Biology subjects

Ilias, A.

Publications and source records attributed to Ilias, A..

3 recordsLinked to original sources

bioRxiv2025

Evolving resistance patterns in Tetranychus urticae and Bemisia tabaci in Greece

Pesticide resistance in agricultural pests poses a significant challenge to sustainable crop protection. In this study, we assessed the current resistance status of two key pests, Tetranychus urticae and Bemisia tabaci, in major agricultural regions of Greece. A total of 25 field populations were collected between 2023 and 2025 and tested using single-dose toxicity bioassays and droplet digital PCR (ddPCR) for known resistance-associated target-site mutations. The results revealed significant variability in susceptibility to multiple acaricides and insecticides, with several T. urticae populations displaying reduced sensitivity to abamectin, hexythiazox, and fenpyroximate. Resistance mutations such as I321T (GluCl3), I1017F (CHS1), F1538I (VGSC), and G126S (cytb) were detected at high frequencies in multiple populations, indicating multi-resistant phenotypes. In B. tabaci, widespread occurrence of F331W (ace1), L925I/T929V (VGSC), and A2083V (acc) mutations confirmed evolving resistance to organophosphates, pyrethroids, and ketoenols, respectively. Our findings underscore the ongoing evolution of resistance in these pests and highlight the need for integrated management strategies that include regular resistance monitoring and judicious pesticide use. This study provides data to guide evidence-based pest control and supports the implementation of sustainable Integrated Pest Management (IPM) practices in Greece.

pharmacology and toxicology↗

bioRxiv2024

A Bioinert Hydrogel Framework for Precision 3D Cell Cultures: Advancing Automated High-Content and High-Throughput Drug Screening

Enhanced drug testing efficiency has driven the prominence of high-content (HC) and high-throughput (HT) screening (HCHTS) in drug discovery and development. However, traditional HCHTS in well-plates often lack complexity of in vivo conditions. 3D cell cultures, like cellular spheroids/organoids, offer a promising alternative by replicating in vivo conditions and improving the reliability of drug responses. Integrating spheroids/organoids into HCHTS requires strategies to ensure uniform formation, systemic function, and compatibility with analysis techniques. This study introduces an easy-to-fabricate, low-cost, safe, and scalable approach to create a bioinert hydrogel-based inverted colloidal crystal (BhiCC) framework for uniform and high-yield spheroid cultivation. Highly uniform alginate microgels were fabricated and assembled into a colloidal crystal template with controllable contact area, creating engineered void spaces and interconnecting channels within agarose-based BhiCC through the template degradation by alginate lyase and buffer. This results in a multi-layered iCC domain, enabling the generation of in-vitro 3D culture models with over 1,000 spheroids per well in a 96-well plate. The unique hexagonal-close-packed (HCP) geometry of iCC structure enables HCHTS through conventional plate reader analysis and fluorescent microscopy assisted by house-developed automated data processing algorithm. This advancement offers promising applications in tissue engineering, disease modeling, and drug development in biomedical research.

bioengineering↗

bioRxiv2023

Whitefly effector G4 interacts with tomato proteins of which MIPDB141 affects whitefly performance

The phloem-feeding insect Bemisia tabaci is an important pest, responsible for the transmission of several crop-threatening virus species. While feeding, the insect secretes a cocktail of effectors to modulate defense responses. Here, we present a set of proteins that was identified in artificial diet on which B. tabaci was salivating. We studied whether these candidate effectors can play a role in plant immune suppression. Effector G4 was the most robust suppressor of the flg22-induced ROS response when transiently expressed in Nicotiana benthamiana. In addition, G4 was able to supress ROS in Solanum lycopersicum (tomato) and Capsicum annuum (pepper). Fused to a fluorescence tag, G4 localized in the cytoplasm in N. benthamiana. A yeast two-hybrid screen combined with a luciferase bimolecular complementation and co-localization assays resulted in the identification of two target proteins in tomato: REF-like stress related protein 1 (RSP1) and meloidogyne-induced giant cell protein DB141 (MIPDB141). Silencing of MIPDB141 in tomato, using virus-induced gene silencing, reduced whitefly fecundity up to 40% demonstrating that the protein is involved in susceptibility to B. tabaci. Together our data demonstrate that effector G4 impairs tomato immunity to whiteflies by interfering with the ROS production and via a direct interaction with tomato susceptibility protein MIPDB141.

plant biology↗