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GANODERMA DISEASE OF THE OIL PALM: IMPLEMENTATION OF AN EARLY ARTIFICIAL INOCULATION TEST TO SCREEN OIL PALM PROGENIES FOR THEIR LEVEL OF RESISTANCE AND HYPOTHESIS ON NATURAL INFECTION F. BRETON, R. MIRANTI, Z. LUBIS, Z. HAYUN, S. UMI, A. FLORI, S.P.C. NELSON, T. DURAND-GASSELIN, J.C. JACQUEMARD and H. DE FRANQUEVILLE PT Socfin Indonesia Sumatra Bioscience (Lonsum) Oil Palm Breeding Unit

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GANODERMA DISEASE OF THE OIL PALM:

IMPLEMENTATION OF AN EARLY ARTIFICIAL INOCULATION TEST TO

SCREEN OIL PALM PROGENIES FOR THEIR LEVEL OF RESISTANCE

AND HYPOTHESIS ON NATURAL INFECTION

F. BRETON, R. MIRANTI, Z. LUBIS, Z. HAYUN, S. UMI, A. FLORI, S.P.C. NELSON,

T. DURAND-GASSELIN, J.C. JACQUEMARD and H. DE FRANQUEVILLE

PT Socfin

Indonesia

Sumatra Bioscience

(Lonsum)

Oil Palm

Breeding Unit

INTRODUCTION

• Three major diseases seriously limit oil palm cultivation in each of itsmain growing areas:

– Bud rot disease(s) or PC in Latin America, which can destroyplantations of several thousand hectares. Recent findings on the possiblerole of Phytophthora palmivora are promising in terms of research anddisease management

– Vascular wilt in Africa, caused by Fusarium oxysporum f.sp. elaeidis, asoil-borne fungal pathogen. Losses increase with the successive cropcycles (generation), if a non resistant material is planted. Fusarium wilt, asan example, will be briefly evoked in some following slides

– Basal stem rot (BSR), mainly caused by Ganoderma boninense inSoutheast Asia, another soil-borne fungal pathogen. It starts to inducedamages in Central Africa and to a lesser extent in South America. Thenumber of successive generations is also of importance

Incidence of Ganoderma (BSR)

• In Southeast Asia, specially in North Sumatra (Indonesia), many oil palm

plantations are planted in their 4th generation. 80% of the palms can have

been affected by the end of the 3rd generation

• In (Central) Africa, most of the plantations are old second generations. It

is frequent that BSR appear when the plantations are older than their

normal economic life. Ganoderma can interact with Fusarium wilt and then

install before the next replanting

• In South America, where most of the plantations are at the end of the first

generation - early second generation, Ganoderma is still contained at a

low level and, of course, PC constitutes a much higher threat and challenge.

Part B:

A Lignified Star-Shape Cavity at Root-Bole Interface:

An Appropriate Culture Chamber for Ganoderma boninense

Part A:

Early Screening Test to Evaluate Resistance/Susceptibility Level of Oil Palm

Progenies to Basal Stem Rot Disease

After a brief presentation of BSR, this communication will be divided in two parts

Leaf symptom SporophoresRotten tissue

Three kinds of disease symptoms can be observed “independently”

Symptoms on mature palms

Palm losses due to Ganoderma disease

Palm losses due to Ganoderma disease

Some recommendations

• Elimination of trees affected by Ganoderma

• Bole extraction (do not cover with soil and weeds)

• Dig a sanitation hole :1,5 x 1,5 x 1m (hxLxd)

• Respect the former density when replanting

Avoid :

Replanting at 160 palms/ha

Red circles:

potential focuses

MapInfo simulation

Part A:

Early Screening Test to Evaluate Resistance/Susceptibility Level of Oil Palm

Progenies to Basal Stem Rot Disease

Fusarium wilt experience

Two types of symptoms on

mature palms:

