Tetraose steroidal glycoalkaloids from potato provide resistance againstAlternaria solaniand Colorado potato beetle

Abstract

Plants with innate disease and pest resistance can contribute to more sustainable agriculture. Resistance breeding typically relies on the use of immune receptors or impaired susceptibility genes, but these come with challenges in terms of strength, durability or pleotropic effects. Natural defence compounds from plants are not considered in breeding, because biosynthesis of these compounds is a complex trait and proof of their role in resistance is often indirect. Here, we identified a wild relative of potato, Solanum commersonii, that provides us with unique insight in the role of glycoalkaloids in plant immunity. We cloned two atypical resistance genes that can provide complete resistance to Alternaria solani and Colorado potato beetle through the production of tetraose steroidal glycoalkaloids. Moreover, we show that these compounds are active against a wide variety of fungi. This research highlights the potential of using natural defence compounds produced by plants to protect them against pests and diseases.

Untargeted metabolomics reveals PTI‐associated metabolites

“…They found that lysophosphatidylcholine (LPC17:1) was accumulating on the surface of the wild potato, but not on S. bulbocastanum and in vitro assays revealed an antifungal activity against P. infestans (Gorzolka et al, 2021). SM associated with resistance were also the focus of another recent study in Solanum commersonii ; the differences between accessions that are resistant against A. solani and those that are susceptible can be explained by differences in glycosyltransferase genes that are involved in the production of tetraose steroidal glycoalkaloids that are toxic to A. solani (Wolters et al, 2023). In this study, we investigate the potential SMs that may play a role in the resistance of cultivated tomato plants against A. alternata .…”

Untargeted metabolomics reveals PTI-associated metabolites in tomato

“…They found that lysophosphatidylcholine (LPC17:1) was accumulating on the surface of the wild potato, but not on S. bulbocastanum and in vitro assays revealed an antifungal activity against P. infestans (Gorzolka et al, 2021). Secondary metabolites associated with recentance were also focus of another recent study in S. commersonii; the differences between accessions that are resistant against A. solani and those that are susceptible, can be explained by differences in glycosyltransferase genes that are involved in the production of tetraose steroidal glycoalkaloids that are toxic to A. solani (Wolters et al, 2023). In this study, we investigate the potential SMs that may play a role in the resistance of cultivated tomato plants against A. alternata.…”

Alternaria diseases on potato and tomato

“…are capable of (Hoyos et al, 2023), implying the existence of more SGAs and other compounds in MeJA-treated leaf extracts. Wild solanaceous plants are a veritable wellspring of antifungal SGAs, with broad-spectrum antifungal tetraose SGAs conferring immunity to Solanum commersonii from EBDC (Wolters et al, 2023). This EBDC resistance locus has been successfully backcrossed into potato cultivars and confers broad resistance, also to other pathogens (Wolters et al, 2021), but the effects of tetraose SGAs to the environment and human ingestion are currently unknown.…”