Quaternary agrochemical composition suitable for controlling insects and fungi, comprising two insecticides selected from fipronil and thiamethoxam in combination with two fungicides selected from azoxystrobin and thiophanate-methyl. The present invention also relates to the agrochemical formulation comprising the above-mentioned composition of insecticides and fungicides mixed with acceptable agrochemical co-formulants for direct use on propagation material, particularly for use on seeds of useful plants. More particularly, the present invention relates to a composition containing fipronil, thiamethoxam, azoxystrobin and thiophanate-methyl in an optimal agronomic concentration ratio. Even more particularly, the present invention relates to an aqueous composition for treating seeds in ready-mix form comprising fipronil, thiamethoxam, azoxystrobin and thiophanate-methyl, in an optimal specific agronomic concentration ratio, in combination with agrochemically acceptable co-formulants. The present invention also relates to the preparation of said composition and to use thereof for controlling insects and fungi, particularly for protecting plant propagation material, such as seeds.L'invention concerne une composition quaternaire de défensifs agricoles appropriée pour lutter contre les insectes et les champignons, comprenant deux insecticides choisis parmi le fipronil et le tiaméthoxame en association avec deux fongicides choisis parmi l'azoxistrobine et le thiofanate-méthyle. La présente invention concerne également la formulation de défensifs agricoles, comprenant la composition susmentionnée d'insecticides et de fongicides en mélange avec des co-formulants agrochimiques acceptables, pour application directe sur des matériels de propagation, notamment pour application sur des graines de plantes utiles. Plus particulièrement, la présente invention concerne la composition de fipronil, de thiamétoxame, d'azoxistrobine et de thiofanate-méthyle en un rapport agronomique de
