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Three entomopathogenic nematode populations were isolated from agricultural fields in the Anantnag district of Jammu and Kashmir (India). Sequences of multiple gene regions and phenotypic features show that they are conspecific and represent a novel species. Molecular and morphological features provided evidence for placing the new species into the “Kushidai” clade. Within this clade, analysis of sequence data of the internal transcribed spacer (ITS) gene, the D2D3 region of the 28S rRNA gene, the mitochondrial cytochrome oxidase I (mtCOI) gene, and the mitochondrial 12S (mt12S) gene depicted the novel species as a distinctive entity closely related to Steinernema akhursti, S. kushidai, and S. populi. Phylogenetic analyses also show that the new species is a sister species to S. akhursti, and these two species are closely related to S. kushidai and S. populi. Additionally, the new species does not mate or produce fertile progeny with any of the closely related species, reinforcing its uniqueness from a biological species concept standpoint. The new species is further characterized by the third-stage infective juveniles with almost straight bodies (0.7–0.8 mm length), poorly developed stoma and pharynx, and conoid-elongate tail (49–66 µm) with hyaline posterior part. Adult females are characterized by short and conoid tails bearing a short mucron in the first generation and long conoid tails with thin mucron in the second generation. Adult males have ventrally curved spicules in both generations. Moreover, the first-generation male has rounded manubrium, fusiform gubernaculum, conoid and slightly ventrally curved tails with minute mucron, and the second generation has rhomboid manubrium anteriorly ventrad bent, and tails with long and robust mucron. The morphological, morphometrical, molecular, and phylogenetic analyses support the new species status of this nematode, which is hereby described as Steinernema anantnagense n. sp. The bacterial symbiont associated with S. anantnagense n. sp. represents a novel species, closely related to Xenorhabdus japonica. These findings shed light on the diversity of entomopathogenic nematodes and their symbiotic bacteria, providing valuable information for future studies in this field.

Mosquitoes are important vectors, which transmit many communicable diseases throughout the world. Synthetic insecticides, such as organophosphate and pyrethroids, are commonly used for their control in the vector control program. Insecticidal compounds from natural sources, notably from plants and synthesized nanoparticles (NPs) are promising tools for managing such vectors. Hence, the study aimed to analyze the insecticidal potentiality of leaf extract of Cipadessa baccifera and synthesized ZnNPs against three major mosquito vectors. The results recorded from UV-Vis spectroscopy show the peak absorption spectrum at 420 nm. In FTIR, the maximum peak value is 562.85 cm−1 assigned to the N–H group (amide group). The EDAX analysis shows a peak around 63.29, which confirms the binding intensity of selenium. In the scanning electron microscopy analysis, the synthesized ZnNPs sizes were ranging from 49.21 to 65.43 nm. The synthesized ZnNPs produced high mortality against Culex quinquefasciatus LC50 = 0.049653 mg·mL−1; LC90 = 0.9842 mg·mL−1), Anopheles stephensi (LC50 = 0.053421 mg·mL−1 and LC90 = 0.027761 mg·mL−1), and Aedes aegypti LC50 = 0.55214 mg·mL−1 and LC90 = 0.7456 mg·mL−1). These results suggest that the C. baccifera leaf extract-mediated biosynthesis of ZnNPs has the potential to be used as an ideal eco-friendly approach toward the control of mosquito vectors at early stages.

Ectothermic organisms including insects are highly vulnerable to climate warming which not only influences their biology, ecology and physiology but also affects their symbiotic gut microbiota. This study determined the impact of ambient (control) and simulated warmer (heating) climatic conditions on the microclimate of brood nest and gut bacterial abundance of two Apis mellifera subspecies i.e. A. mellifera ligustica and A. mellifera sinisxinyuan. For both subspecies, brood nest temperature and relative humidity under the heating treatment were significantly different (p≤0.001) than those under the control treatment. Quantitative PCR data revealed that the abundance of gut bacteria (16S rRNA gene copy numbers) of A. mellifera ligustica and A. mellifera sinisxinyuan larvae was significantly higher (P≤0.05), 1.73 and 5.32 fold higher respectively, during the heating treatment than those in control conditions. Although gut bacterial abundance of A. mellifera ligustica (1.67 × 107 copies g−1 fw) and A. mellifera sinisxinyuan (1.7 × 107 copies g−1 fw) larvae was similar during the control treatment, A. mellifera sinisxinyuan larvae exhibited three times greater gut bacterial abundance than A. mellifera ligustica during the heating treatment. Similarly, adult A. mellifera sinisxinyuan bees harboured significantly greater bacterial abundance during the heating treatment than control. These findings elucidate that climate warming may significantly affect the honeybee colony microclimate and their gut bacterial abundance. However, further studies are needed to better understand how gut microbial community may influence the learning, physiological and behavioural mechanisms of the host bees in a climate warming scenario.

