Department of Plant Sciences, North Dakota State University, NDSU Department 7670, Fargo, ND 58108-6050, USA.
Genome. 2010 Aug;53(8):630-6. doi: 10.1139/g10-032.
Septoria speckled leaf blotch (SSLB), caused by Septoria passerinii, is one of the most important foliar diseases of barley (Hordeum vulgare L.) in North America. The primary problem caused by this disease is substantial yield loss. The objective of this study was to determine the chromosomal location of SSLB resistance genes in the barley accession PI 643302. A recombinant inbred line population was developed from the cross Zhenongda 7/PI 643302. PI 643302 is resistant while Zhenongda 7 is susceptible to SSLB. The population was phenotyped for SSLB resistance in five experiments in the greenhouse. A linkage map comprising 113 molecular markers was constructed and simplified composite interval mapping was performed. Two QTLs, designated QrSp-1H and QrSP-2H, were found. QrSp-1H was found on the short arm of chromosome 1H (1HS) in all five experiments and showed a large effect against SSLB. Based on the location of QrSp-1H, it is likely the SSLB resistance gene Rsp2. The QTL QrSp-2H mapped to the distal region on the long arm of chromosome 2H (2HL), had a smaller effect than QrSp-1H, and was also detected consistently in all five experiments. A QTL for SSLB resistance in the same region on chromosome 2H has not been reported previously in either cultivated or wild barley; thus, QrSp-2H is a new QTL for SSLB resistance in barley.
条斑叶枯病(SSLB)由叶点霉(Septoria passerinii)引起,是北美大麦(Hordeum vulgare L.)最重要的叶部病害之一。该病主要导致产量大幅损失。本研究旨在确定大麦品种 PI 643302 中 SSLB 抗性基因的染色体位置。利用珍龙大 7/PI 643302 杂交构建了重组自交系群体。PI 643302 对 SSLB 表现抗性,而珍龙大 7 表现感病。该群体在温室中的 5 个试验中对 SSLB 抗性进行了表型分析。构建了包含 113 个分子标记的连锁图谱,并进行了简化复合区间作图。发现了两个 QTL,分别命名为 QrSp-1H 和 QrSP-2H。QrSp-1H 在所有 5 个试验中均位于 1 号染色体短臂(1HS)上,对 SSLB 表现出较大的抗性。根据 QrSp-1H 的位置,它可能是 SSLB 抗性基因 Rsp2。QTL QrSp-2H 定位于 2 号染色体长臂(2HL)的远端,效应小于 QrSp-1H,并且在所有 5 个试验中均一致检测到。在栽培或野生大麦中,2H 染色体上 SSLB 抗性的同一区域以前没有报道过 QTL;因此,QrSp-2H 是大麦中 SSLB 抗性的一个新 QTL。