Effect of Some Common Surfactants on the Emulsion Characteristics and Biological Performance of Insecticide Emulsifiable Concentrates

Accelerated storage of some of the common surfactants, solvents and cypermethrin and temephos toxicants before incorporation in emulsifiable concentrates revealed that the deterioration of emulsion stability due to surfactants was, at best, only as much as any other component of these concentrates. Heat sensitive surfactants such as polyoxyethylenated nonyl phenol seemed to be responsible for the effect. The test surfactants exhibited both synergistic as well as antagonistic effects with the insecticides, the effect being more pronounced at the higher 1:5, insecticide: surfactant, level. These did not reveal any visible phytotoxicity against Triticum aestivum var. WH 291, Lagenaria siceraria (MOD Standi, var: PSP Long and Solatium melongena L., var: Pusa aranti but the germination nnd seedling growth of Eleusine coracaca L. Gaertn were adversely affected. Various strains of Rhizobium sp. were inhibited at even low concentrations of surfactants. It was concluded that the diverse type of activity and fate of each surfactant to be used in pesticide formulation need to be thoroughly investigated.