Host: The Japanese Society of Plant Physiologists
Pages 0292
It is well known that low nitrogen supply causes stimulation of root elongation in rice. Chromosome segment substitution lines (CSSLs) developed between Koshihikari and Kasalath were employed for mapping QTLs controlling root length under various NH4+ concentrations. One of QTLs stimulated the root length by Kasalath allele was detected on long arm of chromosome 8 under 5 μM NH4+. When Koshihikari and SL-225, a CSSL substituted Kasalath segment on this QTL region, were hydroponically grown with 5-1000 μM NH4+, the root length of SL-225 was significantly stimulated under all concentration tested. Content of absorbed nitrogen in the SL-225 plants was significantly decreased under 50 μM NH4+. To isolate a target gene from the QTL region, BC1F2 and F3 progenies derived from SL-225 were tested for the stimulation of root elongation grown with 5 μM NH4+. As a result, target QTL was delimited at the 7 cM region.
