Earthworms are vital to soil ecosystems and organic waste recycling, but present identification challenges due to morphological variability and limitations in distinguishing juvenile or degraded specimens. Traditional identification methods relying on adult morphology are labour-intensive and restricted in scope. Molecular techniques, including the use of mitochondrial and ribosomal genes (e.g., COI, 16S rRNA), offer improved species resolution. This study focuses on optimising RNA extraction from juvenile P. excavatus using TRIZOL reagent. The protocol involves tissue homogenisation, phase separation, RNA precipitation, washing, and resuspension. Modifications, such as cold processing and additional washing steps, enhanced RNA quality. Purity was confirmed through agarose gel electrophoresis and UV spectrophotometry, yielding intact RNA bands and ideal absorbance ratios. The optimised method provides a reliable approach for obtaining high-quality RNA from earthworms, facilitating molecular identification and ecological studies.
Earthworms, Identification, Total RNA extraction, Trizol reagent
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