OsGA20ox1, a candidate gene for a major QTL controlling seedling vigor in rice
OsGA20ox1, a candidate gene for a major QTL controlling seedling vigor in rice
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DOI：
10.1007/s00122-012-1857-z
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发表时间：
2012-08-01
影响因子：
5.4
通讯作者：
Terauchi, Ryohei
中科院分区：
文献类型：
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作者：
Abe, Akira;Takagi, Hiroki;Terauchi, Ryohei
秧苗活力是决定直播稻稳定立木的主要因素之一。在温带地区利用250个粳稻品种挂桥和东汉沙里杂交获得的重组自交系（RIL），对影响秧苗活力的数量性状位点（QTL）进行了定位。播种后14天测得的苗高分别为20.3和29.4厘米的挂桥和敦翰沙里。对于RILs，高度范围为14.1 - 31.7 cm。检测到4个与苗高相关的QTL。位于第3染色体长臂上的主效QTL qPHS 3 -2对表型变异的贡献率为26.2%。使用近等基因系（NILs）的后代回交引入一个染色体片段携带这个主要QTL到一个精英品种Iwatekko，我们精细映射qPHS 3 -2的两个标记，ID_CAPS_01和RM 16227之间的81 kb的间隔。在此区域内，我们鉴定了与赤霉素（GA）生物合成相关的基因OsGA 20 ox 1。GA 20 ox 1在东旱沙梨和近等基因系中的相对表达量均高于岩茶。与此同时，与Iwatekko中检测到的水平相比，Donghan Shali和NIL中的内源活性GA的量更高。这些结果表明OsGA 20 ox 1是控制水稻幼苗活力的主效QTL的强候选基因。
Seedling vigor is among the major determinants of stable stand establishment in direct-seeded rice (Oryza sativa L.) in temperate regions. Quantitative trait loci (QTL) for seedling vigor were identified using 250 recombinant inbred lines (RILs) derived from a cross between two japonica rice cultivars Kakehashi and Dunghan Shali. Seedling heights measured at 14 days after sowing were 20.3 and 29.4 cm for Kakehashi and Dunghan Shali, respectively. For the RILs, the height ranged from 14.1 to 31.7 cm. Four putative QTLs associated with seedling height were detected. qPHS3-2, the major QTL that was located on the long arm of chromosome 3, accounted for 26.2 % of the phenotypic variance. Using progeny of the near isogenic lines (NILs) produced by the backcross introduction of a chromosome segment carrying this major QTL into an elite cultivar Iwatekko, we fine-mapped qPHS3-2 to a 81-kb interval between two markers, ID_CAPS_01 and RM16227. Within this mapped region, we identified the gene OsGA20ox1, which is related to gibberellin (GA) biosynthesis. The relative expression levels of GA20ox1 in seedlings of Dunghan Shali and NILs were higher than that of Iwatekko. Concomitantly, the amount of endogenous active GA was higher in Dunghan Shali and the NILs compared to the level detected in Iwatekko. These results indicate that OsGA20ox1 is a strong candidate gene for major QTL controlling seedling vigor in rice.