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Background and Objective Invasive thrips, Thrips parvispinus Karny recently reported in India, causing a widespread severe infestation in more than 0.4 million ha of chilli (Capsicum annum L.) growing areas. This species is native to Thailand and most prevalent in other South East Asian countries. Large scale cultivation of the major host plants (chilli and papaya), and favourable climatic conditions in India and other countries similar to native range of Thrips parvispinus expected to favour its further spread and establishment to new areas. Materials and Methods The present study was undertaken to confirm invasive thrips species identity through both morphological and molecular approaches and predict its potential invasion using the maximum entropy (MaxEnt) algorithm. Results The model predicted species range in respect of discrimination of suitable and unsuitable areas for its occurrence both in current and future climatic scenarios. The model provided a good fit for species distribution with a high value of area under the curve (0.957). The jackknife test indicated annual mean temperature and precipitation were found to be the most important bioclimatic variable in determining the distribution of T. parvispinus. High suitability areas were predicted in the countries wherever its occurrence was reported with high discrimination ability of suitable and unsuitable areas. Key distinguishing morphological characters of T. parvispinus were illustrated through high-resolution scanning electron microscopic images. Conclusion The identity of the thrips causing wide spread damage in chilli confirmed through morphological and molecular approaches. Key identifying characters were described through high resolution scanning electron microscopic images for accurate identification of the species. MaxEnt model identified high suitability regions for the potential establishment of T. parvispinus in India and other parts of the world. This study facilitates forecasting of further spread and also suggests imposing strict domestic quarantine measures to curtail its establishment in the new areas.

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is an invasive pest native to the American continent. The present study focused on bio-intensive tactics like intercropping, using natural enemies, botanical insecticides and biopesticides for managing S. frugiperda for the organic production of maize in Indian conditions. A total of eight different parasitoids attacking the different stages of S. frugiperda viz., eggs and larvae were found in the study area. The total parasitism rate due to all the parasitoids ranged from 28.37 to 42.44%. The egg-larval parasitoid, Chelonus formosanus Sonan (Hymenoptera: Braconidae) was the dominant parasitoid (12.55%), followed by Chelonus nr. blackburni (Hymenoptera: Braconidae) (10.98%) and Coccygydium sp. (4.85%). About 36.58 percent of the egg masses collected was parasitized by egg parasitoids, among which Telenomus remus (Nixon) (Hymenoptera: Scelionidae) was the dominant parasitoid. The botanicals insecticides such as citronella and annona extract were most effective, resulting in 100% mortality of FAW larvae (168 h after treatment). The essential oil of garlic (100%) was found highly effective in inhibiting egg hatching, followed by geraniol (90.76%). The maize intercropped with lady’s finger (okra) recorded significantly the lowest pest infestation and recorded higher grain yield (6.17 q/ha) than other intercropping systems and control (5.10 q/ha). The overall bioefficacy of commercial biopesticides against the larvae of S. frugiperda was in the following order azadirachtin > Metarhizium anisopliae (Metch.) Sorokin (Hypocreales: Clavicipitaceae) > Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) at 168 h after treatment.

Background: Phosphine resistance in Tribolium castaneum challenges grain storage. This study investigates the impact of cytochrome P450 (CYP) enzymes and CYP346 family genes on phosphine resistance in Indian Tribolium castaneum populations., Methods: Seven field populations of T. castaneum were compared with Lab- susceptible population for their resistance to phosphine. The levels of cytochrome P450 enzyme and expression of certain CYP346 family genes were tracked in these populations., Results: The highly resistant Patiala population showed significantly increased CYP450 activity (11.26 ± 0.14 nmol/min/mg protein, 7.41-fold higher) compared to the lab-susceptible population (1.52 ± 0.09 nmol/min/mg protein) when assayed using 8 mM p-nitroanisole as the substrate. The mRNA expression was measured relative to the standard gene RPS18 and revealed significant upregulation of CYP346B1 and CYP346B3 in highly resistant populations Moga and Patiala ( CYP346B1 : 12.09 ± 2.19 to 21.74 ± 3.82; CYP346B3 : 59.097 ± 10.265 to 50.148 ± 8.272). Patiala's CYP346B1 exhibited an impressive 685.76-fold change, and Moga's CYP346B3 showed a 361.893-fold change compared to lab-susceptible. Linear regression confirmed robust fits for each gene (R2: 0.693 to 0.756). Principal component analysis (PCA) demonstrated a strong positive correlation between CYP346 genes expression; and cytochrome P450 activity. Patiala, Moga, and Hapur populations showed conformity, associating higher resistance with increased P450 activity and CYP346 gene expression. Cluster analysis highlighted a potential correlation between CYP346B1 , CYP346B2 , and CYP346B3 and P450 activity, with Patiala and Moga clustering together., Conclusions: Variability in CYP346B1 and CYP346B3 in strong resistance populations may contribute to adaptation and resistance mechanisms. The study provides insights into specific CYP346 family genes associated with phosphine resistance, emphasizing the intricate interaction between CYP450 detoxifying enzymes, CYP346 family genes, and resistance mechanisms. The upregulation of CYP346 genes suggests a survival advantage for T. castaneum against phosphine, diminishing phosphine's efficacy as a pest control measure., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Published by IMR Press.)