Characterization of components of partial resistance, Rps2, and root resistance to Phytophthora sojae in soybean
Characterization of components of partial resistance, Rps2, and root resistance to Phytophthora sojae in soybean
复制标题
DOI：
10.1094/phyto-97-5-0655
复制
发表时间：
2007-05-01
期刊：
影响因子：
3.2
通讯作者：
Dorrance, Anne E.
中科院分区：
文献类型：
--
作者：
Mideros, Santiago;Nita, Mizuho;Dorrance, Anne E.
大豆疫霉（Phytophthora sojae）引起的大豆疫霉根腐病是严重限制美国大豆生产的病害。大豆中对大豆疫霉的部分抗性对病原体的所有小种都有效，并且是一种不完全抗性形式，其中接种后根的定殖水平降低。其他形式的不完全抗性包括单显性基因Rps 2和里普利根抗性，这两种抗性都是种族特异性的。为了区分部分抗性和其他类型的不完全抗性，在8个大豆基因型中测定了接种两个大豆疫霉菌分离物的病斑长度、卵孢子数量和感染频率。与部分抗性基因型Conrad相比，Rps 2和根抗性基因型具有显著较低的卵孢子产生和感染频率，而根抗性基因型也具有显著较小的病斑长度。然而，根据对这些组件的评价，Jack中的高水平部分电阻与L76-1988中的Rps 2无法区分。Ripley和Rps 2在L76-1988中的根抗性对本研究中测量的所有组分具有相似的响应。在Conrad、威廉姆斯、Jack和General中表达的部分抗性由在根中相互作用以防御大豆疫霉的各种组分组成，并且在每个基因型中发现每个组分的不同水平。然而，通过Ripley和Rps 2在L76-1988中的单基因表达的不完全抗性的形式，不能根据病斑长度、卵孢子产生和感染频率与高水平的部分抗性区分开。
Phytophthora root and stem rot of soybeans caused by Phytophthora sojae is a serious limitation to soybean production in the United States. Partial resistance to P. sojae in soybeans is effective against all the races of the pathogen and is a form of incomplete resistance in which the level of colonization of the root is reduced following inoculation. Other forms of incomplete resistance include the single dominant gene Rps2 and Ripley's root resistance, which are both race-specific. To differentiate partial resistance from the other types of incomplete resistance, the components lesion length, numbers of oospores, and infection frequency were measured in eight soybean genotypes inoculated with two P. sojae isolates. The Rps2 and root-resistant genotypes had significantly lower oospore production and infection frequency compared with the partially resistant genotype Conrad, while the root-resistant genotype also had significantly smaller lesion lengths. However, the high levels of partial resistance in Jack were indistinguishable from Rps2 in L76-1988, based on the evaluation of these components. Root resistance in Ripley and Rps2 in L76-1988 had similar responses for all components measured in this study. Partial resistance expressed in Conrad, Williams, Jack, and General was comprised of various components that interact for defense against P. sojae in the roots, and different levels of each component were found in each of the genotypes. However, forms of incomplete resistance expressed via single genes in Ripley and Rps2 in L76-1988, could not be distinguished from high levels of partial resistance based on lesion length, oospore production, and infection frequency.