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Figure 4 | Plant Methods

Figure 4

From: Rapid metabolic profiling of Nicotiana tabacum defence responses against Phytophthora nicotianae using direct infrared laser desorption ionization mass spectrometry and principal component analysis

Figure 4

Principal component analysis of the IR-LDI-oTOF MS spectra. PC1 vs. PC2 score plot of an unsupervised PCA of the positive ion mode IR-LDI mass spectra acquired from differently treated samples of Nicotiana tabacum (cv. SNN). Based on their distribution with respect to the PC2-axis, the samples can, qualitatively, be grouped into three clusters: (I) untreated samples (blank near a placebo zone, BP); (II) "stressed" samples from local water infiltration (placebo near blank or infection zone; PB, PI); and (III) "stressed" samples from infection (IP, IB, BI). The line labeled as "Thr" separates samples that do not undergo HR (-HR) from those that undergo HR (+HR) (i.e. top right = high cell death, bottom left = low cell death). The line f(PC1,PC2) is displayed as the perpendicular line to "Thr". The "stress status" (BRI value, displayed in Figure 5) for each sample is obtained from the projection of any point to f(PC1,PC2).

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Plant Methods

ISSN: 1746-4811