Maintaining elevated Fe2+ concentration in solution culture for the development of a rapid and repeatable screening technique for iron toxicity tolerance in rice (Oryza sativa L.)
Issue Date
11-2013
Abstract
Background and aims: Iron toxicity decreases rice (Oryza sativa) grain yield especially in acid soils after flooding. Our aim was to establish a high-throughput screening technique using nutrient solution culture for identifying Fe-toxicity-tolerant genotypes. Methods: Varying levels of Fe, pH, and chelators in Yoshida nutrient solution culture were tested to maintain sufficient Fe2+ concentration over time to optimize the severity of Fe toxicity stress for distinguishing between a tolerant (Azucena) and sensitive (IR64) genotype. The optimized solution was tested on 20 diverse genotypes in the greenhouse, with measurement of leaf bronzing scores and plant growth characteristics at the seedling stage. The same 20 genotypes were grown to maturity in a field with natural Fe toxicity stress, with measurement of seedling-stage leaf bronzing scores and grain yield to determine their inter-relationship. Results: Optimized nutrient solution conditions were 300 mg L-1 Fe supplied as Fe2+ at pH 4.0 with a 1:2 molar ratio of Fe:EDTA, which maintained sufficient Fe2+ stress over 5 days. The highest correlation of nutrient solution phenotypic data with field grain yield was found with leaf bronzing scores at 4 weeks, with a Pearson r of 0.628 for simple association and a Spearman corrected r of 0.610 for rank association (P < 0.01) using 20 diverse rice genotypes with proven Fe toxicity tolerance reaction. The Leaf bronzing scores at 4 weeks in nutrient culture solution were also found highly correlated with LBS under natural field stress after 8 weeks that had highest correlation with grain yield under stress. Conclusion: This culture solution-based standardized screening technique can be used in plant breeding programs as a high-throughput technique to identify genotypes tolerant to Fe toxicity. © 2013 Springer Science+Business Media Dordrecht.
Source or Periodical Title
Plant and Soil
ISSN
0032-079X
Volume
372
Issue
1-2
Page
253-264
Document Type
Article
Physical Description
illustrations, tables, graphs
Language
English
Subject
EDTA, Fe concentration 2+, Iron toxicity, pH, Rice, Screening technique
Recommended Citation
Elec, Venus & Quimio, Celsa & Mendoza, Rhulyx & Sajise, Andres & Beebout, Sarah & Gregorio, Glenn & Singh, Rakesh. (2013). Maintaining elevated Fe2+ concentration in solution culture for the development of a rapid and repeatable screening technique for iron toxicity tolerance in rice (Oryza sativa L.). Plant and Soil. 372 (1-2), 253-264. doi:10.1007/s11104-013-1739-4.
Identifier
doi:10.1007/s11104-013-1739-4.
Digital Copy
yes