApis cerana Apis

dorsata were reported as effective pollinators for

Jatropha in Indonesia (Rianti et al., 2010), hence could

be employed to increase seed production. In Nigeria,

however, where the most effective insectJatropha

pollinators were not social bees, i.e. Chrysomya

chloropyga Eristalis tenax(Diptera-Calliphoriade) and

(Diptera-Syrphidae) (Alamu et al., 2013), introduction

and maintenance of the insect population could be more

dif�cult.

Data on reproductive success showed similar range

from the four-year-old and the one-year-old plants,

between 0.53-0.74, meaning that from 100 ovules

produced, only 53-74 developed into viable seeds. This

data indicated that seed production was lower than the

yield potential; therefore cultural techniques need to be

explored to increase fruit and seed set.

Abortion at the �owering stage following controlled

pollination was low, i.e. < 3% in cross-pollination and

self-pollination during both experiments. However,

abortion at the fruit development stage was as high as

32% in the four-year-old and 20% in the one-year-old

plants. Fruit abortion in self-pollination was similar to

that in cross-pollination. The data indicated that the

abortion was not due to incompatibility as fruit set from

self-pollination was not signi�cantly different from that of

Fruit set (%) Seed set (%)
1 Fruit set (%) Seed set (%)

Lampung 74.3 54.3 65.7 51.4 1.13

Banten 61.4 42.9 65.7 40.5 0.93

West Java 70.0 59.5 64.3 51.4 1.09

Central Java 64.3 44.8 78.6 57.1 0.82

Lampung 81.1 88.3 85.1 86.2 0.95

Bengkulu 80.2 89.1 80.2 91.0 1.00

Palembang 72.0 90.2 78.1 86.1 0.92

Kediri 75.2 87.1 89.3 86.0 0.84

One-year-old plants

Accession
Self-pollination Cross-pollination

ISI
2

Four-year-old plants

Table 2. Fruit set and seed set from self and cross-pollination

Note: Seed set was calculated from the number of sound seed divided by the number of total ovule assuming that
1

there were three ovules per �ower

ISI (index of self-incompatibility): ratio of fruit set from self-pollination to cross-pollination
2

14 Endah R. Palupi, Ade S. Ahmad, Ro�q Affandi, Abdul Qadir, and Eni Randriani

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cross-pollination (Table 2). Fruit abortions occurred at

different stages of development, but mostly were during

the early stages when the size was less than half of the

mature fruit. Observation on the causes of the abortion

would be useful to �nd measures to increase kernel

production.

Fruit set and seed set of the four pollination types in the

four-year-old plants (SP-intra, SP-inter, CP-intra and

CP-inter) were not signi�cantly different, so the data was

presented as self- and cross-pollination (Table 2). Fruit

set did not vary among accessions either in the �rst or

second experiments. It was surprising that cross

pollination did not result in higher fruit and seed set than

self-pollination, which indicated that was notJatropha

an obligate cross pollinated species. These results were

in contrast to that reported by Raju and Ezradanam

(2002) in India that fruit set from hand cross-pollination

was higher (96%) than that of hand self-pollination

(77%). Kaur et al (2011) also reported that in the central

region of Punjab the fruit set from cross-pollination was

higher (93.2%) than that of self-pollination (72.2%). The

average index of self-incompatibility in this research

was 0.99 and 0.93 in the four-year-old and one-year-old

plants, respectively, so is categorized as aJatropha

partially self-incompatible species, supporting the

research result of Wang and Ding (2012) that J. curcas

has both self-pollination and cross-pollination systems.

This is contradictory to Heller (1996) who stated that

Jatropha was a cross-pollinating species. Given the

data it is possible that the seeds produced in any

Jatropha plants in Indonesia were the results of self-

pollination with ants as the effective pollinator ( etLuo
al. 2012).

