Panicle bacterial blight in Colombia: gknowing the enemy as a first step in finding 

control alternatives

Gloria Mosquera, Plant PathologistRice Plant Pathology Programgy g

International Center for Tropical Agriculture, CIATCali, Colombia

Presentation Outline

•General Background

St di di l i h• Studies on disease cycle in greenhouse

•Identification of causal agent on field samples

•Disease distribution and variability

•Current activities and future workCurrent activities and future work

General  Background

Causal Agent Burkholderia glumae Ag

Symptoms:Grain discoloration, infertilityStraight panicleStraight panicle 

Sheath rot in seedlings (Mainly in nurseries, not frequent in field)

Reported in Colombia in 1987 (Zaigler and Alvarez)

Seed‐Born disease but…N l i f d d b i d f di d lNot only infected seeds seem to be  required for disease development

Greenhouse observations

Field conditions

Greenhouse observations

3 S fl3. Symptoms on flowers(bacteria concentration 

increased) 

Plants without symptoms not even in flowers

2. Epiphytic phase(low bacteria concentration)

Infected 

1.  Bacteria seed‐transmitted seeds

Disease widely distributed in Colombia

Depto. Localidad

Identificación por PCR1

B. glumae

2 (%) 3 B. gladioli2

(%) 3

distributed in Colombia glumae

Antioquia 1 2(1) 50 2(0) 0

Atlántico 1 1(0) 0 1(0) 0B gladioli has been also Bolívar 2 4(3) 75 4(0) 0

Casanare 1 1(0) 0 1(0) 0

Cesar  3 17(12) 71 11(6) 55

B. gladioli has been also detected. First report in Colombia.(Poster by P. Fory)

CIAT 1 157(59) 38 68(10) 15

Córdoba 4 11(8) 73 11(0) 0

Huila 3 7(2) 29 6(1) 17

( y y)

Huila 3 7(2) 29 6(1) 17

Meta 6 40(19) 48 26(3) 12

Santander 1 2(2) 100 1(0) 0

Sucre 1 5(2) 40 5(0) 0

Tolima 13 94(58) 62 50(8) 16

V. del Cauca

2 3(1) 33 3(1) 33

Total  39 344(167) 49 189(29) 15

B. glumae vs B gladioli

B.glumae more aggressive

B. gladioli less aggressiveB. gladioli less aggressive but similar symptoms

B. glumae is widely distributed in Colombia  Cepa Registro Departame

ntoMunicipio Variedad Pigmentación

but how diverse is the population?(Poster by D. Bravo)

nto1 3161‐2 Sucre San Marcos Fedearroz 2000 Pigmentada

2 3193‐No 4 Córdoba La victoria Fedearroz 2000 Pigmentada3 3193‐No 5 Córdoba La victoria Fedearroz 2000 No Pigmentada4 3196‐10 Meta Santa Rosa Oryzica Llanos 5 No Pigmentada5 3200‐12 Córdoba La victoria Fedearroz 2000 Pigmentada6 3252‐ 8 Antioquia Nechi Desconocida Pigmentada7 3455 1 Bolívar San Jacinto Fedearroz 733 Pigmentada

Location where disease has  an effect  on yield 

7 3455‐1 Bolívar San Jacinto Fedearroz 733 Pigmentada8 3459‐4 Bolívar María la baja Fedearro473 Pigmentada9 3643‐2 Córdoba Lorica    Arroz rojo Pigmentada10 3646‐1 Córdoba Lorica    Fedearroz 2000 Pigmentada11 3650‐3 Córdoba Lorica    Fedearroz 733 Pigmentada12 3651‐1 Córdoba Montería 71 Pigmentada13 3651‐4 Córdoba Montería Fedearroz 733 No Pigmentada

14 3656‐1 Córdoba Montería Mezc. Fedearroz Pigmentada15 3659‐1 Córdoba Montería Fedearroz mejor. Pigmentada16 3718‐2 Tolima Ambalema  Or‐370 Pigmentada17 3722‐1 Tolima Guamo CimarronBarinas Pigmentada18 3807‐9 Tolima Espinal Orizya 1 Pigmentada19 3809‐2 Tolima Guamo Fedearroz 60 Pigmentada20 3818‐8 Tolima Venadillo Clearfield‐370 Pigmentada20 3818 8 Tolima Venadillo Clearfield 370 Pigmentada21 3825‐14 Tolima Venadillo Fedearroz 60 Pigmentada22 3847B‐10(S) Meta Santa Rosa Fedearroz 174 Pigmentada23 3848‐5(S) Meta Santa Rosa Fedearroz 134 Pigmentada24 3851‐4 Meta Santa Rosa 71 Pigmentada25 3853‐4 Tolima Progreso  CimarronBarinas Pigmentada26 3854‐2 Tolima Prado CimarronBarinas Pigmentada27 3855‐4 Tolima Progreso Coprosem 304 Pigmentada27 3855‐4 Tolima Progreso  Coprosem 304 Pigmentada28 3856‐5 Tolima Parificación CimarronBarinas Pigmentada29 3858‐2 Tolima Parificación Coprosem 304 Pigmentada30 3859‐5 Tolima Santa Inés CimarronBarinas No Pigmentada31 3861‐2 Meta Santa Rosa RD‐FLAR 18 Pigmentada32 3862‐3 Meta Santa Rosa RD‐FLAR 28 Pigmentada33 3864‐4 Meta Santa Rosa RD‐FLAR 68 Pigmentada34 3866B‐10 Santander Cúcuta Fedearroz 733 Pigmentada34 3866B 10 Santander Cúcuta Fedearroz 733 Pigmentada35 3880‐7 Cesar Tamalameque Fedearroz 2000 Pigmentada36 3883‐8 Meta Villavicencio Improarroz 1550 Pigmentada37 3889A‐2 Tolima Armero Panorama 20‐08 Pigmentada38 3890‐4  Tolima Saldaña Coprosem 1 Pigmentada39 3891A‐1 Tolima Ibagué Aceituno  Pigmentada

B. glumae population is highly diverse5 main genetic clusters correlated with geographical

BOX-PCR profiles

N th

Eastern plains

5 main genetic clusters correlated with geographical location

North

Center

MetaMeta

Mixed

Adjusting a system for strain aggressiveness/host response evaluationaggressiveness/host response evaluation

B glumae WaterB. glumae Water

Panicle inoculation

Colombia XXI highly susceptible

Non pigmented strains as referenceEvaluation after 14 days of inoculation

Establishment of evaluation system

•Colombia XXI was susceptible to most of the strains

•Pathogenic strains> 50% damage

•Low pathogenic <20% damage

The same system is being used to screen germplasm looking for tolerance sources

Strains representing all genetic clusters are being included in this evaluation

Tolerant materials (hot spot) will be challenged with multiple location strains.

OUR TEAM

Gustavo PradoPaola ForyPaola ForyGirlena AricapaLiliana BolañosCarlos PradoLuis Rosero

Fomer membersDaniela BravoDaniela Bravo

OUR COLLABORATORS

FEDEARROZFLARMADRMADR