Unveiling the Bacterial Endosymbionts in Mustard Aphid, Lipaphis erysimi pseudobrassicae (Davis): An Unexplored Dimension of Infection Dynamics

Mustard aphid, Lipaphis erysimi pseudobrassicae is an insect pest that feeds on phloem sap, causing significant damage to crops through direct feeding and virus transmission. This pest species harbors both primary and secondary endosymbionts that play crucial roles in their survival and interaction with the host plant. Among these endosymbionts, Buchnera aphidicola is the primary symbiont that compensates for nutrient deficiencies in the phloem sap diet, while several secondary endosymbionts, like Wolbachia sp, Arsenophonus sp, Rickettsia sp, Hamiltonella sp, Serratia sp and Cardinium sp serve various functional roles in the aphids. To understand the association between these primary and secondary endosymbionts in L. e. pseudobrassicae, we conducted species confirmation studies in 16 populations collected from 13 different states and 1 Union territory in India and used species-specific primers targeting 16S rRNA gene to detect the presence of these endosymbionts. The PCR amplification confirmed the occurrence of Buchnera sp in all individual aphids with 100% occurrence, followed by Wolbachia sp, Rickettsia sp, and Hamiltonella sp with 81.25% incidence and Cardinium sp least (31.25%). Overall, the current study revealed the presence of bacterial endosymbionts in L. e. pseudobrassicae populations from India, indicating the need for further research to better understand the implications of these endosymbionts on the biology of aphids and their potential impacts on crop health and management.