Tarbiat Modares University Journal of Crop Protection 2251-9041 14 1 2025 02 01 Compatibility and efficacy of Beauveria bassiana with selected insecticides and fungicides for managing Thrips tabaci (Thysanoptera: Thripidae) 101 115 27586 10.48311/jcp.2025.76162.0 EN Sana Lotfi Department of Plant Protection, Faculty of Agriculture, University of Zabol, Zabol, ‎Iran Ali Mirshekar Department of Plant Protection, Faculty of Agriculture, University of Zabol, Zabol, ‎Iran.‎ Abbas Khani ‎Department of Plant Protection, Faculty of Agriculture, University of Zabol, Zabol, Iran‎ Mahdi Pirnia ‎, Department of Plant Protection, Faculty of Agriculture, University of Zabol, Zabol, ‎Iran‎ Journal Article 2024 05 12 <span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">Onion thrips, <em>Thrips tabaci</em> Lindeman (Thysanoptera: Thripidae), is a major pest in Iran, causing significant agricultural losses. Biological control methods are crucial for reducing reliance on chemical insecticides and fungicides, minimizing environmental pollution, and mitigating insect resistance. This study evaluated the toxicity of the insecticides flonicamid and thiocyclam, the pathogenicity of <em>Beauveria bassiana</em>, the compatibility of the fungicides iprodione and carbendazim, and famoxadone and cymoxanil with <em>B. bassiana</em>, and the efficacy of insecticide-fungus combinations against second-instar onion thrips. A completely randomized design with four replications was conducted under laboratory conditions. Results showed that LC₅₀ values for thiocyclam, flonicamid, and <em>B. bassiana</em> were 4.3 mg L</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁻</span><span style="font-size: 10.0pt;">¹</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">, 2.3 mg L</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁻</span><span style="font-size: 10.0pt;">¹</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">, and 5.4 × 10</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁷</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;"> conidia mL</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁻</span><span style="font-size: 10.0pt;">¹</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">, respectively. Thrips mortality increased with higher concentrations and longer exposure to insecticides and <em>B. bassiana</em>. Flonicamid did not affect the germination or mycelial growth of<em> B. bassiana</em>, making it a compatible insecticide. However, iprodione + carbendazim and famoxadone + cymoxanil severely inhibited <em>the biological activity of B. bassiana</em>, making them unsuitable for integrated pest management (IPM). The combination of <em>B. bassiana</em> (6 × 10</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁷</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;"> conidia mL</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁻</span><span style="font-size: 10.0pt;">¹</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">) and flonicamid (1.2 mg L</span><span style="font-size: 10.0pt; font-family: 'Cambria Math',serif; mso-bidi-font-family: 'Cambria Math';">⁻</span><span style="font-size: 10.0pt;">¹</span><span style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi;">) was the most effective treatment against onion thrips. This combination could serve as an alternative to chemical insecticides in IPM programs, pending field validation.</span><br><span lang="FA" style="font-size: 10.0pt; mso-ascii-font-family: 'Times New Roman'; mso-ascii-theme-font: major-bidi; mso-hansi-font-family: 'Times New Roman'; mso-hansi-theme-font: major-bidi; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: major-bidi; color: black; mso-bidi-language: FA;">‎</span><br><br>  https://jcp.modares.ac.ir/article_27586_597626eebeefc042afb36a69a049696d.pdf