Acute, generally killing the palm

six months after they appear

Chronic, stunting the growth of

the oil palm, which only produces

a few lightweight bunches

Fusarium wilt symptoms on mature palms

Resistance to Fusarium wilt

Substantial differences in performance exist in the field depending on

planting material origin

This differences can be detected through artificial inoculations of the

pathogen in prenursery and Cirad has implemented an early screening

test since several decades

Progeny A Progeny B

Each test usually compares 200

crosses, each represented by 8

replicates of 20 seedlings

Results are obtained 5 months after

inoculation

The results are usually well correlated

to field results

They are expressed as a “vascular wilt

index”

Screening for Fusarium wilt resistance

Dabou experimental prenursery, CNRA, Ivory Coast

• Base 100: Mean of the test100

90

80

110

120Susceptibility

Resistance

Fusarium wilt index

Such an index will be applied for potential Ganoderma results

0,00

5,00

10,00

15,00

20,00

25,00

30,00

35,00

40-49 50-59 60-69 70-79 80-89 90-99 100-109 110-119 >120

Index prenursery

% V

ascu

lar

wil

t in

fie

ld

Relationship between prenursery index and field results

• High differences between both pathogens, Fusarium and Ganoderma

• Are there differences of susceptibility to Ganoderma within the plantingor breeding material ?

• About Ganoderma, let us quote R.H.V. Corley & P.B. Tinker (2003), in“The Oil Palm”, 4th Edition, p. 413 :

“It appears to us that, in the longer term, the best approach tocontrolling the disease in areas where it is prevalent may be todevelop tolerant material, using nursery inoculation for screening,in much the same way as has been done for Fusarium wilt.”

• We share this point of view, breeding being a major component of anintegrated control. A research program has started in 2002-2003.

Such an early detection applicable to Ganoderma disease ?

0

5

10

15

20

25

30

35

40

1992 1993 1994 1995 1996 1997 1998 1999 2000

Years

% G

an

od

erm

a

C 2501 (b)

SOC 0903

(a)

SOC 0901

LMC 063 (b)

LMC 043 (a,b)

LMC 044

LMC 051 (b)

LMC 074

BB CL 4 (1989 planting, 3 rd

planting cycle)Thus possible to

identify susceptible/resistant material soon after

field planting

Genetic trials have led to the detection of significant differences in

susceptibility to Ganoderma, in relation to the genetic origin of the material

exposed to the disease (de Franqueville et al., 2001, Durand-Gasselin et al.,

2005)

But

How to identify early (before planting) the sources of resistance used in

breeding programmes ?

Scientific collaboration

on the oil palm Ganoderma disease (BSR) in North Sumatra

(PT Socfindo – Sumbio/Lonsum - Cirad)

OBJECTIVE

To implement an early screening method for oil palm “resistance/tolerance” to Ganoderma

Characteristics of the method to set up :

1) Discriminating (susceptibility/resistance)

2) Closely correlated to field observations (in natural infection)

3) Reproducible (standardisation)

4) Easy and rapid (several hundreds of progenies per year prenursery stage)

In Previous Study

(Breton et al., 2005)

Characterisation and standardisation of several major parameters ensuring a successful prenursery

screening test, based on artificial inoculation of the Ganoderma

Preparation of inoculum (laboratory) :

-Nature of substrate source (RWBs : Rubber Wood Block)

-size of the inoculum source (6x6x3cm)

-Preparation of the RWBs prior to inoculation with Ganoderma isolates

-incubation time of Ganoderma inoculated RWBs (12 to 14 weeks)

-Conditions of incubation (dark, 27°C, 34% relative humidity )

Artificial inoculation of plant material (nursery) :

-the physiological stage of the planting material (germinated seed, GS)

-Volume of prenursery polybag (20x30cm)

-Distance within polybag between GS with inoculum source (5cm)

-prenursery shade and temperature (80% light filtration)

