Leaf Bacteriome in Sugar Beet Shows Differential Response against Beet curly top virus during Resistant and Susceptible Interactions

Abstract

Beet curly top virus (BCTV) significantly reduces sugar beet yield in semi-arid production areas. Genetic resistance to BCTV is limited; therefore, identification of additional resistance-associated factors is highly desired. Using 16S rRNA sequencing and BCTV resistant (R) genotypes (KDH13, KDH4-9) along with a susceptible (S) genotype (KDH19-17), we investigated leaf bacteriome changes during BCTV post inoculation (pi). At day 6 (~6-week-old plants), Cyanobacteria were predominant (~90%); whereas, at week 4 (~10-week-old plants) Firmicutes (11–66%), Bacteroidetes (17–26%), and Verrucomicrobia (12–29%) were predominant phyla and genotype dependent. Both Bacteroidetes and Verrucomicrobia, increased post infection only in the R lines. The bacterial genera Brevibacillus increased at 6 dpi, and Akkermansia and Bacteroides at 4 wkpi in the R lines. Linear discriminant analysis effect size (LEfSe) identified potential biomarkers in the R vs. S lines. Functional profiling revealed bacterial enrichment associated with the TCA cycle, polyisoprenoid, and L-methionine biosynthesis pathways only in KDH4-9 at 6 dpi. At 4 wkpi, bacteria associated with tryptophan and palmitate biosynthesis in the R lines, and uridine monophosphate, phosphatidyl glycerol, and phospholipid biosynthesis in the S line, were enriched. Future characterization of bacterial genera with antiviral properties will help establish their use as biocontrol agents/biomarkers against BCTV.

Genotype by Environment Interaction Effects on the Crop of Sugar Beet (Beta vulgaris L.) Using Multivariate Analysis

“…These results indicated that PC1 can be referred to as the high-root weight component and the basis in the weighting of selection genotypes, thus PC1 is important to increase sugar beet productivity in the three environments. Alami et al [23], Islam et al [24], Majumdar et al [26] and Mehareb et al [40] have previously revealed similar results for the first two main PCs.…”

“…[22], Alami et al [23], Islam et al [24], Kleuker and Hoffmann [25] and Majumdar et al [26]. The aim of this work was to study the effect of environment on genotypes of sugar beet under various regions in Egypt, and evaluate the magnitude of genotype x environment interaction using the multivariate methods, thus discovering the most stable sugar beet genotype and determining associations for the studied traits in ten sugar beet genotypes under three different environments.…”

Culture-Dependent and Metabarcoding Characterization of the Sugar Beet (Beta vulgaris L.) Microbiome for High-Yield Isolation of Bacteria with Plant Growth-Promoting Traits

“…Results showed that most plant-beneficial bacteria detected on various plant-based media could not be detected by metabarcoding. The microbiome of the sugar beet has previously been analyzed using metabarcoding from various aspects: seasonal shifts in the lateral root microbiome [ 6 ], spatiotemporal changes in endophytic bacterial diversity [ 34 ], the rhizobiome of the sugar beet under different fertilizer systems [ 35 ], the leaf bacteriome in relation to the susceptibility of the sugar beet to beet curly top virus [ 36 ], and Cercospora leaf spot disease [ 37 ]. In this study, the microbiome of the sugar beet was investigated in two plant parts, the root and the leaf, and compared in different plant development stages (May, July, and October).…”

Advances and New Perspectives in Plant-Microbe Interactions

“…Regarding pathogens and pests in plant biotic interactions, four of the papers in this issue focus on how plants recognize (shape the associated microbiomes) and defend against pathogens. Majumdar et al (2022a) [ 10 ] uncover, for the first time, the sugar beet leaf bacteriome response against beet curly top virus (BCTV). Using BCTV-susceptible and—resistant sugar beet genotypes and beet leafhopper (BLH)—mediated natural BCTV infection, their study highlights the restructuring of the bacterial microbiome in the leaves following BCTV infection, and their differential regulation in both sugar beet genotypes in a temporal manner of infection stage.…”