A Comparative Study of Three Detection Techniques for Leifsonia xyli Subsp. xyli, the Causal Pathogen of Sugarcane Ratoon Stunting Disease

Figure 4

Sensitivity assay of Lxx82F/Lxx22R primers set for Lxx-infected sugarcane juice DNA and Lxx-pMD18-T plasmid using RT-qPCR. (a) Melt-curve analysis; (b) standard curve; (c) amplification plot of serial dilutions of DNA sample extracted from Lxx-infected sugarcane juice; templates 1-3 were 10-fold serial dilutions of Lxx-infected sugarcane juice DNA (10⁰ to 10⁻², 4.0 ng/μL to 0.04 ng/μL); and (d) amplification plot of serial dilutions of Lxx-pMD18-T plasmid; templates 1-9 were 10-fold serial dilutions of Lxx-pMD18-T plasmid (10⁰ to 10⁻⁸, 1.0 ng/μL to 1.0 × 10⁻⁸ ng/μL). The red arrow points to the limiting detection concentration.

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