International Workshop on Facilitating International Research

Collaboration on Transboundary Plant Pests

Wheat Blast

• Caused by Magnaporthe oryzae pathotype triticum (MoT)

• Wheat blast is seedborne & airborne disease • Resistance sources identified but limited knowledge

on its genetics available• MoT population is very diverse, exhibits many pathotypes

that could cross-infect different hosts and overcome resistance

• Fungicide schemes are partially effective under low to medium WB pressure. Pathogen has ability to develop fungicide resistance

• Can attack any aerial parts of wheat plant but disease is seen mainly on spikes

Wheat Blast-Introduction

StemSeedling leaf

Bleached spike

Eye shaped lesion on leaf

Awn & glumes

Grains shriveled, poorly developed

Wheat Blast-Symptoms

Wheat Blast• Discovered in Parana State of Brazil

in 1985 and since then spreading to an area of about 3.0 m ha causing losses of 10-100% depending on years, genotypes, planting date and environment.

• Reported in C & S Brazil, low lying areas of Santa Cruz region of Bolivia, S and SE Paraguay, and NE Argentina.

• Observed in Bangladesh in 2016

BRAZIL

0500 mi

500 km

BOLIVIA

ARGENTINA

PR

1996

2005 2007

1985

1990

WB in Bangladesh2015-16: 1st report of WB occurrence in Bangladesh in seven districts. 25-30% loss 2016-17: WB spread to fourmore districts. 5-10% loss2017-18: Unfavorable conditions for development of WB. Spread to additional fivedistricts. 3-5% loss2018-19: WB development limited due to unfavorable conditions. Spread to four more districts. 1-2% loss

Ex-Ante Analysis: Impact of Wheat Blast in India, Pakistan and BangladeshCountry Wheat

area(m. hac)

Area WB vulnerable(m. hac)

Production(m. ton)

Per capita use (kg/year)

1961 2013

Losses due to WB (10%) (0000- ton)

Economic loss (m. USD)

Bangladesh 0.43 0.28 1.25 8.6 17.5 85.14 12.69

India 30.90 6.57 95.85 27.9 60.6 1640.89 244.49

Pakistan 9.52 0.14 26.96 90.0 113.6 45.32 6.75

TOTAL 40.85 6.99 123.01 - - 1771.35 263.83

Bangladesh is net importer of wheatIndia & Pakistan are self sufficient with limited export (IND) or import (PAK)

1.32 Billion USD if loss due to WB is 50%

Mottaleb et al. PLoS One 13(5): e0197555

2009 Photo: von Tiedemann & Duveiller

Oryza pathotype (MoO) Triticum pathotype (MoT)

Lolium pathotype (MoL)

The Mo pathotypes differ by avirulence genes that block infection of other grass species

Magnaporthe oryzae Pathotypes Host Specific

Malaker et al, 2016, Plant Disease 100:2330; Mark Farman et al

Distance Tree of Bangladeshi Isolates of MoT

Bangladeshi Isolates

Resistance Genes ReferenceRmg1 (Rwt4) Takabayashi et al., 2002

Rmg1 (Rwt4) Hau et al., 2007Rmg2 and Rmg3 (7A and 6B) Zhan et al., 2008

Rmg4 and Rmg5 (4A and 6D) Nga et al., 2009

Rmg6 (1D) Vy et al., 2014RmgTd (t) Cumagun et al., 2014Rmg7 (2A in T. dicoccum) Tagle et al., 2015Rmg8 (2B) Anh et al., 2015RmgGR119 (Tentative) Wang et al. 20182NS translocation (Ae. ventricosa) Cruz et al., 2016

Wheat Blast Resistance Genes

GEORREFERENCIA

Latitude: 18.20 SLongitude: 63.56 WAltitude: 1494 maslCrop Cycle: Dec.-April

Latitude : 17.13 SLongitude: 62.54 WAltitude: 267 maslCrop Cycle: May-August

Precision Phenotyping Platform for Wheat Blast in Bolivia and Bangladesh

Okinawa

Quirusillas

Latitude: 23.13 NLongitude: 89.20 EAltitude: 7 maslCrop Cycle: Dec.-April

Jeshore

Precision Phenotyping Platform at Jashore

PPP at Quirusillas

PPP at Okinawa

Artificial Inoculation

Top Performers on Wheat Blast Resistance Across Environments

• Non-2NS lines were more susceptible and unstable across environments• 2NS carriers usually showed good and stable resistance

Power of International Collaboration

BARI Gom 33: Blast resistant & biofortifiedPhoto source: BARI

Vulnerable Areas in Bangladesh, India and

Pakistan

•Bangladesh scientists observed a resistant CIMMYT breeding line in ‘NVR Trial’

•WB resistance confirmed in USDA-ARS greenhouse and field trials in Bolivia

• Resistant variety ‘BARI Gom 33’ released in 2017: 2NS Resistance, Yield = 5 t/ha, + 7 ppm Zn advantage

