Website: https://vjfc.nifc.gov.vn/
Website: https://vjfc.nifc.gov.vn/
Spodoptera litura nucleopolyhedrovirus (SpltNPV) is an insect virus belonging to the family Baculoviridae, with high specificity to the tobacco cutworm (Spodoptera litura), and is used in biological plant protection products. This study aimed to develop and validate a method for the detection and quantification of SpltNPV using real-time PCR. The method was developed based on amplification of the lef-8 gene, which encodes a late expression factor that is highly conserved and specific to SpltNPV. The amplified target gene fragment was confirmed by Sanger sequencing to verify the reference strain, showing ≥ 99% similarity to the published lef-8 sequence of SpltNPV. The real-time PCR method showed 100% accuracy, specificity, and sensitivity, with both the limit of detection and the limit of quantification reaching 10² OBs/g, and no amplification was observed in the negative control samples. The Ct-log₁₀ viral DNA concentration standard curve demonstrated good linear correlation (R² = 0.995). The repeatability and reproducibility parameters met the acceptance criteria according to CEN/TS 17329-1:2021 and ISO 22118:2011. The results indicate that the proposed method has high reliability and stability and is suitable for the detection, quantification, and quality control of SpltNPV in biological plant protection products.
Spodoptera litura nucleopolyhedrovirus; real-time PCR; SpltNP; plant protection product.
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