Symptoms obtained after artificial

inoculation

0

10

20

30

40

50

60

70

80

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

Weeks

% o

f in

fecte

d s

eed

lin

gs

0

10

20

30

40

50

60

70

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

Weeks

% o

f in

fecte

d s

eed

lin

gs

BSR disease symptoms obtained in nursery 3-4 months after germinated seeds inoculation

Implementation of an early screening test

Index Evolution During Recording Period

Progenies code tested in

Trial 1

Index (based on external symptoms)

16W 18W 20W 22W 24W 26W 28W

12675 164 152 135 127 121 117 116

12700 78 95 82 81 78 89 88

15270 267 210 178 167 158 154 143

12751 60 62 82 89 96 96 97

12752 78 86 96 97 89 94 95

15271 86 95 109 108 117 121 113

12773 103 119 119 116 119 114 118

12276 52 57 76 78 78 81 82

15272 138 119 112 110 114 112 115

15273 112 100 102 110 112 104 103

11672 95 105 86 89 85 83 88

12444 60 57 76 75 80 77 84

11143 52 67 79 83 89 96 97

15274 26 38 36 43 41 48 46

15275 129 138 132 127 123 114 115

Trial mean (% infection) 11.6 21.0 30.3 37.1 43.7 48.1 52.4

Correlation with index 28W 0.83 0.86 0.95 0.96 0.98 0.98 1.00

Progenies code tested in

Trial 4

Index (based on external symptoms)

16W 18W 20W 22W 24W 26W 28W

12675 236 231 199 171 153 140 135

12700 41 30 50 68 78 78 77

12752 82 82 99 100 104 103 104

15271 216 187 163 157 147 142 128

12271 103 97 81 86 89 91 90

12778 164 149 127 114 104 106 108

13790 144 134 163 157 141 132 128

15278 62 60 81 82 95 98 97

15279 21 45 50 57 63 62 77

15280 82 90 72 86 95 109 113

15281 92 119 104 107 101 93 101

15282 10 22 36 54 55 62 59

15283 92 97 122 104 112 114 110

15284 41 52 68 68 69 75 79

15285 113 104 86 89 95 96 95

Trial mean (% infection) 9.7 13.4 22.1 27.9 34.7 38.7 44.4

Correlation with index 28W 0.88 0.88 0.92 0.93 0.96 0.97 1.00

An infection mean of 30% provided useful information on the level of

resistance/susceptibility of tested crosses

Standards crosses Index distribution between

independent tests (base 100)

Categories Codes

Number of independent tests performed

Lower than 100 higher than 100

Average Index (30%)

Data summary < 100 <

S1 3 0 3 156 0-3

S2 11 3 8 123 3-8

S3 8 0 8 142 0-8

S4 3 0 3 156 0-3

S5 4 0 4 134 0-4

S6 3 0 3 154 0-3

S7 4 0 4 155 0-4

S8 7 3 4 120 3-4

S9 11 3 8 114 3-8

Susceptible

S10 9 3 6 114 3-6

M1 4 2 2 97 2-2

M2 6 2 4 109 2-4

M3 3 2 1 94 2-1

M4 4 2 2 98 2-2

M5 14 8 6 95 8-6

M6 20 10 10 100 10-10

M7 4 2 2 108 2-2

M8 6 3 3 99 3-3

M9 6 3 3 102 3-3

Medium

M10 5 3 2 96 3-2

T1 5 5 0 45 5-0

T2 7 6 1 75 6-1

T3 7 6 1 78 6-1

T4 4 4 0 77 4-0

T5 16 14 2 81 14-2

T6 10 10 0 56 10-0

T7 6 5 1 66 5-1

T8 9 9 0 62 9-0

T9 11 10 1 63 10-1

Tolerant

T10 8 7 1 80 7-1

A set of standard crosses allows to link

trials between each others and the

combined analysis of trial results

Standard Crosses

Results demonstrate also the

reproducibility and the

consistency of the test

0,0

0,5

1,0

1,5

2,0

2,5

3,0

3,5

4 8 12 16 20 24 28

Weeks after germinated seeds inoculation

F-V

alu

e o

f P

rog

en

y E

ffe

ct

on

In

fec

tio

n R

ate

TG18

TG19

TG21

Evolution of F-value for three screening

tests during the period of recording the

external disease symptoms

With an average percentage of infected standard crosses of around 30%, F-values do

not vary extensively and relative variation between progenies has stabilized

“Discriminating power” of this screening test estimated by the F-value

0

140

0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50 50-60

Frequency (% infection)

