title: Salinity tolerance of japonica and indica rice (Oryza sativa L.) at the seedling stage.
abstract: In order to identify the degree of salinity tolerance of the indica and japonica rice groups, 10 varieties were tested under saline and non-saline conditions. Twelve-day-old seedlings were grown in normal culture solution, then initially salinized at an electrical conductivity (EC) of 6 dS/m for 4 days, and finally salinized at an EC of 12 dS/m for the next 14 days. The growth parameters, and Na and K absorption in the shoot were measured to characterize the tolerance level of the two rice groups. Reduction in all growth parameters of tolerant varieties was significantly lower in indica varieties than in japonica varieties. Tolerant indica varieties were good Na excluders, absorbed high amounts of K, and maintained a low Na/K ratio in the shoot. Tolerant japonica varieties also absorbed less Na but were not as good excluders as indica varieties. Shoot K concentration alone did not show any relationship to salinity tolerance. These results indicate that, for all parameters measured, the tolerance level of indica was higher than that of japonica.
authors.affiliation: Kyehwa substationSubstation, National Honam Agricultural Experiment Station, #2391 Changbukri, 579-820 Kyehwa-Myeon, Buan-Gun, Jeonbuk, Korea. klee@rda.go.kr
authors.forename: Kyu-Seong
authors.initials: KS
authors.lastname: Lee
authors.forename: Weon-Young
authors.initials: WY
authors.lastname: Choi
authors.forename: Jong-Cheol
authors.initials: JC
authors.lastname: Ko
authors.forename: Tae-Soo
authors.initials: TS
authors.lastname: Kim
authors.forename: Glenn B
authors.initials: GB
authors.lastname: Gregorio
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D004361:Drug Tolerance; D012275:Oryza / Q000187:drug effects* / Q000254:growth & development*; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development; D011188:Potassium / Q000494:pharmacology; D036226:Seedlings / Q000187:drug effects*; D012965:Sodium Chloride / Q000494:pharmacology*
chemical_list: D012965:Sodium Chloride; D011188:Potassium