Rapid Detection of Nosema bombycis in Sericulture: A Review on Nucleic Acid-Based Lateral Flow Assays

Abstract

Pebrine, a destructive disease in silkworms caused by the microsporidian Nosema bombycis, continues to pose a significant threat to global sericulture. Traditional detection methods, such as female moth microscopy (FMM), are often time-consuming, labor-intensive, and prone to inaccuracies, particularly in detecting low-level infections. To address these limitations, nucleic acid-based lateral flow assays (NALFAs) have emerged as a promising alternative, offering rapid, accurate, and field-deployable diagnostic capabilities. This review explores the development and application of NALFA strips for pebrine detection, detailing their underlying principles, technical configuration, and diagnostic performance. NALFAs combine PCR amplification with lateral flow immunoassay principles, enabling the sensitive and specific detection of N. bombycis DNA, with detection limit as low as 10² spores per 50 eggs. These assays offer significant advantages, including high accuracy, portability, speed, and cost-effectiveness. Nonetheless, challenges remain, such as limited multiplexing capacity, reliance on modified DNA, and the absence of integrated signal amplification. Future improvements may involve the incorporation of automated micro fluidic systems to streamline sample preparation, amplification, and detection. Additionally, developing multiplex diagnostics for simultaneous detection of multiple silkworm pathogens could enhance disease management. Overall, NALFAs represent a significant breakthrough in sericulture disease diagnostics, offering an efficient tool for early pebrine detection and contributing to a more resilient and sustainable silk industry.