ارزیابی اثر حشره‌کش میکروبی Bacillus thuringiensis و اختلاط آن با پودر حنا بر شب‌پره شمشاد Walker (Lep.: Crambidae) Cydalima perspectalis

Abstract
The bux moth, Cydalima perspectalis Walker (Lep.: Crambidae), has been identified as the most important pest of the genus Buxus in the world. This pest was introduced into Iran in 2015 and became highly invasive and destructive on Buxus hyrcana in the Northern Forests of Iran. The aim of this study was the evaluation of Spanish Bacillus thuringiensis as a microbial pesticide to control of the bux moth and its combination with Henna as a synergist. Experiments were performed in a completely randomized design and were evaluated on second instar larvae of C. perspectalis under laboratory conditions (27±1̊C, 65±10 R.H. and 16:8 L: D). At first, the mortality rate of the three concentrations of the Btk (300, 500 and 1000 g/L) with control (water) was analyzed in six replications, then the effect of combination of tow concentrations of 300gr/1000LBtk + Henna powder (1 and 2gr) were investigated with three replications. The mortality of larvae after 48h for the mentioned concentrations of Btk were 33,63 and 100%, respectively. The results showed that if henna powder, which is an inexpensive and available adjuvant compound were added to the Btk in spray tank, it could increase the mortality rate from 33to 100% after 48h, and become more affordable to control C. perspectalis. This synergistic effect was similar when the dose of insecticide becomes triples.