Helalia, A.R. <br/><br/>
Effect of certain insecticides in enhancing the potency of bacillus thuringiensis against the cotton leafworm spodoptera littoralis  [electronic resource]. 
 تأثير بعض المبيدات الحشرية فى زيادة فعالية المركبات البكتيرية باسيلس ثورنجنسيس ضد دودة ورق القطن. 

 - p.573-580. 
<br/><br/>Includes reference. 
<br/><br/> The joint action of deltamethrin, chlorpyrifos-ethyl, methomyl and hexaflumuron with the biocides Xentari, Protecto and Dipel2x against the 2nd instar larvae of the cotton leafworm Spodoptera littoralis was studied. The results indicate that the toxicity of the tested biocides was greatly enhanced by the LC50 and LC25 of deltamethrin in admixture with each of them. The LC25 of deltamethrin increased the toxicity of all experimental biocides by co-toxicity factors ranging between 46.67 and 92.94. Results also indicate that all tested biocides were potentiated when used in admixture with chlorpyrifos-ethyl particulary when used at its LC25 concentration. On the contrary, methomyl when used at the two sublethal concentrations caused antagonistic or additive effects for Xentari, Protecto and Dipel 2x. Most combinations of tested biocides with hexaflumuron resulted in additive effect. However, when hexaflumuron was used at its LC25 in admixture with the (recommended rate) of the tested biocides a reasonable synergism level was produced. 
<br/><br/><br/>Summary in Arabic. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Cotton--Diseases and pests resistance.<br/>Cotton--Insecticides.<br/>Cotton leafworm.<br/>Bacillus thuringiensis.