51. Residual efficacy of deltamethrin against Sitophilus oryzae (L.), Rhyzopertha dominica (F.), Tribolium castaneum (Herbst) and Sitotroga cerealella (Oliv.) in wheat grain
- Author
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Pražić-Golić, Marijana, Pražić-Golić, Marijana, Kljajić, Petar, Andrić, Goran, Tamaš, Nenad, Pražić, Stefan, Pražić-Golić, Marijana, Pražić-Golić, Marijana, Kljajić, Petar, Andrić, Goran, Tamaš, Nenad, and Pražić, Stefan
- Abstract
Residual efficacy of the insecticide deltamethrin, an EC formulation containing 25 g/L AI + 225 g/L PBO (piperonyl butoxide synergist), against lab populations of Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum and Sitotroga cerealella was investigated in the laboratory by applying product water solutions (0.25 mg AI/kg) to wheat grain (at 25±1°C and 60±5% r.h.). Adult mortality on 0, 7, 14 and 30 days old deposits was estimated after 2, 7 and 14 days of exposure to treated wheat grain and additional 7 days of recovery. Progeny reduction (PR, %) was also assessed. After 2 days of exposure to deposits of all ages, deltamethrin caused only 0-10% mortality of coleopterans (up to 37% after the recovery period) and 23-30% of S. cerealella, while mortality before and after recovery from 14 days of exposure was 95-50% for S. oryzae, 97-100% for R. dominica, 99-100% for T. castaneum and 100% for S. cerealella. Progeny production of S. oryzae was highest after parents contacted with 14 days old deposit of deltamethrin (PR, 76%), and lowest after contact with fresh deposit (PR, 95%), while R. dominica and T. castaneum had no progeny on any deltamethrin deposit age in wheat (PR, 100%), and S. cerealella had only a very low progeny (PR, 99%). The results showed that the synergised deltamethrin, applied at 0.25 mg/kg in wheat grain, is a highly effective insecticide for stored-product insect control, while a higher dose is required for successful residual control of S. oryzae., Ispitivana je rezidualna efikasnost deltametrina, EC formulacije sa 25 g/L a.s. + 225 g/L PBO (piperonil butoksid) u suzbijanju laboratorijskih populacija Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum i Sitotroga cerealella nanošenjem vodenog rastvora insekticida (0.25 mg a.s./kg) na pšenicu u zrnu u laboratorijskim uslovima (25±1°C i 60±5 % r.v.v). Smrtnost adulta na depozitima starosti 0, 7, 14 i 30 dana je utvrđivana posle 2, 7 i 14 dana izlaganja u tretiranoj pšenici i 7 dana oporavka adulta (izuzev S. cerealella) u netretiraoj pšenici. Takođe je utvrđivana i produkcija potomstva izlaganih roditelja (PR, %). Posle 2 dana izlaganja bez obzira na starost depozita, deltametrin je prouzrokovao 0-10% smrtnosti tvrdokrilaca (posle oporavka do 37%) i 23-30% smrtnosti S. cerealella, dok je posle 14 dana izlaganja smrtnost S. oryzae pre i posle perioda oporavka bila 95-50%, R. dominica 97-100%, T. castaneum 99-100% i S. cerealella 100%. Najveći broj potomaka S. oryzae je utvrđen posle kontakta roditelja sa 14 dana starim depozitom deltametrina (PR, 76%), a najmanji posle kontakta sa svežim depozitom (PR, 95%), dok u tretiranoj pšenici, bez obzira na starost depozita, nije bilo potomaka R. dominica i T. castaneum (PR, 100%), dok je kod S. cerealella zabeležen mali broj potomaka (PR, 99%). Na osnovu dobijenih rezultata može se zaključiti da je sinergizovani deltametrin primenjen u količini 0,25 mg/kg pšenice visoko efektivan u suzbijanju skladišnih insekata, dok je za dužu zaštitu pšenice od S. oryzae potrebno primeniti veću dozu ovog insekticida.
- Published
- 2018