No

. o

f P

rog

en

ies

Te

ste

d

Distribution of the Resistance/Susceptibility to Ganoderma

Within a Genetic Population of Oil Palm

The distribution of the resistance/susceptibility to Ganoderma is continuous and suggests that

more than one or two major genes are involved in providing tolerance/resistance

General Procedure for Routine Screening Work

at PT Socfindo and Sumatra Bioscience

• 100 crosses tested every month

• 5 replicates of 20 germinated seeds per tested cross

• 20 additional seeds per cross are inoculated at the same time for use as replacements four weeks after initial inoculation

• External symptoms are recorded every month then every two weeks when infection level of trial reaches 25%

• Splitting seedlings and final record when average trial is around 30% infection (between 22 to 24 weeks after inoculation)

• The following slide summarizes the schedule of a screening test

Preparation of RWBs

Inoculation of RWBs

Storage of RWBs

Germinated seeds inoculation

Recording of disease symptoms

Splitting of seedlings

then recording symptoms

1 month 3 months 5 to 6 months

Female Origin

Binga x Lobe 75 75

AVROS 72 85 80 79

(MRS x MRS) x Lobe 90 90

Lobe 85 97 91

Binga x Binga 75 81 92 97 77 117 109 116 100 96

Lobe x Lobe 87 108 97

(AVROS x UR Deli) x Binga 102 92 103 99

SF Deli x GM Deli 47 85 108 121 110 94 152 102

GM Deli 109 104 87 117 104

AVROS x Binga 107 106 91 106 111 104

Lobe x GM Deli 93 99 104 123 97 112 118 107

Binga x Pobe 86 84 115 144 107

GM Deli F1 85 137 106 109

DM Deli 89 96 92 111 114 118 151 110

Lobe x SF Deli 107 101 135 114

(GM Deli x MRS) x Lobe 101 125 101 167 124

Index Average 70 86 87 93 97 97 97 98 101 104 105 106 111 111 112 114 118 134 134 152 103

Lob

e x

Lo

be

DM

De

li x

AV

RO

S

(AV

RO

S x

UR

De

li)

x B

inga

Bin

ga x

Lo

be

SP5

40

AV

RO

S x

AV

RO

S

Bin

ga x

Po

be

Yan

gam

bi

x Ya

nga

mb

i

AV

RO

S

Lob

e x

SF

De

li

Bin

ga x

Bin

ga

AV

RO

S x

Bin

ga

(Co

wan

x C

ow

an)

x A

VR

OS

Index Average

Male Origin

(Co

wan

x C

ow

an)

x Lo

be

DM

De

li

(MR

S x

MR

S) x

Lo

be

Lob

e x

GM

De

li

AV

RO

S x

La M

e

(GM

De

li x

MR

S) x

AV

RO

S

(GM

De

li x

MR

S) x

Lo

be

Sources of

resistance

and sources

of

susceptibility

Female Origin

Deli Dabou x Deli Dabou 64 64

Deli Socfindo x Deli Socfindo 85 85

Deli Dabou x Deli Socfin 86 86

Deli Dabou x Deli Socfin 94 95 84 91

Deli Socfindo 80 90 106 104 95

Deli Dabou x Deli Dabou 95 103 99

Deli Dabou x Deli Socfin 101 101

Deli Dabou x Deli Socfin 96 103 120 106

Deli Socfin 83 109 126 110 107

Deli Dabou 96 113 115 108

Deli Dabou x Deli Dabou 111 107 109

Deli Dabou x Deli Dabou 109 109

Deli Socfin x Deli Dabou 105 114 109

Deli Socfin x Deli Socfin 110 110

Angola x Deli Dabou 119 119

Index Average 85 86 86 90 95 101 103 105 109 111 111 101

(La

x La

Mé)

x (

La M

é x

La M

é)

