Elliott P E, Lewis R S, Shew H D, Gutierrez W A, Nicholson J S
Department of Crop Science.
Department of Plant Pathology.
Plant Dis. 2008 Mar;92(3):425-430. doi: 10.1094/PDIS-92-3-0425.
Stem rot and target spot of tobacco, caused by Rhizoctonia solani and its teleomorph Thanatephorus cucumeris, respectively, can cause serious problems in production of tobacco (Nicotiana tabacum) seedlings. Previous screens for genetic resistance in tobacco have been limited. The objective of this study was to evaluate 97 genotypes composing several classes of tobacco and related Nicotiana spp. for seedling resistance to stem rot and target spot. Significant differences in disease incidence initially were observed among the genotypes for both stem rot and target spot; however, resistance to target spot was not observed when disease pressure was high. Partial resistance to stem rot was observed in several genotypes in repeated tests. These accessions may be useful as a source of resistance to R. solani in future breeding efforts.
烟草立枯病和靶斑病分别由立枯丝核菌及其有性型瓜亡革菌引起，会给烟草（烟草属）幼苗生产带来严重问题。此前对烟草遗传抗性的筛选有限。本研究的目的是评估97个基因型，这些基因型由几类烟草及相关烟草属物种组成，以确定其幼苗对立枯病和靶斑病的抗性。最初在基因型之间观察到立枯病和靶斑病的发病率存在显著差异；然而，当病害压力较大时未观察到对靶斑病的抗性。在重复试验中，在几个基因型中观察到对立枯病的部分抗性。这些种质在未来的育种工作中可能作为对立枯丝核菌抗性的来源。
