From 2003 to 2005, in pot and field experiments, rice response to salinity stress of 15 rice varieties was studied at germination and young seedling stages using salt affected soils collected from rice production area...From 2003 to 2005, in pot and field experiments, rice response to salinity stress of 15 rice varieties was studied at germination and young seedling stages using salt affected soils collected from rice production areas in the Office du Niger zone of Mali. The rice varieties were composed of 10 rice genotypes from the breeding program of Mali and five from West African Rice Development Association (WARDA) program (Saint Louis, Senegal). Soil samples were collected from the visually affected soils which were characterized by the appearance of white or black efflorescence on the soil surface. In pot experiments, the genotypes were allowed to germinate in both affected soil types (white efflorescence and black efflorescence) and salt effects on plant seedling growth were observed. Results showed that all varieties were significantly sensitive to salinity stress based on germination, young seedling shoot and root dry weights. Among the rice varieties, the most salt tolerant variety was BG90-2 (a high yielding genotype from the Institut d'Economie Rurale (IER) breeding program) while the most sensitive variety was Telimani (also from the breeding program of IER). All other varieties were intermediary between these two genotypes. A three year field experiment conducted in a highly affected area near Niono confirmed the results of the pot experiment. The relatively salt tolerant genotypes were found in both Malian (BG90-2, Kogoni91-1, SK51-5-2) and WARDA (Was30-11-1-1-4-6-1B) rice breeding programs.展开更多
文摘From 2003 to 2005, in pot and field experiments, rice response to salinity stress of 15 rice varieties was studied at germination and young seedling stages using salt affected soils collected from rice production areas in the Office du Niger zone of Mali. The rice varieties were composed of 10 rice genotypes from the breeding program of Mali and five from West African Rice Development Association (WARDA) program (Saint Louis, Senegal). Soil samples were collected from the visually affected soils which were characterized by the appearance of white or black efflorescence on the soil surface. In pot experiments, the genotypes were allowed to germinate in both affected soil types (white efflorescence and black efflorescence) and salt effects on plant seedling growth were observed. Results showed that all varieties were significantly sensitive to salinity stress based on germination, young seedling shoot and root dry weights. Among the rice varieties, the most salt tolerant variety was BG90-2 (a high yielding genotype from the Institut d'Economie Rurale (IER) breeding program) while the most sensitive variety was Telimani (also from the breeding program of IER). All other varieties were intermediary between these two genotypes. A three year field experiment conducted in a highly affected area near Niono confirmed the results of the pot experiment. The relatively salt tolerant genotypes were found in both Malian (BG90-2, Kogoni91-1, SK51-5-2) and WARDA (Was30-11-1-1-4-6-1B) rice breeding programs.