Dedryver F, Jubier M F, Thouvenin J, Goyeau H
Institut national de la recherche agronomique (INRA), Station d'amélioration des plantes, Le Rheu, France.
Genome. 1996 Oct;39(5):830-5. doi: 10.1139/g96-105.
The aim of this study was to find molecular markers (RAPD and SCAR) for the wheat leaf rust resistance gene Lr24. A backcross line, RL 6064, possessing a single resistance gene to leaf rust (Lr24) and its recurrent parent 'Thatcher' were used to find RAPD markers linked to the Lr24 gene. Among 125 RAPD primers tested, only one (OP-H5) detected an additional band in the resistant line RL 6064. The genetic linkage of this molecular marker to Lr24 was tested on a segregating F2 population derived from a cross between the leaf rust resistant line RL 6064 and the susceptible line 'Chinese Spring'. This marker showed complete linkage to the Lr24 resistance gene. A more reliable and specific marker for this resistance gene was made by converting it into a sequence characterized amplified region (SCAR). The presence of a single amplification product allowed direct detection of the gene in the test tube by the addition of ethidium bromide. This SCAR marker linked to the leaf rust resistance gene Lr24 could be used easily in a practical breeding program.
本研究的目的是寻找小麦抗叶锈病基因Lr24的分子标记（随机扩增多态性DNA和序列特异性扩增区域）。利用一个对叶锈病具有单一抗性基因（Lr24）的回交系RL 6064及其轮回亲本“Thatcher”来寻找与Lr24基因连锁的随机扩增多态性DNA标记。在测试的125个随机扩增多态性DNA引物中，只有一个（OP-H5）在抗性系RL 6064中检测到一条额外的条带。在由抗叶锈病系RL 6064与感病系“中国春”杂交产生的分离F2群体上，对该分子标记与Lr24的遗传连锁进行了测试。该标记与Lr24抗性基因表现出完全连锁。通过将其转化为序列特异性扩增区域，获得了一个针对该抗性基因更可靠、更特异的标记。单一扩增产物的存在使得通过添加溴化乙锭可在试管中直接检测该基因。这个与小麦抗叶锈病基因Lr24连锁的序列特异性扩增区域标记可轻松应用于实际育种计划。
