Project description:Brown planthopper (BPH; Nilaparvata lugens) is a phloem feeding insect which is one of the most serious threats to rice crops in many countries throughout Asia. 1H NMR spectroscopy, combined with chemometrics, was used to analyze the polar metabolome from leaf extracts of Thai Jasmine rice (brown planthopper (BPH)-susceptible KD) and its BPH resistant isogenic lines (BPH-resistant IL7 and BPH-resistant+ IL308 varieties) with and without BPH infestation at various time points (days 1, 2, 3, 4 and 8). Physiological changes of the rice isogenic lines were different based on the quantitative trait loci of BPH resistance. Multivariate models were capable of distinguishing between the susceptible and the resistant rice varieties throughout the infestation. The concentration of 10 metabolites were significantly altered (p < 0.05) between the infested and the control groups of each examined rice variety. Metabolic pathway analysis suggested that BPH infestation could perturb transamination during the early stages of infestation (days 1–3) for all rice varieties. In addition, the IL7 and IL308 varieties responded earlier (day 3) than the KD variety (day 8) by perturbing amino acid metabolism, shikimate and gluconeogenesis pathways. By day 8 of the infestation, the KD cultivar responded by activating the amino acid-mediated-de novo pathway whereas the IL308 variety activated the purine and pyrimidine compound-mediated-salvage pathway for nucleotide biosynthesis. This study has identified, for the first time, several potential metabolic pathways for acclimatization and defense mechanisms against BPH infestation. These findings provide a valuable, first insight into BPH resistance mechanisms in Thai Jasmine rice.
Project description:Although Cochliobolus miyabeanus is an important fungal leaf pathogen on rice plants worldwide, it is largely neglected by molecular plant phytopathologists. To shed new light on the molecular and genetic basis of the rice – C. miyabeanus interaction, we compared the transcriptome of rice leaves 12h post inoculation to uninfected leaves. Even though usable sources of resistance against brown spot disease caused by C. miyabeanus are scarce, silicon application emerges as a sustainable protection strategy. Many articles report the beneficial effect of silicon on brown spot resistance. however the underlying mechanisms remain largely unclear. The influence of silicon application on the transcriptome of healthy and infected rice leaves 12hpi was compared as well in an attempt to disentangle the modulation of silicon-induced brown spot resistance.
Project description:Although Cochliobolus miyabeanus is an important fungal leaf pathogen on rice plants worldwide, it is largely neglected by molecular plant phytopathologists. To shed new light on the molecular and genetic basis of the rice M-bM-^@M-^S C. miyabeanus interaction, we compared the transcriptome of rice leaves 12h post inoculation to uninfected leaves. Even though usable sources of resistance against brown spot disease caused by C. miyabeanus are scarce, silicon application emerges as a sustainable protection strategy. Many articles report the beneficial effect of silicon on brown spot resistance. however the underlying mechanisms remain largely unclear. The influence of silicon application on the transcriptome of healthy and infected rice leaves 12hpi was compared as well in an attempt to disentangle the modulation of silicon-induced brown spot resistance. Comparison between C. miyabeanus- and mock-infected rice leaves 12h post inoculation. This study consist of a 2 x 2 factorial design (infected and non-infected; untreated and silicon-treated) in three biological replicates.
Project description:Infestation with white-backed planthopper (WBPH) to rice caused induced resistance to rice pathogens but brown planthopper (BPH) infestation induce weaker resistance to rice pathogens. We compared changes in gene expression in rice plants infested with WBPH and BPH to gain some insight into the WBPH-induced resistance to rice pathogens. An analysis, using microarrays, of gene expression in rice plants infested with these planthoppers revealed that WBPH infestation caused high induction of many defense-related genes including pathogenesis-related (PR) genes than BPH infestation. Furthermore, hydroperoxide lyase 2 (OsHPL2) which is an enzyme to produce C6 volatiles was induced by WBPH infestation, but not by BPH infestation. Keywords: response to herbivory; induced resistance
Project description:To explore the molecular mechanisms underlying the rice plant-mediated interaction between brown planthopper (BPH) and striped stem borer (SSB), gene expression changes in rice plant response to infestation by SSB, BPH or both and control were analyzed by RNA-seq.