Authors: Akifumi Shimizu Seiji Yanagihara Shinji Kawasaki Hiroshi Ikehashi
Publish Date: 2004/09/16
Volume: 109, Issue: 7, Pages: 1361-1368
Abstract
A significant level of root elongation was induced in rice Oryza sativa grown under phosphorusdeficient conditions The root elongation clearly varied among a total of 62 varieties screened under two different phosphorus levels Two contrasting varieties ‘Gimbozu’ with a low elongating response and ‘Kasalath’ with a high elongating response were chosen and crossed to produce a hybrid population for QTL analyses QTLs for the phosphorus deficiencyinduced root elongation were detected by two linkage maps ie one with 82 F3 families constructed by 97 simple sequence repeat SSR and sequencetag site markers and another with 97 F8 lines by 790 amplified fragment length polymorphism and SSR markers A single QTL for the elongation response was detected on chromosome 6 with a LOD score of 45 in both maps and explained about 20 of total phenotypic variance In addition this QTL itself or a region tightly linked with it partly explained an ability to reduce accumulation of excess iron in the shoots The identified QTL will be useful to improve rice varieties against a complex nutritional disorder caused by phosphorus deficiency and iron toxicityFigure S2 A An example layout of a stripplot design with five varieties V1 V2 V3 V4 V5 as horizontal treatments to one row plot consisting seven plants as a bulk and two phosphorus rates P1 P2 as vertical treatments in duplicates Both treatments are independently randomized in each replication and horizontal strips V1V5 are continuous across vertical treatments P1 P2 B A layout in of a splitplot design with five varieties as subplot and two phosphorus rates as main plot was also indicated as a referenceFigure S3 Linkage maps derived from ‘Gimbozu’ and ‘Kasalath’ Left side is a highdensity linkage map of 97 F8 lines consisting of 727 AFLP and 63 SSR and right side is a linkage map of 82 F3 families consisting of 71 SSR 15 STS and one morphological marker A gap in F3 map was indicated by a dotted line For AFLP markers in F8 map ‘Gimbozu’associate and ‘Kasalath’ associate dominant markers and codominant markers are indicated by A red and B blue and H green respectively SSR markers are indicated as RM black and consistent RM markers between F8 and F3 map were linked with a broken line
Keywords: