Tarbiat Modares University Journal of Crop Protection 2251-9041 3 4 2014 12 01 Efficacy of one botanical and three synthetic insecticides against silverleaf whitefly, Bemisia tabaci (Hem.: Aleyrodidae) on cucumber plants in the field 435 441 1152 10.48311/jcp.2014.1152 EN Gholamreza Golmohammadi Department of Agricultural Entomology Research, IranIan Research Institute of Plant Protection, Tehran, Iran. Ali Hosseini-Gharalari Department of Agricultural Entomology Research, Iranian Research Institute of Plant Protection, Tehran, Iran. Mohammadithaghi Fassihi Agricultural and resource natural research, Busher province. Roya Arbabtafti Department of Agricultural Entomology Research, Iranian Research Institute of Plant Protection, Tehran, Iran. Journal Article The silverleaf whitefly, <em>Bemisia tabaci</em> (Hem.: Aleyrodidae), is a key pest of greenhouse crops. Nymphs and adults feed on plant sap and excrete honeydew, resulting in reduction of yield and quality. This pest has a high potential for developing resistant biotypes against different insecticides. Therefore, it is necessary to study the efficacy of different categories of insecticides against <em>B. tabaci</em>. In this research, efficacy of imidacloprid (0.5 l/ha), thiacloprid + deltamethrin (0.75 l/ha), pyrethrum (4 l/ha) and<em>thiamethoxam </em>+ <em>lambda</em>-<em>cyhalothrin (</em>0.3 and 0.4 l/ha) with four replications were studied in a completely randomized block design in Yazd and Bushehr provinces of Iran. Mean (± SE) efficacy of imidacloprid, thiacloprid + deltamethrin, pyrethrum and<em>thiamethoxam </em>+ <em>lambda</em>-<em>cyhalothrin (</em>0.3 and 0.4 l/ha) were 73.42 ± 3.41, 89.57 ± 2.86, 90.29 ± 2.79, 68.13 ± 3.37 and 75.62 ± 3.76% against <em>B. tabaci</em> nymphs 7 days after treatment in Yazd, respectively; while in Bushehr, they were 57.30 ± 3.37, 68.45 ± 4.65, 64.17 ± 2.87, 30.0 ± 4.56 and 53.0 ± 3.35%, respectively. Thiacloprid + deltamethrin, pyrethrum and thiamethoxam + <em>lambda</em>-<em>cyhalothrin (at 0.4 l/ha)</em> can be suitable candidates in IPM programs of <em>B. tabaci</em>. Bemisia tabaci Insecticide efficacy Cucumber https://jcp.modares.ac.ir/article_1152_45f31d16b1058d586fc3be7207b58053.pdf