Exploration of genetic diversity of earthworms in degraded landscapes in Lagos, Nigeria using random amplified polymorphic DNA (RAPD) markers

Abstract

Earthworms are crucial for maintaining soil ecosystems and their functions, such as improving soil structure, nutrient cycling, and decomposition of organic matter. This study aimed to assess the genetic diversity of earthworm species in three specific sites: Iwaya, Makoko, and UNILAG areas of Lagos. Random Amplified Polymorphic DNA (RAPD) analysis was employed to detect genetic variations rapidly. Thirty earthworms were collected from three dumpsites, and DNA extraction was performed following the Sambrook and Russel protocol. Four RAPD primers were utilized, resulting in the amplification of forty products. Among the primers, OPA13 produced the highest number of amplified products (22), indicating the presence of highly variable genomic regions. The UPGMA Cluster analysis revealed two distinct yet related clusters among the earthworm populations, suggesting genetic differentiation influenced by local conditions and geographic barriers. Principal Component Analysis (PCA) identified PC1 and PC2 as major contributors to the observed genetic variance using the four RAPD primers. This study unveiled a high level of genetic variation among the examined earthworms, indicating the presence of diverse genetic traits. These findings contribute to our understanding of the adaptability and resilience of earthworms to environmental changes, thereby supporting the development of effective strategies for ecological restoration and management.