Projected losses:1.32 billion USD in

epidemic years

Combating WB in Bangladesh

Inter-Continental Blast Collaboration

Bolivia Bangladesh

Borlaug 100 in 2016 as INIAF Tropical

Kachu/Solala in 2017 as BARI Gom 33

Kachu/Solala in 2019 as INIAF-Okinawa

Borlaug 100 in 2019 as BWMRI XXX

Wheat Holiday or Discouraging Wheat ProductionBangladesh Government discouraged wheat production in wheat blast affected areas of 201662,763 hectare in 201614,238 hectare in 2017India has wheat holiday in 5 km boarder area adjoining Western BangladeshIn India: Two districts Nadia and Murshidabad- there is wheat holiday

Economically viable options: Onion, Garlic, Potato, Maize and LentilDue to perishability, market, storage & infrastructure issues onion, garlic and potato may not be options

Wheat Blast Collaborators For Success

International Funds Research Partner

Wheat Blast: Unveiling epidemiological aspects

J. M. Fernandes1, K. S. Pawan2

1) Embrapa, Brazil; 2) CIMMYT, Mexico

Ken Young, Jeevan Khurana, Zhou Yilin, Fan Jieru, Clovis Douanla-Meli, Luca Riccioni, Yokio Tosa, Hirokazu Handa, Masaya Fujita, Yoshimichi Fukuta, Takashi Hirata, Suat Kaymak, Kerry Pedley and Robert Park

November 27-29, 2019, International Workshop on Facilitating International ResearchCollaboration on Transboundary Plant Pests. Tuksuba, Japan

What triggers an outbreak?

Where all the inoculum is coming from?

21

Pizolotto et al, 2018

Seed Transmission

• Infection is superficial• Low-Moderate transmission rate (10-20%)• Easily controlled by fungicides

Important for disease introduction

Echinochloa spp.Brachiaria spp.

Chloris distichophylla

Eleusine indica

Cenchrus echinatus

Elionurus candidus

wheat field

Digitaria spp.

Our approach

Symptomatic samples Isolation

Storage DNA extraction

CH7-BAC9 MoT3

Sequencing

Po pathotypes Triticum pathotype

Pyricularia(176)

Pyricularia oryzae(106)

P. oryzae pathotypes (69)

P. oryzae Triticum pathotype (37)

Pyricularia spp.(70)

Main results

Perennial Forage Crops: Brachiaria spp.

As primeiras lavouras de trigo implantadas nas áreas recém desbravadas do norte do Paraná com cultivares de porte

alto,

desenvolvidos no RS, apresentavam elevados níveis de perdas por acamamento. Para enfrentar esse problema, no

início

dos anos 70, optou-se pela introdução de germoplasma desenvolvido pelo– 131 CIMMYT, localizado no México.

Lotes significativos de sementes de Sonora 63, Sonora 64, INIA F 66, Jupateco F 73, Anahuac F 75 e outros

cultivares

semelhantes, foram introduzidos≈220 million heads

≈70% Nelore

The irregular frequency of outbreaks makes it hard to understand or predict the precise conditions for disease development

Eleusine indica

April 25, 2018

February 20, 2018

This illustrate what we mean by inoculum build up

The most important biotic constrain for wheat production for the Cerrado region of Brazil

4.5 Million hectares > 800 m of altitude

Pasinato, 2017

An intercontinental collaboration for disease disruptive data science

1985

2016

EMBRAPA-UPF (Brazil): 30+ years of experience with wheat blast monitoring, image recognition (artificial intelligence and machine learning), and app-based disease monitoring systems.

CIMMYT (Bangladesh): Global leader in wheat blast pathology with established track-record of cross-country surveillance programs and innovative science solutions.

> 20 MILLION

FARMERS

AT RISK

7 MILLION HECTARES

VULNERABLE; $1.77 MILLION

IN LOSSES PER YEAR POSSIBLE

WITH JUST 10% INFECTION

Established mobile and web platform for disease monitoringhttp://picawheatfield.org/

Weather-based risk forecasting model

Mobile phone field monitoring app

Citizen science: Real-time disease incidence

mapping

Heat maps to assess risk of

outbreaks

Fully coupled DSSAT-Nwheat/Disease models

Fully coupled DSSAT-Nwheat/wheat blast models

Fully coupled DSSAT-Nwheat/wheat blast models

2015 2016

Universidade de Passo FundoWillingthon Pavan

Carlos HolbigFelipe Vargas

Carlos PizolottoThiago BertonFábio Oliveira

Universidade Federal de ViçosaEmerson del Ponte

João Ascari

CIMMYTTimothy J. Krupnik

Pawan Singh

EmbrapaMárcio Nicolau Vanoli Fronza

Kansas State UniversityBarbara Valent

Jim StackErick de WolfChristian Cruz

University of KentuckyMark Farman

BiotrigoAndré Rosa

Paulo Kühnem

EpamigMaurício Coelho