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a destructive pest of Zea mays (maize) and other agricultural crops. The synthetic insecticides predominantly used against this pest lead to pest resistance, environmental contamination and health hazards. This study evaluated nanoformulated aqueous extracts of some promising local plant species against third instar larvae of S. frugiperda under laboratory and field conditions. The initial screening bioassay showed highest larval mortality with a 20% extract of Nicotiana tabacum L. (66.67%), followed by Azadirachta indica A. Juss. (53.33%), Withania somnifera L. (46.67%), Melia azedarach L. (40%) and Dodonaea viscosa Jacq. (33.33%). The two most effective plant extracts (A. indica and N. tabacum) were further nanoformulated with silver nitrate (AgNO3) and bioassayed against S. frugiperda larvae using different concentrations. The results showed that these nanoformulated extracts caused significant larval mortality, with LC50 (lethal concentration that kills 50% of the population) and LT50 (lethal time to kill 50% of the population) values of 37.36 and 28.21% at 72 h, and 52.19 and 33.25 h at 80% concentration, respectively. Field experiments on Zea mays L. (maize) plants showed maximum larval reduction by nanoformulated A. indica extract (48%), followed by N. tabacum extract (36%), whereas 80% and 20% larval reduction was noted for the positive (SuperLock®, emamectin benzoate and tebufenozide) and the negative (water) controls, respectively. Furthermore, characterization of both silver nanoparticles‐based plant extract formulations was performed using ultraviolet–visible (UV–vis) spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM) techniques, which confirmed the formation of silver nanoparticles. It is concluded that nanoformulated plant extracts can be an effective alternative to synthetic pesticides in combatting S. frugiperda and other lepidopteran pests. [ABSTRACT FROM AUTHOR]

Lung cancer, particularly non-small cell lung cancer (NSCLC), is a leading cause of cancer-related deaths worldwide. This study investigates the molecular mechanisms behind the anti-cancer effects of the tropical desert plant Retama raetam (R. raetam) on the A549 NSCLC cell line. The research examined R. raetam's anti-proliferative effects, cytotoxicity, apoptosis, reactive oxygen species (ROS) generation, mitochondrial membrane potential, and cell morphology in NSCLC A549 and L-132 cells. In addition, the influence of R. raetam on DNA fragmentation, apoptotic signaling, and PI3K/Akt pathways for its anti-cancer mechanism was examined. Our results indicated that R. raetam's effects were dose- and time-dependent to exhibit anti-proliferative effects on A549 cells. R. raetam treatment promoted apoptotic cell death cycle arrest, increased apoptotic cells, depolarized the mitochondrial membrane, and induced morphological alterations in cells and nuclei. It also inhibited A549 cell migration (P < 0.05), colonization, and invasiveness. Moreover, the study demonstrated that R. raetam treatment resulted in the upregulation of Bax expression, downregulation of Bcl-2 expression, and apoptotic fragmented DNA in A549 cells. The top five bioactive compounds derived from R. raetam exhibited molecular interactions that inhibit PIK3CA and AKT1. This inhibition leads to an increased frequency of apoptosis and subsequent death of cancer cells. Additionally, R. raetam extract induced an increase in ROS formation and cytochrome c levels, indicating that its toxic effects on A549 cells involve both ROS-dependent cytotoxicity through the disruption of mitochondrial transmembrane potential ΔΨm and ROS-independent cell cycle arrest through downregulation BCL-2, PARP, E-Cadherin, PI3K, and Akt expressions pathways. [ABSTRACT FROM AUTHOR]