Development and application of gene-based markers for the major rice QTL Phosphorus uptake 1
Development and application of gene-based markers for the major rice QTL Phosphorus uptake 1
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水稻吸磷主要QTL基因标记的开发及应用1
DOI：
10.1007/s00122-009-1235-7
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发表时间：
2010-04-01
影响因子：
5.4
通讯作者：
Heuer, Sigrid
中科院分区：
文献类型：
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作者：
Chin, Joong Hyoun;Lu, Xiaochun;Heuer, Sigrid
标记辅助育种是一种非常有用的育种工具，但由于缺乏不同遗传背景和理想分子标记对数量性状位点（qtl）影响的信息，标记辅助育种的潜力还远远不够。在此，我们报告了水稻主要QTL磷素吸收1 （Pup1）的验证和应用的一些初步步骤，该QTL赋予水稻（Oryza sativa L.）对磷(P)缺乏的耐受性。根据最近获得的耐受性供体品种Kasalath的Pup1基因组序列，设计了标记，以(1)在Nipponbare参考基因组中部分保守的假定基因和(2)位于Nipponbare不存在的大插入缺失（INDEL）区域的Kasalath特异性基因为目标。在159个不同的水稻品种中测试这些标记，证实了它们在不同基因型中的诊断价值，并表明Pup1存在于50%以上适应压力易感环境的水稻品种中，而在分析的灌溉/低地品种中仅检测到约10%。此外，在超过80%的抗旱水稻品种中检测到Pup1位点，这表明育种者在不知情的情况下选择了Pup1。水培试验揭示了旱地品种和灌溉品种对缺磷反应的基因型差异，但证实了根系伸长与Pup1无关。对比Pup1近等基因系（NILs）随后在两种不同缺磷土壤和环境中生长。在施用有氧生长条件下，与不含Pup1位点的姐妹系相比，含Pup1位点的NILs在缺磷条件下保持了较高的粒重（-1）。总的来说，这些数据提供了证据，证明Pup1在缺磷和/或干旱易发环境和不同遗传背景下具有提高产量的潜力。
Marker-assisted breeding is a very useful tool for breeders but still lags behind its potential because information on the effect of quantitative trait loci (QTLs) in different genetic backgrounds and ideal molecular markers are unavailable. Here, we report on some first steps toward the validation and application of the major rice QTL Phosphate uptake 1 (Pup1) that confers tolerance of phosphorus (P) deficiency in rice (Oryza sativa L.). Based on the Pup1 genomic sequence of the tolerant donor variety Kasalath that recently became available, markers were designed that target (1) putative genes that are partially conserved in the Nipponbare reference genome and (2) Kasalath-specific genes that are located in a large insertion-deletion (INDEL) region that is absent in Nipponbare. Testing these markers in 159 diverse rice accessions confirmed their diagnostic value across genotypes and showed that Pup1 is present in more than 50% of rice accessions adapted to stress-prone environments, whereas it was detected in only about 10% of the analyzed irrigated/lowland varieties. Furthermore, the Pup1 locus was detected in more than 80% of the analyzed drought-tolerant rice breeding lines, suggesting that breeders are unknowingly selecting for Pup1. A hydroponics experiment revealed genotypic differences in the response to P deficiency between upland and irrigated varieties but confirmed that root elongation is independent of Pup1. Contrasting Pup1 near-isogenic lines (NILs) were subsequently grown in two different P-deficient soils and environments. Under the applied aerobic growth conditions, NILs with the Pup1 locus maintained significantly higher grain weight plant(-1) under P deprivation in comparison with intolerant sister lines without Pup1. Overall, the data provide evidence that Pup1 has the potential to improve yield in P-deficient and/or drought-prone environments and in diverse genetic backgrounds.