The Efficacy of Some Plant Extracts, Pesticides and Natural Enemies in Controlling of Tetranychus urticae Koch Populations on the Greenhouse Tomato

Ibraheem Aziz Sakr(1), Mageda Muhammad Mufleh(2), Randa Ahmad Suliman*(1)

(1). Department of Plant Protection, Faculty of Agriculture, Tishreen University, Latakia, Syria.
(2). General Commission for Scientific Agricultural Research, Damascus, Syria.

(*Corresponding author: Eng. Randa Ahmad Suliman. E-Mail:

Received: 28/12/2017                                         Accepted: 10/04/2018


This study was conducted in order to evaluate the efficacy of the aqueous extracts of three plants (Melia azedarach L., Smilax asepra L. and Styrax officinalis L.), three pesticides (acetamiprid, abamectin and pyridaben) and releasing of two predators (Phytoseiuls persimilis Athias–Henriot and Stethorus gilvifrons Mulsant) in controlling of Tetranychus urticae Koch populations in tomato greenhouse. At 1st week of applications, S.officinalis and M.azedarach extracts showed a significant efficacy of 64.79 % and 56.45 %, respectively, as well as a decline in the efficacy of the S.aspera extract was noticed (35.26%). The killing percentage reached up to 68.95% under the treatment of acaricide, and pyridaben after 24 hours of the treatments and exceeded up to 80 % at the 1st week, simultaneously the abamactin showed high percentage (65.33 % and 78.43 % after 24 hours and 1st week, respectively), while the efficacy of the pesticide acetamiprid was very low and reached the highest record of 37.28 % at the 1st week. The efficacy of the predators P. persimilis and S. gilvifrons simultaneously increased and controlled T.urticae populations three weeks after treatment, and P. persimilis showed more efficiency (53.72 % and 58.12% for P. persimilis and 35.71 % , 47.11% for S. gilvifrons, in the 3rd and the 4th week, respectively). The M. azedarach extracts was superior to all plant extracts with a significant difference. The efficacy of the treatments of both the plant extracts and the chemical pesticides reduced significantly in the 2nd, 3rd and 4th weeks, as well as the natural-origin compound abamectin recorded high efficacy with no significant difference with the treatment of the specialized acaricide pyridaben, while there was a significant difference comparing with the other treatments.
Keywords: Plant extract, Chemical pesticides, Predator release, Tetranychus urticae, Stethorus gilvifrons, Phytoseiulus persimilis.

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