Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus.
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ABSTRACT:
SUBMITTER: Latorre SM
PROVIDER: S-EPMC10089362 | biostudies-literature | 2023 Apr
REPOSITORIES: biostudies-literature
Publications
Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus.
Latorre Sergio M SM Were Vincent M VM Foster Andrew J AJ Langner Thorsten T Malmgren Angus A Harant Adeline A Asuke Soichiro S Reyes-Avila Sarai S Gupta Dipali Rani DR Jensen Cassandra C Ma Weibin W Mahmud Nur Uddin NU Mehebub Md Shabab MS Mulenga Rabson M RM Muzahid Abu Naim Md ANM Paul Sanjoy Kumar SK Rabby S M Fajle SMF Rahat Abdullah Al Mahbub AAM Ryder Lauren L Shrestha Ram-Krishna RK Sichilima Suwilanji S Soanes Darren M DM Singh Pawan Kumar PK Bentley Alison R AR Saunders Diane G O DGO Tosa Yukio Y Croll Daniel D Lamour Kurt H KH Islam Tofazzal T Tembo Batiseba B Win Joe J Talbot Nicholas J NJ Burbano Hernán A HA Kamoun Sophien S
PLoS biology 20230411 4
Wheat, one of the most important food crops, is threatened by a blast disease pandemic. Here, we show that a clonal lineage of the wheat blast fungus recently spread to Asia and Africa following two independent introductions from South America. Through a combination of genome analyses and laboratory experiments, we show that the decade-old blast pandemic lineage can be controlled by the Rmg8 disease resistance gene and is sensitive to strobilurin fungicides. However, we also highlight the potent ...[more]
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Project description:BackgroundNitrogen often increases disease susceptibility, a phenomenon that can be observed under controlled conditions and called NIS, for Nitrogen-Induced Susceptibility. NIS has long been reported in the case of rice blast disease caused by the fungus Magnaporthe oryzae. We used an experimental system that does not strongly affect plant development to address the question of NIS polymorphism across rice diversity and further explored this phenomenon in wheat. We tested the two major types of resistance, namely quantitative/partial resistance and resistance driven by known resistance genes. Indeed there are conflicting reports on the effects of NIS on the first one and none on the last one. Finally, the genetics of NIS is not well documented and only few loci have been identified that may control this phenomenon.ResultsOur data indicate that NIS is a general phenomenon affecting resistance to blast fungus in these two cereals. We show that the capacity of rice to display NIS is highly polymorphic and does not correlate with difference related to indica/japonica sub-groups. We also tested the robustness of three different major resistance genes under high nitrogen. Nitrogen partially breaks down resistance triggered by the Pi1 gene. Cytological examination indicates that penetration rate is not affected by high nitrogen whereas growth of the fungus is increased inside the plant. Using the CSSL mapping population between Nipponbare and Kasalath, we identified a Kasalath locus on chromosome 1, called NIS1, which dominantly increases susceptibility under high nitrogen. We discuss the possible relationships between Nitrogen Use Efficiency (NUE), disease resistance regulation and NIS.ConclusionsThis work provides evidences that robust forms of partial resistance exist across diversity and can be easily identified with our protocol. This work also suggests that under certain environmental circumstances, complete resistance may breakdown, irrelevantly of the capacity of the fungus to mutate. These aspects should be considered while breeding for robust forms of resistance to blast disease.
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