Diseases
Pyricularia oryzae
Rice blast is a dangerous fungal disease of rice that affects all above-ground plant organs and can destroy up to 100% of the crop. The disease manifests in leaf, node, and panicle forms, causing necrosis and tissue death.
Mentioned in descriptions 470 varieties reference book.
Rice blast affects all above-ground organs of rice, including leaves, nodes, stems, and panicles, manifesting as characteristic grayish-green spots that eventually become silvery-white with a dark border. In the nodal form of the infection, stems turn black, while the panicle form results in spikelet sterility and the formation of shriveled grain, leading to critical crop losses during epiphytotic periods.
The development of the pathogen depends directly on environmental conditions, requiring temperatures in the range of 26–28 °C and high relative humidity above 89% for active spread, provided there is prolonged moisture on the leaf surface. The infection persists in plant debris and seeds, becoming active when favorable climatic factors occur.
Cultivar resistance is provided by specific R-genes that trigger plant defense responses through local tissue necrotization around the infection site. Breeding is focused on pyramiding multiple resistance genes; however, the effectiveness of protection may decrease due to the high adaptive variability of the fungus and the emergence of new virulent races in cultivation regions.
The evaluation of cultivar resistance in variety trials is conducted comprehensively using artificial infection backgrounds, molecular genetic markers for R-gene identification, and international disease severity scales. Environmental testing is of great importance, as it allows for the assessment of genotype reaction stability in various agrolandscape zones.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
Oryza sativa L. · Rice
Sardo Piemontese Sementi Soc. Coop. Società Agricola
Oryza sativa L. · Rice
CALIF.CO.RICE
Oryza sativa L. · Rice
ZELENSKIJ GRIGORIJ LEONIDOVICh / ZELENSKIJ ALEKSEJ GRIGOR'EVICh / TUMAN'YaN NATAL'Ya GEORGIEVNA / HARChENKO ELENA SEMENOVNA / HARITONOV EVGENIJ MIHAJLOVICh
Oryza sativa L. · Rice
NAIK Öntözési és Vízgazdálkodási Önálló Kutatási Oszály, Szarvas
Oryza sativa L. · Rice
S.I.S. SOCIETA' ITALIANA SEMENTI
Oryza sativa L. · Rice
Almo S.p.A.
Oryza sativa L. · Rice
S.I.S. SOCIETA' ITALIANA SEMENTI
Oryza sativa L. · Rice
S.I.S. SOCIETA' ITALIANA SEMENTI
Oryza sativa L. · Rice
LUGANO LEONARDO SRL
Oryza sativa L. · Rice
ENTE NAZIONALE RISI
Oryza sativa L. · Rice
SA.PI.SE SARDO PIEMONTESE SEMENTI
Oryza sativa L. · Rice
LUGANO LEONARDO SRL
Oryza sativa L. · Rice
Simonne dr. Kiss Ibolya / Pauk Janos / Bobvos Janosne / Budai Sandorne
Oryza sativa L. · Rice
HAO-DEMETER - Cereal Institute
Oryza sativa L. · Rice
GRASSI ALDO / RISO GALLO S.P.A. / VALLE AGRICOLA TARDITI E FERRANDO S.P.A.
Oryza sativa L. · Rice
SA.PI.SE SARDO PIEMONTESE SEMENTI
Oryza sativa L. · Rice
INSTITUTO HISPANICO DEL ARROZ, S.A. (HISPARROZ)
Oryza sativa L. · Rice
AL.MO S.P.A.
Oryza sativa L. · Rice
LUGANO LEONARDO SRL
Oryza sativa L. · Rice
LUGANO LEONARDO SRL
Oryza sativa L. · Rice
Sardo Piemontese Sementi Soc. Coop. Società Agricola
Oryza sativa L. · Rice
KOIPESOL SEMILLAS, S.A.
Oryza sativa L. · Rice
CAMARA ARROSSERA DEL MONTSIA, SCCL
Oryza sativa L. · Rice
SA.PI.SE SARDO PIEMONTESE SEMENTI