La M

é x

La M

é

La M

é

Yan

gam

bi

Index Average

La M

é x

La M

é

Yan

gam

bi x

Yan

gam

bi

Male Origin

Yan

gam

bi x

Yan

gam

bi

La M

é

La M

é x

La M

é

La M

é x

La M

é

La M

é x

La M

é

Sources of

resistance

and sources of

susceptibility

GROUPE B

(male)org2 parent2

PO

y

yyy

PO

y

yyy

PO

yyyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyy

SL

yyyy

1 131 134

2 148 99

3 129 106

4

5 81 106

6 127 148

7

8 127 134

1 93

2 47 93

3 41 104

4 60 147

5 78 73

6 135 106

7

SL xxxx

SL xxxx

X

GROUP A (female)

Y

123

89

Caution for interpretation of the global index of one category or of one family

NumberProgeny

codeField status 1

Number

of trials 2Index

average

Index distributionTest status

Id 3<100 Id>100

1 12658 Intermediate 4 86 3 1 Resistant to intermediate

2 12675 Susceptible 8 126 2 6 Susceptible

3 15278 - 4 79 3 1 Resistant

4 12700 Resistant 5 75 5 0 Resistant

5 15284 - 4 75 3 1 Resistant

6 12751 Intermediate 4 97 2 2 Intermediate

7 12752 Intermediate 6 109 2 4 Intermediate to susceptible

8 15271 - 8 141 0 8 Susceptible

9 12773 Intermediate 4 101 2 2 Intermediate

10 12276 Resistant 5 46 5 0 Resistant

11 12778 Intermediate 5 91 4 1 Resistant to intermediate

12 2615580 Exp. susceptible 7 113 2 5 Susceptible

13 2648858 Exp. susceptible 8 100 4 4 Intermediate

14 2654198 - 5 74 4 1 Resistant

15 2655003 Susceptible 5 105 2 3 Intermediate to susceptible

16 2648147 - 6 127 2 4 Susceptible

17 2653769 - 5 76 5 0 Resistant

18 2641311 Exp. resistant 4 65 4 0 Resistant

19 2660428 - 4 112 1 3 Susceptible

20 2641666 Exp. resistant 5 77 5 0 Resistant

21 2632316 - 4 95 2 2 Intermediate

22 2649172 Exp. resistant 6 70 6 0 Resistant

CONCLUSION (1)

1) An early and rapid screening test of oil palm progenies to BSR disease has

been developed and validated by using planting and breeding materials from two

Indonesian private companies in a partnership with Cirad: Sumatra Bioscience

(Lonsum) and PT Socfin Indonesia (Socfindo)

2) The results are both consistent and reproducible and correlated to field

observations.

3) This prenursery test using germinated seed allowed the rapid screening of

several hundreds of crosses per year and is highly asset valuable to plant

breeders.

This screening test provides :

1) a method to ensure no highly-susceptible progenies are transferred to the field

for commercial planting,

2) a breeding tool,

- to develop more Ganoderma resistant high yielding planting material,

- to understand the genetics of Ganoderma resistance/susceptibility,

- to investigate Ganoderma infection,

- and as a more general tool to test other methods to control and

prevent Ganoderma.

CONCLUSION (2)

Part B:

A Lignified Star-Shape Cavity at Root-Bole Interface:

An Appropriate Culture Chamber for Ganoderma boninense and

Stromatic-Like Structure Development

A LIGNIFIED STAR-SHAPE CAVITY AT ROOT-BOLE INTERFACE

COMMON TO ALL MATURE PALMS WHATEVER THEIR SANITARY CONDITIONS

This lignified scar will form the future star-shape cavity observed in mature palms.

