An acylsugar-deficientNicotiana benthamianastrain for aphid and whitefly research

Abstract

Nicotiana benthamiana is used extensively as a platform for transient gene expression and as a model system for studying plant-virus interactions. However, many tobacco-feeding insects, e.g. Myzus persicae (green peach aphids) and Bemisia tabaci (whiteflies), grow poorly on N. benthamiana, limiting its utility for research on plant-insect interactions. Using CRISPR/Cas9, we generated knockout mutations in two N. benthamiana acylsugar acyltransferase genes, ASAT1 and ASAT2, which contribute to the biosynthesis of insect-deterrent acylsucroses. Whereas ASAT1 mutations reduced the abundance of two predominant acylsucroses, ASAT2 mutations caused almost complete depletion of foliar acylsucroses. Both M. persicae and B. tabaci survived and reproduced significantly better on asat2 mutant plants than on wildtype N. benthamiana. Furthermore, ASAT1 and ASAT2 mutations reduced the water content and increased the temperature of leaves, indicating that foliar acylsucroses can protect against desiccation. Improved aphid and whitefly performance on ASAT2 mutants will make it possible to use the efficient transient overexpression and gene expression silencing systems that are available for N. benthamiana to study plant-insect interactions. Additionally, the absence of acylsugars in ASAT2 mutant lines will simplify transient expression assays for the functional analysis of acylsugar biosynthesis genes from other Solanaceae.

Comparative transcriptome analysis reveals key candidate genes mediating ovarian development in Spodoptera frugiperda fed on two host plants

“…Development of resistant cultivars against FAW attacks would serve as an effective complementary approach in IPM to reduce its damage levels ( Jallow et al, 2004 ). Aryl sugars on the surface of leaves are a powerful barrier against some insects, as shown by the ability of Bemisia tabaci (whiteflies) to reproduce on Nicotiana benthamiana with an acylsugar acyltransferase knockout but not on wildtype plants ( Feng et al, 2021 ). However, the contributions of host plants to the reproductive system in S. frugiperda are not clear.…”