Garcia Alexandre, Calvo Eberson Sanches, de Souza Kiihl Romeu Afonso, Harada Arlindo, Hiromoto Dario Minoru, Vieira Luiz Gonzaga Esteves
State University of Londrina (UEL), Rod. Celso Garcia Cid Km 380, Cx. Postal 6001, CEP 86051-990 Londrina, PR, Brazil.
Theor Appl Genet. 2008 Aug;117(4):545-53. doi: 10.1007/s00122-008-0798-z. Epub 2008 May 28.
Soybean production in South and North America has recently been threatened by the widespread dissemination of soybean rust (SBR) caused by the fungus Phakopsora pachyrhizi. Currently, chemical spray containing fungicides is the only effective method to control the disease. This strategy increases production costs and exposes the environment to higher levels of fungicides. As a first step towards the development of SBR resistant cultivars, we studied the genetic basis of SBR resistance in five F2 populations derived from crossing the Brazilian-adapted susceptible cultivar CD 208 to each of five different plant introductions (PI 200487, PI 200526, PI 230970, PI 459025, PI 471904) carrying SBR-resistant genes (Rpp). Molecular mapping of SBR-resistance genes was performed in three of these PIs (PI 459025, PI 200526, PI 471904), and also in two other PIs (PI 200456 and 224270). The strategy mapped two genes present in PI 230970 and PI 459025, the original sources of Rpp2 and Rpp4, to linkage groups (LG) J and G, respectively. A new SBR resistance locus, rpp5 was mapped in the LG-N. Together, the genetic and molecular analysis suggested multiple alleles or closely linked genes that govern SBR resistance in soybean.
南美洲和北美洲的大豆生产最近受到由真菌豆薯层锈菌引起的大豆锈病（SBR）广泛传播的威胁。目前，含有杀菌剂的化学喷雾是控制该病的唯一有效方法。这种策略增加了生产成本，并使环境暴露于更高水平的杀菌剂中。作为培育抗SBR品种的第一步，我们研究了五个F2群体中SBR抗性的遗传基础，这些群体来自巴西适应型感病品种CD 208与五个不同的携带SBR抗性基因（Rpp）的植物引进品种（PI 200487、PI 200526、PI 230970、PI 459025、PI 471904）的杂交。在其中三个引进品种（PI 459025、PI 200526、PI 471904）以及另外两个引进品种（PI 200456和224270）中进行了SBR抗性基因的分子定位。该策略将PI 230970和PI 459025（Rpp2和Rpp4的原始来源）中存在的两个基因分别定位到连锁群（LG）J和G上。一个新的SBR抗性位点rpp5被定位到LG-N上。遗传和分子分析共同表明，多个等位基因或紧密连锁的基因控制着大豆对SBR的抗性。
