Studies on new invasive pest Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and its natural enemies

Peste des petits ruminants (PPR) presents economic challenges in enzootic countries impacting small ruminant productivity. The state of Karnataka, India, implemented a mass vaccination campaign in alignment with the PPR-Global Eradication Programme (GEP) and the National Strategic Plan for PPR eradication. This study was conducted from January to March 2023 to assess seroconversion in post-vaccinated goats and sheep at the epidemiological unit (epi-unit) level, aligning with the World Organisation for Animal Health (WOAH) and the Food and Agriculture Organization (FAO) guidelines in the PPR Global Control and Eradication Strategy (GCES). Before vaccination, 3466 random serum samples were collected from small ruminants of three age groups (6–12 months, 1–2 years, and >2 years) across 116 epi-units, spanning 82 taluks in 28 districts. Post-vaccination sero-monitoring included 1102 serum samples collected from small ruminants of the 6–12-month age group only, across 111 epi-units covering 64 taluks in 23 districts. The PPRV antibody status was determined using an indigenous hemagglutinin (H) protein monoclonal antibody-based competitive ELISA kit. Pre-vaccination, the PPR seropositivity rates were 55%, 62%, and 66% in the age groups of 6–12 months, 1–2 years, and >2 years, respectively, with a 61% PPRV antibody prevalence across all the age groups. Notably, 41% of the epi-units exhibited antibody prevalence rates of ≥70%, indicating a substantial population immunity, possibly attributed to the previous vaccination program in the state since 2011. In contrast, only 17% of the epi-units had below 30% seroprevalence rates, emphasizing the need for intensified vaccination. Statistical analysis of the data revealed significant correlations (p < 0.05) between the presence of PPRV antibodies and host factors such as species, breed, and sex. Post-vaccination seroprevalence in the 6–12 months age group was found to be 73.4%, indicating the use of an efficacious vaccine. On the evaluation of vaccination immunity in the 6–12 months age group, it was revealed that over 69% of the epi-units achieved a response surpassing ≥70%, indicating a significant improvement from 42% of the epi-units in pre-vaccination. For active PPR eradication, a mass vaccination campaign (>95% coverage) targeting small ruminant populations aged >4 months is advocated, aiming to achieve the desired herd immunity of >80%. This study offers crucial insights into PPR baseline seroprevalence/immunity status and vaccine efficacy, guiding national strategies towards a PPR-free India and further supporting the global eradication initiative.

Baculoviruses are arthropod-specific pathogens, and find extensive applications in pest control strategies and recombinant protein expression. Spodoptera litura nucleopolyhedrovirus (SpltNPV) infects the tropical armyworm Spodoptera litura, which is an important polyphagous crop pest widely distributed in regions of Asia and Oceania. Using next-generation sequencing, we report stage-specific profiling of SpltNPV-encoded microRNAs (miRNAs) at different time intervals post-infection (p.i.) of Sf21 cells. Sequence length distribution analysis of the small RNA libraries revealed a significant increase in 20 nt reads and a reduction of other size fractions during late phases of infection. In silico miRNA prediction tools identified 48 novel SpltNPV-encoded miRNAs, of which 10 were validated experimentally in Sf21 cells using Northern blot analysis and TaqMan quantitative real-time (qRT)-PCR. The viral miRNAs were also found to be expressed in fat-body and mid-gut tissues of infected fifth-instar S. litura larva. qRT-PCR analysis confirmed that expression of most viral miRNAs was triggered 12 h p.i. and continued thereafter. Gene Ontology and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway annotation of computationally predicted targets of the reported miRNAs suggested a major impact of these miRNAs on cell signalling, protein translation and metabolic processes.

Paratelenomus anuRajmohana, Sachin & Talamas,sp. nov.(Hymenoptera: Scelionidae) is an egg parasitoid of the kudzu bug,Megacopta cribraria(Fab.) (Hemiptera: Plataspidae). It is morphologically and genetically distinct fromP. saccharalis(Dodd), a well-known egg parasitoid of the same host.Paratelenomus anuis here described from India and diagnosed from other species ofParatelenomusDodd. This parasitoid can be reared easily, has high rates of parasitism, and thus may be significant for the biological control ofM. cribraria.Phoresy is documented inP. anuand provides the first known example of this behavior inParatelenomus.Paratelenomus longus(Kozlov & Lê)syn. nov.andP. mangrovusRajmohana & Narendran,syn. nov.are treated as junior synonyms ofP. tetartus(Crawford), andP. obtusus(Lê)syn. nov.is treated as a junior synonym ofP. saccharalis.