Effects of Thyme and Rosemary essential oils on population growth parameters of Macrosiphum rosae (Hemiptera: Aphididae) on cut flower rose

The effect of thyme Thymus vulgaris L. androsemary Rosmarinus officinalis (L.) essential oils on life table parameters of red rose aphid Macrosiphum rosae (L.) oncut flower rose Rosa hybrida L. were investigated in laboratory conditions (27 ± 2 oC, 70 ± 5% humidity and a photoperiod of 16L:8Dh), during 2014-2015. The results on the basis of LC50 values showed that the M. rosae was significantly more sensitive to the oil of T. vulgaris (LC50 = 36621 ppm) than R. officinalis (LC50 = 57565 ppm). Also, Investigation of the thyme essential oil on life table parameters of M. rosae showed that the net reproductive rate (R0) values changed from 16.62 ± 2.31 to 29.10 ± 1.97 female offspring, the intrinsic rate of increase (r) values ranged from 0.177 ± 0.01 to 0.229 ± 0.13 day-1, the mean generation time (T) was 13.92 ± 0.22 to 15.88 ± 0.19 days, the DT values ranged from 3.01 ± 0.05 to 3.90 ± 0.007 days and the finite rate of increase (λ) values was 1.19 ± 0.003 to 1.26 ± 0.06 day-1. Also, the rosemary essential oil on life table parameters of red rose aphid revealed that the R0 values ranged from 17.87 ± 1.97 to 31.97 ± 1.98 female offspring,the r values ranged from 0.185 ± 0.02 to 0.237 ± 0.001 day-1, the mean generation time (T) was 14.45 ± 0.23 to 15.99 ± 0.21 days, the DT ranged from 2.85 ± 0.14 to 3.71 ± 0.14 days and the λ values was 1.20 ± 0.01 to 1.27 ± 0.02 day-1.The results revealed that the essential oils of rosemary and thyme used in this research had a significant difference on population parameters of rose aphid. The maximum mortality percent of M. rosae population registered 86.12 ± 1.02% and 90.21 ± 1.12% for rosemary and thyme essential oils, respectively. Hence, T. vulgaris had higher insecticidal effect than R. officinalis essential oil on rose aphid population.