Mini Review: Potential Applications of Non-host Resistance for Crop Improvement

Abstract

Plant breeding for disease resistance is crucial to sustain global crop production. For decades, plant breeders and researchers have extensively used host plant resistance genes (R-genes) to develop disease resistant cultivars. However, the general instability of R-genes in crop cultivars when challenged with diverse pathogen populations emphasizes the need for more stable means of resistance. Alternatively, non-host resistance is recognized as the most durable, broad-spectrum form of resistance against the majority of potential pathogens in plants and has gained great attention as an alternative target for managing resistance. While transgenic approaches have been utilized to transfer non-host resistance to host species, conventional breeding applications have been more elusive. Nevertheless, avenues for discovery and deployment of genetic loci for non-host resistance via hybridization are increasingly abundant, particularly when transferring genes among closely related species. In this mini review, we discuss current and developing applications of non-host resistance for crop improvement with a focus on the overlap between host and non-host mechanisms and the potential impacts of new technology.

Non-host Resistance Induced by the Xanthomonas Effector XopQ Is Widespread within the Genus Nicotiana and Functionally Depends on EDS1

“…Plant NHR reactions vary from symptomless reactions to HR (Uma et al, 2011). Non-host plants represent an excellent repertoire of R genes and potentially novel resistance mechanisms, which can be employed to generate resistant crop plants (Bent, 2016; Lee et al, 2016). …”

Molecular breeding technologies and strategies for rust resistance in wheat (Triticum aestivum) for sustained food security

“…Rice is known to possess NHR against all rust pathogens whereas other cereals are rust susceptible. Because of the durable and broad-spectrum nature of this resistance, NHR has great potential in resistance breeding in crop plants (Lee et al, 2016). NHR has been known for a long time; however, exploitation of NHR in resistance breeding programmes has not been possible because of lack of knowledge of molecular mechanisms involved in NHR and reproductive barriers between species.…”

Resistance to viruses of potato: current status and prospects

“…Однако NHR против близкородственных видов патогенов может включать механизмы, сходные с механизмами специфической устойчивости. В последнее время растет число данных, свидетельствующих, что кластеризованные гены R, особенно гены, кодирующие белки NBLRR типа, могут приобретать «нехозяйский» статус, т. е. наблюдается опосредованная этими генами устойчивость в отношении неродственных патогенов (Gill et al, 2015;Lee et al, 2016).…”