title: Comparison of Sub1 markers and their combinations for submergence tolerance and analysis of adaptation strategies of rice in rainfed lowland ecology.
abstract: Ninety lowland rice cultivars of the eastern region of India were collected and screened for submergence and water logging tolerance and further used for validating the efficiency of molecular markers and their combinations for submergence tolerance. Submergence tolerance and elongation ability of the tested genotypes were measured in screening tanks along with tolerant and susceptible checks. The genotypes FR13A, Khoda, CR Dhan 300, Savitri Sub1, IR64 Sub1, IC-568009 and IC-568842 exhibited high submergence tolerance may be used as donor in the breeding program. Landrace 'Khoda' showed tolerance to submergence with moderate elongation ability for adaption. Boitalpakhia, Gayatri, Atiranga, Aghonibora, Chakaakhi, Moti, IC-567993 and IC-568921 possessed both characters of moderate elongation ability and moderate tolerance to submergence. Both of these traits are required for lowland varieties of eastern India to survive under flash flood and accumulated stagnant water conditions. RM8300, Sub1A203, AEX, Sub1BC2 and Sub1C173 were employed for molecular screening to identify the submergence-tolerant genotypes. Sub1A203 was capable of differentiating the tolerant and susceptible genotypes into groups. RM8300 and Sub1BC2 could also differentiate the genotypes with inclusion of some susceptible genotypes. The AEX and Sub1C173 marker could not show discrimination among the genotypes with respect to the traits. Using Sub1A203+Sub1BC2 was better amongst the combinations studied. The results of the study indicated a trend toward a negative association of Sub1BC2 with submergence tolerance while AEX and Sub1C marker did not show any significant association. The donors identified can be useful as parental lines while the molecular markers can be used for marker-assisted breeding work.
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India. Electronic address: pradhancrri@gmail.com.
authors: Sharat Kumar
authors: SK
authors: Pradhan
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.
authors: Saumya Ranjan
authors: SR
authors: Barik
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.
authors: Jayashree
authors: J
authors: Sahoo
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.
authors: Elssa
authors: E
authors: Pandit
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.
authors: Deepak Kumar
authors: DK
authors: Nayak
authors: National Bureau of Plant Genetic Resources, Base Center, Cuttack, Odisha, India.
authors: Dipti Ranjan
authors: DR
authors: Pani
authors: Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.
authors: Annamalai
authors: A
authors: Anandan
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000483:Alleles; D017753:Ecosystem; D055868:Floods; D017343:Genes, Plant; D005838:Genotype; D007101:Immersion; D007194:India; D005810:Multigene Family; D012275:Oryza / Q000235:genetics* / Q000502:physiology; D010641:Phenotype; D010802:Phylogeny; D000069600:Plant Breeding; D018520:Plant Shoots / Q000254:growth & development; D011891:Rain
keywords: Adaptation strategies; Elongation ability; Lowland rice; Molecular markers; Submergence tolerance