Comparison between Toxicoiogicai and Biological Efficiency of some Aromatic Oils and other Compoundes on Two Spotted Spider Mite

Abstract

Control of the two spotted spider mite, Tetranychus urticae(Koch) using the conventional acaricides resulted in many problems . So, this study was carried out to evaluate the toxicity of certain alternative pesticides against this pest ,T. urticae as well as some biological aspects under laboratory conditions using two aromatic oils (Basil and Carnation) .one natural oil (Nat-1) and one conventional acaricide (Helbstar). The results indicated that Helbstar was the highest toxic compound to adult females of T. urticae followed by Nat-1 with Lc50 values of 1686.5 and 2861.5 ppm, respectively while Basil was the least toxic one with Lc50 value of 5990.4 ppm . The population showed more homogeneity in its response to the aromatic oils (Basil and carnation). Also, the results showed that the Helbstar caused the highest reduction in egg deposition with a mean number of 1.0 egg / day followed by Nat-1 with a mean number of 4.45 eggs / day , while Carnation was the lowest one with a mean number of 11.85 egg / day. The egg hatchability decreased with the increase of egg age at treatment by Basil , while in treating 1,2 and 3 day old eggs , the highest reduction in hatchability was found for Nat-1 , Helbstar and Carnation, with 100% reduction in hatchability at the three ages .Thus, the obtained results are of a great importance as they are taken into account in planning programs of integrated pest management.

Bio-efficiency of some Aromatic Oils and Other Compounds on Some Biological Aspects of Tetranychus urticae as Alternative to Pesticides.

“…and also Alkanz 2000 oil affected on mortality percentage of total immature of T. cucurbitacearum with a percentage about (73.33%)but Natcom (20/5) did not affect percentage of quiescent deuto-nymph of T. cucurbitacearum. , Miresmailli and Isman (2006) , Topuz and eler (2007), those mentioned that essential oils were used in the experiment had toxic effect to oviposition stage and adult females and caused a significant reduction to adult longevity of spider mite when spray method was used , Roh et al (2011 andMead ,2012) who mentioned that sandalwood oil ( essential oil ) caused mortality to adult females of T. urticae with percentage(87.2±2.9%) and also the previous results in agreement to Elsadany et al (2020) who mentioned that Helbstar was higher in reduction percentage of egg T. urticae than other tested compounds. Also some of result in partial agreement with Elsadany (2020) who stated that (Lc 50 ) conc.…”

“…While Basil oil had no effect on eggs hatchability with compared to control . These results in contrast to (EL-Duweini and Sedrak (1997), Gamieh et al (2000), Amer et al(2001), Magouz and Saadoon (2005), (Sertkaya et al (2010), Ismail and Abo Ghalia, 2011, Mead, 2012and Elsadany ,2020 where those mentioned that mineral oils as jojoba oil, Super Masrona oil, Natcom oil (20/5) and (Nat-1) oil causes high reduction to T. cucurbitacearum and T . urticae eggs .…”