Jean-Philippe Pichaut1, Benoît Farinas1, Marie Umber1, Matthieu Chabannes2, Nathalie

Laboureau2, Pierre Olivier Duroy2, Lydiane Bonheur1, Frédéric Salmon1, Christophe Jenny1,

Marie-Line Iskra-Caruana2 & Pierre-Yves Teycheney1Marie-Line Iskra-Caruana2 & Pierre-Yves Teycheney1

1 CIRAD, UMR AGAP, F-97130 Capesterre Belle-Eau, Guadeloupe, France2 CIRAD, UMR BGPI, F-34398 Montpellier Cedex 5, France

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Horizontal gene transfer is a very important process in eukaryotic evolution and

viruses are prominent DNA donors

• Plant genomes contain sequences of viruses with dsDNA

(Caulimoviridae) and ssDNA (Geminiviridae) genomes which have

• Animal genomes contain retroviruses and LTR retrotransposons

(Caulimoviridae) and ssDNA (Geminiviridae) genomes which have

no obligatory integration step in their replication cycle.

Teycheney P-Y & Geering ADW (2011) Endogenous viral sequences in plant genomes. Recent Advances in Plant Virology, eds Caranta C, Aranda MA, Tepfer M, & Lopez-

Moya JJ (Caister Academic Press), pp 347-366.

� Some endogenous Caulimoviridae sequences of banana, petunia

and Nicotiana edwardsonii are infectious and can lead to the

release of viral particles through stress-induced activation.

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Musa acuminata (A) Musa balbisiana (B)

• Fruit organoleptic qualities

• Disease resistance traits

• Rusticity and robustness

• Partial or total resistance to

biotic and abiotic stresses

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Interspecific hybrid

Infectious eBSV integratedinto the genome of the M.

balbisiana parent

Activating stress

Viral particles

© J

. Vo,

QA

AF

I

Dallot S., Acuna P., Rivera C., Ramirez P., Côte F., Lockhart B.E.L., Caruana M.L. (2001). Archives of virology, 146 : 2179-2190.

Lheureux F., Carreel F., Jenny C., Lockhart B.E.L., Iskra Caruana M.L. (2003). Theoretical and applied genetics, 106 : 594-598

Côte F, Galzi S., Folliot M., Lamagnère Y., Teycheney P.-Y., Iskra-Caruana M.-L. (2010). Mol. Plant Pathol. 11: 137–144

Interspecific hybrid(AAB / AAAB)

Known activating stresses:

• interspecific crosses

• temperature differences

• micropropagation

Viral particles

Risk of outbreak

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Yellow leaf streaksPseudostem

splitting

Abnormalinflorescence and bunch emergence

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

• Improved banana hybrid varieties with disease resistance traits are the key to

increased sustainability through the reduction of pesticide usage

• Breeding strategies rely on a narrow genetic basis, and only on 2 families of

progenitors : Musa acuminata (A) and Musa balbisiana (B)

AAw x AAcv colchicine

AAcv AAAAcv

• CIRAD’s breeding scheme:

AAcv AAAAcv

AAcv x AAcv

colchicine

AAcv x BBw ABcv AABBcv

AAcv x AAAAcv AAAcv

AAw x AAAAcv AAAcv

BBw x AAAAcv AABcv

AAcv x AABBcv AABcv

AAw x AABBcv AABcv

Tetraploid

parents

Triploid

hybrids

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Tetraploid parents

AAw x AAcv colchicine

AAcv AAAAcv

AAcv x AAcv

colchicine

AAcv x BBw ABcv AABBcv

Triploid hybrids

AAcv x AAAAcv AAAcv

AAw x AAAAcv AAAcv

BBw x AAAAcv AABcv

AAcv x AABBcv AABcv

AAw x AABBcv AABcv

• Only M. acuminata progenitors are used since 2001, which narrows down the

genetic basis available for breeding new varieties

• Research efforts have been focused on the creation of M. balbisiana ressources

devoid of infectious eBSVs for breeding purposes

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

eBSGFV-7(BAC 71C19)

eBSGFV-9(BAC 94I16)

13.3 kb

15.6 kb

eBSOlV -1 (BAC 310O7) 22.9 kb

23.2 kbeBSOlV-2 (BAC 73B22)

ORF1

ORF2

ORF3Viral genome

✖ 1 locus / di allélic

✖ 1 locus / mono alléliceBSImV(BAC 68C24)

15.8 kb

eBSMysV-1(BAC 29H14) 11.3 kb

eBSMysV-2(BAC 86I03)

12 kb

Infectious allele

Non infectious allele

✖ 1 locus / mono allélic

✖ 2 loci / mono-allélic

15.8 kb

Gayral P, Noa-Carrazana JC, Lescot M, Lheureux F, Lockhart BE, Matsumoto T, Piffanelli P, Iskra-Caruana M-L. (2008) J Virol. 82: 6697-710.