The germination percentage of the self-pollination

seeds was not signi�cantly different from the cross-

pollination seeds, supporting the idea that wasJatropha

not an obligate cross pollinating species. The four-year-

old accession from Banten produced highly viable

seeds from both self- and cross-pollination. Lampung

and Central Java accessions produced highly viable

seeds (> 80%) from self-pollination, whereas cross

pollinated seeds from West Java accession had higher

viability than self-pollinated (Table 3).

Slightly different results were obtained from the one-

year-old plants in which cross-pollination produced

better quality seeds than self-pollination as indicated by

germination rate of > 80% and germination speed of ≥

9.46 %.day (Table 4). In general Banten, Bengkulu and
-1

Kediri accessions produced highly viable seeds

regardless of pollination systems. It would be interesting

to learn the reproductive success of the self- and cross-

pollinated progenies. A study in Malaysia showed

positive heterosis from crosses of particular superior

parents (Islam et al, 2011) which could potentially lead

to the development of hybrid varieties of Jatropha

curcas.

15Reproductive success and compatibility among accessions of Jatropha..........

Table 3. Seed germination (%) and germination speed (%.day ) based on pollination systems
-1

and accessions from four-year-old plants

Note: Numbers followed by the same letter of the same column and row were not signi�cantly

different based on DMRT at     = 0.05

Accession

Lampung

Banten

West Java

Central Java

Lampung

Banten

West Java

Central Java

SP-intra

96.67a

90.48ab

72.22de

95.83a

8.53ab

8.00abc

6.60cd

8.34ab

SP-inter

82.22abcde

92.31abcde

73.33cde

88.89abcd

7.47bcd

8.18a

6.39d

7.99abc

CP-intra

81.82abcde

90.91abcde

89.58abcde

85.97abcde

7.42bcd

8.13abcde

8.33ab

8.24ab

CP-inter

69.84e

97.44a

77.08bcde

40.48f

6.55cd

9.30a

7.20bcd

3.53e

Germination (%)

Germination speed (%.day )
-1

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Accession

Germ
1
. (%) GR

2
(%.day

-1
) Germ

1
. (%) GR

2
(%.day

-1
) Germ

1
. (%) GR

2
(%.day

-1
)

Lampung 80.54 9.67 73.71 8.73 86.41 10.34

Bengkulu 85.02 10.35 84.90 8.54 85.28 10.32

Palembang 80.98 9.82 78.61 9.53 81.20 9.46

Kediri 78.49 9.84 85.42 9.72 87.51 10.78

Cross-pollinationOpen-pollination Self-pollination

Table 4. Germination (%) and germination speed (%.day ) based on pollination system and accessions from
-1

one-year-old plants

Note: Germination percentage indicating seed viability
1

Germination speed indicating seed vigor
2

16 Endah R. Palupi, Ade S. Ahmad, Ro�q Affandi, Abdul Qadir, and Eni Randriani

The germination speed, which is an indication of seed

vigor, showed similar trends to germination percentage

in which self- and cross-pollination resulted in non-

signi�cantly different rates. The one-year-old plants

tend to demonstrate higher germination speed than the

four-year-old plants. Banten accession germinated at a

faster rate (Table 4) regardless of pollination types. Self-

pollinated seeds from West Java were slower to

germinate compared to cross-pollinated ones. These

data were in line with data on germination percentage

that cross pollination between accessions could give

negative effect on seed viability. In general, although

Banten accession had the lowest reproductive success,

hence seed production, this accession produced high

quality seeds, which is an important character for a

conventional breeding program.

Conclusion

Reproductive success varied among accessions, the

highest was from West Java of 0.73 and the lowest from

Banten of 0.53.
Jatropha sccessions (Lampung, Banten, West Java,

Central Java, Bengkulu, Palembang and Kediri) are

partly self-incompatible with self-incompatibility index

range of 0.93-0.99.
Pollen source did not affect fruit set and seed set, but

affected seed germination and speed of germination.

Acknowledgment

We thank the Indonesian Centre for Estate Crops

Research and Development for the permission to use

seeds from seed orchard in Pakuwon, WestJatropha

Java for this research.

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