Aim: The present study was undertaken to provide valuable insights regarding population genetic structure of Leucinodes orbonalis from diverse agro-ecologies of India. Methodology: Molecular characterization of L. orbonalis populations collected from five major agro-climatic zones of India was carried out using mitochondrial cytochrome oxidase I (COI) gene. Collected specimens were subjected to DNA extractions, partial PCR amplification and sequencing of the target gene, and multiple sequence alignments. Results: The results showed very less diversity in the nucleotide positions of the COI sequences of 79 studied specimens, with a low number of segregating sites (30), nucleotide diversity (0.00438) and overall mean genetic distance (0.004 ± 0.001). The significant negative values of neutrality tests and unimodal mismatch distribution supported the demographic expansion theory in Indian L. orbonalis. Analysis of the molecular variance revealed that 93.13% of the genetic variation was within populations, and the variation among populations was only 6.87%. The pairwise genetic differentiation was also found to be low to moderate between most of the populations. Multiple haplotypes were recorded from all the populations, and both neighbour-joining tree as well as the haplotype network showed that clustering of the haplotypes was independent of the geographical location. Interpretation: Thus, it can be inferred that Indian populations of L. orbonalis have very low genetic variation levels concerning the COI gene. There is a possible occurrence of stable inherited gene flow among populations, thereby reducing genetic variation in India.

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Aim: The present study was undertaken to explore the genetic diversity among Helicoverpa armigera populations from varied geographic regions of India using mitochondrial cytochrome c oxidase I (COI) gene fragments. Methodology: The larval specimens of H. armigera collected from 20 locations were subjected to DNA extraction, PCR amplification of target gene, sequencing and then multiple sequence alignments. Results: Based on COI sequence data, high levels of genetic differentiation among some H. armigera populations were detected, but divergence existing was not high enough to delineate them as separate species. The Indian population as a whole exhibited similarity with global genetic assemblage. Significant negative neutrality test indices and unimodal mismatch distribution further supported that this insect experienced a demographic expansion in the past. The phylogenetic tree and median-joining haplotype network indicated that genetic similarity was not related with geographic proximity of populations. Interpretation: Differences based on genetic analyses indicate considerable subspecific level variations among H. armigera populations of India. However, there is no existence of any unidentified cryptic species of H. armigera in the country.

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