At the nursery stage, a lignified scar is clearly observed

8 months 18 months 20 months

Lignified Star-Shape Cavity an Appropriate Culture Chamber

for Ganoderma boninense

Suitable conditions for Ganoderma development and infection:

- dark cavity

- lower than ambient temperature

- high humidity

- dense subtrate (lignified oil palm tissues)

- less antagonists than in the open soil (Ganoderma poor competitor)

- attached roots

Production of Stromatic-Like Structure or Pseudo-Sclerotium

(melanised fungal hardened tissue)

Stromatic-Like Structure (SLS) or Pseudo-Sclerotium

No SLS

No infection

SLS

InfectionThis close contact root-SLS is the

preliminary step of the internal invasion

Development of SLS occurred only on

a dense subrate

the presence of this melanised mycelium mass is necessary to induce BSR symptoms

Rhizotron method

(Breton et al., 2005)

0

10

20

30

40

50

60

12 16 20 24 28 32 36 40

Weeks after germinated seeds inoculation

% o

f in

fecte

d s

eed

lin

gs RWB+SLS RWB-SLS

SLS

a

b

c

Stromatic-Like Structure (SLS) or Pseudo-Sclerotium

The infection observed for the treatment

SLS-free RWB correspond to a production

de novo of the SLS

This fungal melanised mass (SLS) need a hardened food base to survive in the soil

and to express its high infectious potential

Stromatic-Like Structure (SLS) in Mature Oil Palm Recently Infected

Stromatic-Like Structure (SLS)

localised only at the external surface of

the lignified star-shape cavity (root-bole

interface)

In nursery trials the RWB provides a dense substrate to reproduce or simulate the role of the

lignified star-shape cavity observed in mature palms

Longitudinal and Transverse Sections of Root-Bole Interface

from Recently Infected Mature Oil Palms

Arrows show the progression of the rotten

tissues from the basal lignified cavity

Indicating

a radial and a centrifugal colonisation

of the bole by Ganoderma

CONCLUSION

- Melanised stromatic-like structure (SLS) or pseudo-sclerotium produced by Ganoderma only on

dense substrates seems to be an essential physiological stage prior the invasion of the oil palm

bole (nursery-field).

- For mature palms, the presence of a lignified star-shape cavity at root-bole interface plays the

role of Ganoderma culture chamber for SLS development.

- Transverse and longitudinal sections of the root-bole interface from recently infected young palm

confirmed a centrifugal and radial initial invasion of the bole from this lignified cavity (major

location for the initial invasion of the fungus inside the bole).

- If no initial penetration points were found beyond the periphery of this lignified area, multiple

penetration points were observed from this cavity which probably involved more than one isolate.

The melanised SLS could be considered as an aggressive or pathogenic stage

in the physiological life cycle of the fungus

PERSPECTIVES

- Insufficient field observations have yet been conducted to establish any relationship

between cavity size with genetic origin of oil palms or environmental factors (soil

characteristics).

- Work is in progress to investigate the relationship between the size of the basal lignified

star-like cavity with the resistance/susceptibility of oil palm or with the kinetic of the bole

invasion by Ganoderma.

- In parallel, localised injections (fungicides and antagonists microorganisms) in and around

this lignified star-shape cavity are being tested.

GENERAL CONCLUSIONS

• Like for Fusarium wilt, it is possible now to screen at an early stage oil

palm progenies for their degree of resistance to Ganoderma

• The high number of tested progenies (100/month) is a recent step and

more and more data will be available

• But, planters must not expect “zero-Ganoderma” progenies, due to the

nature of the fungus, the unknown mechanisms of (partial) resistance

• Elementary cultural practices must be implemented (sanitation, for

example)

• The star-shape cavity might be a very important point to perform very

localized treatments (fungicides or antagonists)

• An integrated disease management is therefore highly possible,

specially when the disease is still at a low level

PT Socfin

Indonesia

Sumatra Bioscience

(Lonsum)

Oil Palm

Breeding Unit