Date of Publication
8-2025
Document Type
Bachelor's Thesis
Degree Name
Bachelor of Science in Biology major in Medical Biology
Subject Categories
Microbiology
College
College of Science
Department/Unit
Biology
Thesis Advisor
Ma. Luisa D. Enriquez
Defense Panel Chair
Divina M. Amalin
Defense Panel Member
Ma. Christine G. Ortiguero
Kris Lord T. Santos
Abstract (English)
Nephotettix virescens, also known as green leafhopper (GLH), is a common rice pest and a primary vector of Rice Tungro Virus (RTV) in Asia. Rice Tungro Disease (RTD) is known to cause dwarfing or stunting of rice plants and reduced tillering. Considering the severe impact of this disease, it is important to understand the biology of its insect vector, specifically its gut microbiota which influences key physiological functions, including insecticide resistance. However, rising resistance due to excessive insecticide use poses a serious threat to rice production. This study aimed to describe and compare the gut microbiota composition of field-collected (FC) and laboratory-reared (LR) adult GLH, and to identify bacterial genera potentially associated with insecticide resistance. DNA was extracted from a single insect per group and analyzed using 16S rRNA metabarcoding sequencing. The LR group had 47,264 raw reads and 4 ASVs while the FC group yielded 87,164 raw reads with 151 ASVs. Results show that LR samples contained the genera Berkiella, Sulcia, and Limosilactobacillus, in descending order of read abundance. FC samples displayed greater bacterial diversity. Dominant phyla included Proteobacteria, Bacteroidota, Actinobacteriota, Cyanobacteria, and Firmicutes. Sulcia had the highest read abundance in both groups, accounting for 66.3% in FC and 0.05% in LR. It was the only genus that was shared between the two groups. Other abundant genera in FC included Cutibacterium, Bacteroides, Acinetobacter, Staphylococcus, and Pseudomonas. The reduced microbial diversity in LR samples reflects the absence of environmental microbial exposure in controlled settings. Several bacterial genera identified in the FC group (i.e. Acinetobacter, Pseudomonas, and Bacteroides) have been previously linked to insecticide resistance, though further studies are needed to validate their roles in GLH. Approximately 14.6% of identified genera remained unclassified. These findings have implications for pest management strategies, particularly in identifying microbial biomarkers for resistance monitoring. It is recommended to increase sample size, include different life stages, and focus on midgut analysis in future studies. Culturing bacteria with insecticides could help determine specific resistance mechanisms.
Abstract Format
html
Abstract (Filipino)
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Abstract Format
html
Language
English
Format
Electronic
Keywords
Rice—Diseases and pests; Rice tungro spherical virus
Recommended Citation
Dalit, A. A., Oblepias, P. P., Padual, C. G., & Sarzate, M. G. (2025). Potential role of gut microbiota diversity in insecticide resistance of field-collected and laboratory-reared nephotettix virescens distant (Hemiptera: Cicadellidae). Retrieved from https://animorepository.dlsu.edu.ph/etdb_bio/158
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Embargo Period
8-8-2026
