TOXICITY OF SOME INSECT GROWTH REGULATORS (IGRs) AND THEIR BINARY MIXTURES WITH OILS ON COTTON LEAFWORM LARVAE SPODOPTERA LITTORALIS (BOISD)

S. Hamed
2012 Journal of Plant Protection and Pathology  
Toxicity effects of tow insect growth regulators (IGRs) chlorfluazuron and flufenoxuron alone and their combinations with oils at quarter, half and recommended rates were studied by using second (2 nd ) and fourth 4 th larval instars of the cotton leafworm, Spodoptera littoralis. (Boisduval). The results achieved in this study can be summarized in the following, chlorfluazuron was more toxic on both 2 nd and 4 th larval instars than flufenoxuron when used alone at quarter, half and recommended
more » ... lf and recommended rates. Concerning the effect of binary mixtures of the tested compounds at half-and quarter recommended dose, chlorfluazuron when mixed with Kz oil exhibited highly mortalities against 2 nd i nstar larvae of field strain of S. littoralis which caused 96.17% as residual effect compared with chlorfluazuron when used alone (91.45%) at half recommended dose. While, chlorfluazuron + Hopa oil was recorded high mortality 94.47% at quarter-recommended dose as residual effect compared with chlorfluazuron when used alone (81.23%) at the quarter recommended rate .Also, Flufenuxuron + Hopa oil has the highest residual activity (95,25%) when compared to 79.10% for flufenuxuron alone at the half recommended rate. While, flufenuxuron + Misrona oil was recorded high mortality 82.93% as residual effect compared with 73.01% for flufenuxuron when used alone at the quarter recommended rate . Also, regarding the chlorfluazuron when mixed with Kz oil exhibited highly mortalities against 4 th instar larvae of field strain of S. littoralis which caused 95.40% as residual effect compared with chlorfluazuron when used alone (92.94%) at the half recommended rate. While, chlorfluazuron + Kz oil was recorded high mortality 92.62% as residual effect as compared with chlorfluazuron when used alone (80.48%) at the quarter recommended rate .The data also confirmed that, flufenuxuron + Hopa oil has the highest residual activity (93, 5%) when compared of 71.53% for flufenuxuron alone at the quarter recommended rate . While, flufenuxuron + Misrona oil was recorded high mortality 79.29% as residual effect compared with 70.96% for flufenuxuron when used alone at the quarter recommended rate . It could be concluded that,the oils when mixed with IGRS enhanced the toxicity effect of IGRs against 2 nd and 4 th instar larvae of field strain of S littoralis.
doi:10.21608/jppp.2012.83788 fatcat:z2vc2nvlazgrlppwyjlhoqes2a