Iskra-Caruana M-L, Baurens FC, Gayral P, Chabannes M. (2010). Mol. Plant Micr. Interact 23: 1394-402

Gayral P, Blondin L, Guidolin O, Carreel F, Hippolyte I, Perrier X, Iskra-Caruana M-L (2010) J. Virol 84: 7346-59

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

�PCR Markers

OB

INO

L’E

WA

I

eBSOlV-1

eBSOlV-2

GO

LDF

ING

ER

eBSGFV-7

eBSGFV-9

eBSImV-1

IMO

VE

eBSImV-2

- Structures

- Integration

- Allèles

eBSMysV-1

IMO

VE

eBSImV-2

eBSMysV-2

MY

SO

RE

eBSV specific signature for each BSV species

Internal structure definition is ongoing

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

GF OL Im

PKW BBw GF7/GF9 OL1/OL2 Im

B. Honduras BBw GF7/GF9 OL1/OL2 n

Pisang Batu BBw GF7/GF9 OL1/OL2 Im

B. Cameroun BBw GF? OL? Im

Pisang Klutuk BBw GF7/GF9 OL1/OL2 Im

Porp (Popoulou) AABcv n OL? Im?

Langka AABcv n OL? n

Safet Velchi ABcv GF? OL1 n

Ney Poovan ABcv GF? OL1 n

Figue Pomme (Ekona) ABcv GF? OL1 n

Accessions with M. balbisiana genetic

background were screened by PCR, using

primer pairs differentiating infectious and

non infectious eBSVs

OL1, GF7, Im : infectious

OL2, GF9: non infectious

n : no eBSV

Figue Pomme (Ekona) ABcv GF? OL1 n

FlhorBan 902 AAAcv n n n

IDN 110T AAAA n n n

Kunnan D ABcv n OL? Im?

Kunnan T AABB n OL? Im?

FlhorBan 914 AABhyb GF9 OL2 Im

FlhorBan 910 AABhyb GF7 OL2 Im

French Clair AABcv GF7 OL1 n

Kelong Mekintu AABcv GF? OL1 n

Burro (CEMSA) ABBcv GF7/GF9 OL2/OL2 Im

Pelipita ABBcv GF7/GF9 OL1/OL2 Im

Bunga Oisan AABcv GF7 OL1 n

� Several accessions harbour both

infectious and non infectious eBSOLV

and eBSGFV alleles

� Modified alleles are present in some

cultivars (Cameroun, Kunnan, Kelong

Mekintu…)

� cv Honduras is free of eBSImV

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Breeding♂ X ♀

Seeds No seeds

Embryo rescue Failed

Plantlets

Plants weaning

eBSV signatures

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

B. Honduras BBw GF7/GF9 OL1/OL2 n B. Honduras BBw GF7/GF9 OL1/OL2 nX

• Progeny of 70 screened by PCR

OL1/OL2 OL1/OL1 OL2/OL2

GF7/GF9 30 13 7

Allelic signatures (%)

GF7/GF7 7 6 3

GF9/GF9 10 3 4

• eBSV signature results fit expected segregation ratios

• 4 % of plants are devoid of all infectious alleles

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

B. Cameroun BBw GF ? OL? ImB. Honduras BBw GF7/GF9 OL1/OL2 n X

• Progeny of 153 screened by PCR

OL1/OL2 OL1 OL2 ND

Allelic signatures (%)

GF7/GF9 7 13 7 2

GF7 3 14 4 2

GF9 1 14 14 4

ND 0 3 2 11

• 24 % harbour modified eBSOLV and eBSGFV alleles

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

B. Cameroun BBw GF ? OL? ImB. Honduras BBw GF7/GF9 OL1/OL2 n X

• Progeny of 153 screened by PCR

OL1/OL2 OL1 OL2 ND

GF7/GF9 - - - -

Allelic signatures (%) Imové -

GF7 - - - -

GF9 - - 1.3 1.3

ND - - - 7.2

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

• 1.3 % are devoid of all infectious alleles

����Molecular screening tools allow:

���� the study of eBSV alleles segregation

���� the search for individuals devoid of infectious

eBSV alleles

����Molecular screening tools allow:

���� the study of eBSV alleles segregation

���� the search for individuals devoid of infectious

eBSV alleles

M.balbisiana genitors devoid of infectious eBSV alleles

were created and are being used for breeding improved

banana interspecific hybrids

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

���� Unravel the structure of modified eBSV alleles

����Southern-blot

���� Sequencing

���� Unravel the structure of modified eBSV alleles

����Southern-blot

���� Sequencing

���� Study the infectious status of modified alleles���� Study the infectious status of modified alleles

���� Optimize molecular screening tools specific of modified

eBSV alleles

���� Optimize molecular screening tools specific of modified

eBSV alleles

���� Study the infectious status of modified alleles

���� CMR X IDN110 (AAB) progeny is being assessed

for the expression of infectious eBSVs

���� Study the infectious status of modified alleles

���� CMR X IDN110 (AAB) progeny is being assessed

for the expression of infectious eBSVs

14ème rencontres de virologie végétale, Aussois 13-17 January 2013

Lydiane BonheurIsabelle Acina

MamboleMarie Umber

Jean-Philippe

Pichaut

Pierre-Yves

Teycheney