Journal of Environmental Biology

Evaluating the virulence and endophytic colonization of Metarhizium anisopliae and Beauveria bassiana in Dalbergia sissoo seedlings for the biological control of subterranean termites

T.K. Bhoi¹*, D.K. Mahanta², I. Samal³, M.N. Raj⁴ and J. Komal⁵     

¹Forest Protection Division, ICFRE -Arid Forest Research Institute, Jodhpur-342 005, India

²Forest Entomology Discipline, Forest Protection Division, ICFRE-FRI, Dehradun- 248 006, India

³ICAR-National Research Centre on Litchi, Mushahari, Ramna, Muzaffarpur- 842 002, India

⁴Krishi Vigyan Kendra, Khunti-835 227, India

⁵Basic Seed Multiplication and Training Centre, Central Silk Board, Kharsawan-833 216, India

Received: 22 August 2024                   Revised: 19 December 2024                   Accepted: 14 February 2025

*Corresponding Author Email : bhoitanmaya152@gmail.com                     *ORCiD: https://orcid.org/0000-0003-2229-7792                     

Abstract

Aim: To evaluate the virulence and endophytic colonization efficacy of Metarhizium anisopliae and Beauveria bassiana in Dalbergia sissoo seedlings against Odontotermes obesus.

Methodology: Termites (O. obesus) were collected from infested wood and acclimatized at 26 ± 2^°C and 75 ± 5% RH. Active, uninjured workers were used for bioassays. M. anisopliae and B. bassiana cultures from ICAR-NBAIR were grown on SDA and PDA media, respectively, at 25 ± 1^°C. Conidia (1 × 108 conidia ml^-1) were suspended in sterile water with 0.05% Triton X-100. Termites were treated using a Potter spray tower, with controls receiving sterile water. Mortality was observed over seven days, and LT₅₀ values were calculated. D. sissoo seedlings were inoculated with fungal suspensions via soil drench and foliar spray. Colonization was assessed by re-isolating fungi from surface-sterilized plant tissues.

Results: M. anisopliae showed greater virulence against O. obesus, with a lower LT50 (32.84 hr) compared to B. bassiana (42.48 hr) and a steeper dose-response slope (4.88). Colonization studies revealed the M. anisopliae achieved higher rates in foliage (84.31%), roots (76.36%), and leaves (80.94%) compared to B. bassiana (74.32%, 60.52%, 69.98%, respectively), with significant differences noted in root and leaf colonization (P < 0.001).

Interpretation: M. anisopliae demonstrated superior termite control and higher colonization efficiency in D. sissoo seedlings, making it a promising agent for integrated pest management in forest ecosystems.

Key words: Beauveria bassiana, Dalbergia sissoo, Endophytic colonization, Metarhizium anisopliae, Termite

Copyright © 2025 Triveni Enterprises. All rights reserved. No part of the Journal can be reproduced in any form without prior permission. Responsibility regarding the authenticity of the data, and the acceptability of the conclusions enforced or derived, rest completely with the author(s).