Novel Insights Into the Early Stages of Ratoon Stunting Disease of Sugarcane Inferred from Transcript and Protein Analysis

Abstract

Despite of the importance of ratoon stunting disease, little is known on the responses of sugarcane to its causal agent, the vascular bacterial endophyte Leifsonia xyli subsp. xyli. The transcriptome and proteome of young plants of a susceptible cultivar with no symptoms of stunting but with relative low and high bacterial titers were compared at 30 and 60 days after inoculation. Increased bacterial titers were associated with alterations in the expression of 267 cDNAs and in the abundance of 150 proteins involved in plant growth, hormone metabolism, signal transduction and defense responses. Some alterations are predicted to benefit the pathogen, such as the up-regulation of genes involved in the synthesis of methionine. Also, genes and proteins of the cell division cycle were all down-regulated in plants with higher titers at both times. It is hypothesized that the negative effects on cell division related to increased bacterial titers is cumulative over time and its modulation by other host and environmental factors results in the stunting symptom.

Comparative Transcriptome Profiling of Resistant and Susceptible Sugarcane Cultivars in Response to Infection by Xanthomonas albilineans

“…avenae causing red stripe disease [22] and Leifsonia xyli subsp. xyli (Lxx) causing ratoon stunting disease [23,24]. These findings showed that many common genes and the pathways they are involved with constitute important clues for further investigation of sugarcane-pathogen interactions.…”

“…Plant hormones such as JA, ethylene, and indole acetic acid (IAA) are involved in defense against pathogens [41,42]. Genes related to auxin, abscisic acid (ABA), ethylene, and JA signaling pathways have also been associated with infection of sugarcane by various pathogens [18,22,23]. To regulate plant growth and development, auxin can induce the expression of gene groups such as the Aux/IAA family, the GH3 family and the small auxin-up RNA (SAUR) family [43].…”

“…Sugarcane's response to this disease included genes involved in auxin influx/efflux, auxin-amino acid hydrolase, and auxin responsive proteins such as Aux/IAA, SAUR, and auxin-induced β-glucosidase [44]. Additionally, genes related to the metabolism of auxin were all up-regulated in susceptible variety inoculated by Lxx mostly at 60 days [23] and similar hormonal changes were observed in sugarcane trigged by Lxx infection [45]. The auxin responsive GH3 gene also plays important roles in plant defense responses in Arabidopsis and rice [41].…”

Identification of resistant sugarcane genotypes to ratoon stunt disease by Fourier-transform infrared analysis

“…In agreement, Cia et al (2018) Another intriguing finding relates to peaks previously correlated to alpha helix amide I protein and polyamines in studies related to plant cell wall compounds since the same wavenumbers were observed in our study (Sene et al 1994;Kärkönen and Kuchitsu 2014;Romero et al 2018). In the first trial, susceptible genotypes showed higher peaks for alpha helix amide I protein and lower for four different bands correlated to polyamines.…”

“…In addition, in plants with higher bacterial titers most genes involved in the control of the cellcycle were downregulated, which could also explain the major symptom of the disease (Cia et al 2018). At the biochemical level, recent study developed by our group defined some metabolites as candidate's resistance biomarkers to Lxx .…”