Phytopathology. 1998 Aug;88(8):856-61. doi: 10.1094/PHYTO.1998.88.8.856.
ABSTRACT To elucidate the specificity of prehaustorial resistance to inappropriate rust fungi, we studied two populations of recombinant inbred lines of barley that segregated for partial resistance (PR) to Puccinia hordei and for the resistance to the inappropriate rust species P. recondita f. sp. tritici and P. hordei-murini. PR to P. hordei is prehaustorial and nonhypersensitive, and its level can be assessed accurately by measuring the latent period of the fungus. The resistance to the inappropriate rust species is a combination of prehaustorial (nonhypersensitive) and posthaustorial (hypersensitive) mechanisms. The amount of nonhypersensitive, early abortion of P. recondita f. sp. tritici and P. hordei-murini sporelings reflects the degree of prehaustorial defense to the two inappropriate rust species. All lines showing a long latent period of P. hordei also had a relatively high level of early abortion of the growth of P. recondita f. sp. tritici and P. hordei-murini. This indicates that genes for PR to P. hordei are also effective against these two inappropriate rust species. The reverse was not necessarily true; some lines showing a high level of early abortion of P. recondita f. sp. tritici and P. hordei-murini had a low level of PR to P. hordei. Moreover, lines with a similar level of prehaustorial resistance to P. recondita f. sp. tritici could differ considerably in their prehaustorial resistance to P. hordei-murini. This indicates that genes for prehaustorial resistance may exhibit rust species specificity.
为了阐明对不适当锈菌的预小孢子体抗性的特异性，我们研究了两个大麦重组自交系群体，它们对 P. hordei 具有部分抗性（PR），并对不适当的锈菌物种 P. recondita f. sp. tritici 和 P. hordei-murini 具有抗性。对 P. hordei 的 PR 是预小孢子体的，非过敏性的，其水平可以通过测量真菌的潜伏期来准确评估。对不适当锈菌物种的抗性是预小孢子体（非过敏性）和后小孢子体（过敏性）机制的组合。非过敏性的、P. recondita f. sp. tritici 和 P. hordei-murini 孢子体早期流产的数量反映了对这两种不适当锈菌的预小孢子体防御程度。所有表现出 P. hordei 潜伏期较长的品系也具有相对较高水平的 P. recondita f. sp. tritici 和 P. hordei-murini 生长的早期流产。这表明，对 P. hordei 的 PR 基因也对这两种不适当的锈菌有效。反之则不然；一些表现出 P. recondita f. sp. tritici 和 P. hordei-murini 早期流产水平较高的品系对 P. hordei 的 PR 水平较低。此外，对 P. recondita f. sp. tritici 具有相似预小孢子体抗性水平的品系对 P. hordei-murini 的预小孢子体抗性可能有很大差异。这表明，预小孢子体抗性基因可能表现出锈菌物种特异性。
