Genetic variation for virulence in Septoria tritici

• Main Authors: Kema G.H.J, Silfhout C.H. van, Annone J.G, Sayoud R, Ginkel M. van, De Bree J
• Format: Book
• Language: English
• Published: 1995
• Subjects: descendance; enfermedades de las plantas; genetic variation; genotipos; genotype; genotypes; hosts; hote; huespedes; inoculacion; inoculation; inoculation methods; maladie des plantes; mycosphaerella graminicola; pathogenese; pathogenesis; patogenesis; plant diseases; progenie; progeny; triticum aestivum; variacion genetica; variation genetique
• ISBN: 9789686923490; 9686923497

La variacion de la virulencia de S. tritici fue estudiada en 78 aislamientos de 16 paises. Se estimaron la necrosis y el numero de picnidios. Los aislamientos derivados de trigo harinero fueron estudiados separadamente en su mayoria sobre hospedantes de trigo harinero, mientras que los aislamientos derivados de trigo duro fueron principalmente inoculados sobre trigos duros. La interaccion variedad x aislamiento fue significativa dentro de ambos experimentos. Se marcaron diferencias tambien en el orden de los cultivares, lo que podria indicar que esta operando un sistema de gene por gene. Una agrupacion gerarquica de aglomerados proporciono mas evidencia de que los aislamientos de S.tritici son especializados, ya sea sobre trigo harinero o trigo duro. En un experimento comparativo en plantula (invernadero) y planta adulta (campo) 14 y tres aislamientos de Holanda se inocularon respectivamente sobre 22 genotipos de trigos. La interaccion aislamiento por cultivar fue significativa, lo que indica diferencias en virulencia. Sobre tres cultivares la respuesta de campo medida en necrosis fue significativamente diferente de aquella medida como numero de picnidios. Los mecanismos envueltos podrian ser diferentes. La correlacion entre plantula y planta adulta fue significativa solo para uno de los aislamientos. Variation for virulence was studied on almost 78 Septoria tritici isolates from 16 countries. Necrosis and number of pycnidia were estimated. The bread wheat derived isolates were studied separately mostly on bread wheat hosts, while the durum wheat derived isolates were mainly inoculated on durum wheats. The cultivar x isolate interaction was significant in both experiments. Differences in cultivar ranking were also noted, which would indicate a gene-for-gene system. Agglomerative hierarchical clustering provided further evidence that S. tritici isolates are specialized on their bread wheat or durum wheat host. In a comparative seedling (greenhouse) and adult plant (field) experiment 14 and 3 Dutch isolates respectively were inoculated on 22 wheats. Isolate x cultivar interaction was significant, indicating differences in virulence. On three cultivars, the field response as measured in necrosis was significantly different from that measured as number of pycnidia. Mechanisms involved could be different. The correlation between seedling and adult plant data was significant for only one of the isolates.