Characterization of a new isolate of entomopathogenic nematode, Steinernema sangi (Rhabditida, Steinernematidae), and its symbiotic bacteria Xenorhabdus vietnamensis (γ-Proteobacteria) from Mizoram, northeastern India

Abstract

A survey was conducted to isolate indigenous EPN, specifically from the northeastern part of India, a biodiversity hotspot region, to record the occurrence and their further use as biological control agent. The morphological and molecular analysis (ITS rDNA for and 16S rRNA for) revealed that the entomopathogenic nematodes isolated from four different habitats and its symbiotic bacteria are conspecific with and respectively. The phylogenetic analysis based on maximum parsimony (MP) revealed that belongs to-- group. The study constitutes the first report of and its symbiotic bacteria outside the type locality, Vietnam, and in particular from India.

Morphological and molecular characterization of entomopathogenic nematode, Heterorhabditis baujardi (Rhabditida, Heterorhabditidae) from Mizoram, northeastern India

“…Gene amplification were performed using primers TW81 (5 0 -GTTTCCGTAGGTGAA CCTGC-3 0 ) forward and AB28 (5 0 -ATATGCTTAAGTT-CAGCGGGT-3 0 ) reverse for ITS (Joyce et al 1994); (5 0 -CGATAGCGAACAAGTACCGAGAG-3 0 ) forward and (5 0 -CCTGCTCAGGCATAGTTCACCATC-3 0 ) reverse for 28 S (Qiu et al 2011); and LCO 1490 (5 0 -GGTCAA-CAAATCATAAAGATATTGG-3 0 ) forward and HCO 2198 (5 0 -TAAACTTCAGGGTGACCAAAAAATCA-3 0 ) reverse for COI (M1-M6 partition) (Folmer et al 1994). The conditions for PCR amplification of ITS and 28S region was similar and follows Lalramnghaki et al (2017); and a condition for COI was: 94°C for 3 min (1 cycle), followed by 94°C for 1 min (36 cycles), 50°C for 30 s and 72°C for 45 s, followed by a final extension at 72°C for 7 min. Sequencing of the PCR products were done in both directions at Agrigenome, Kochi, Kerala, India.…”

“…In India, numerous surveys have been conducted to isolate the indigenous EPNs, resulting in the discovery of a new H. indica (Poinar et al 1992) from Coimbatore, Kerala. There are altogether eleven species of valid entomopathogenic nematodes documented from India (Ganguly and Singh 2000;Hussaini et al 2001;Ganguly et al 2002Ganguly et al , 2011Lalramliana and Yadav 2010;Kulkarni et al 2012;Bhat et al 2017;Lalramnghaki et al 2017), and the valid species includes Heterorhabditis bacteriophora, H. indica, S. abbasi (= S. thermophilum), S. bicornutum, S. carpocapsae (= S. meghalayense), S. glaseri, S. hermaphroditum (= S. dharanai), S. riobrave, S. sangi, S. siamkayai and S. surkhetense.…”

Evaluation of pathogenicity of indigenous entomopa-thogenic nematodes (Steinernematidae and Heteror-habditidae) from Mizoram, India, against tobacco cutworm, Spodoptera litura (Fabricius, 1775)

“…Indigenous isolates of EPN are considered more effective than exotic species for pest control in the local environment (Bedding, 1990). So far, two species of EPN, S. sangi and H. baujardi were reported from Mizoram (Lalramnghaki et al, 2017;Vanlalhlimpuia et al, 2018), and the present assessment of their efficacy against insect pest will contribute to enhancement of biological control method of the region in future.…”

Horizontal transfer of microbial toxin genes to gall midge genomes

“…The cecidomyiid RHS proteins form a single clade sister to Xenorhabdus vietnamensis , a symbiotic bacteria of the entomopathogenic nematode Steinernema sangi (Lalramnghaki et al 2017) ( Figure 3 ). This clade, in turn, is sister to a group that includes Xenorhabdus and Photorhabdus species, which are associated with nematode parasitism of insects (Boemare 2002; Busby et al 2013).…”