21 January 2000

Formulation effects

TOP triazole fungicide epoxiconazole gives more kickback disease control in its original Opus formulation than an equivalent amount in a formulated mix with the strobilurin kresoxim-methyl (Landmark), claims a leading agronomist.

"Results from trials last year have confirmed our suspicion that the epoxiconazole in Landmark has nothing like the eradicant activity of the epoxiconazole in Opus," said Doug Stevens of Morley Research Centre.

His comments are based on trials comparing a mix of half rate Opus plus Bravo (chlorothalonil) with half or three-quarter rate Landmark. Assessment of leaf four showed half rate Opus plus Bravo matched the disease control of three-quarter rate Landmark. Only when the more recently emerged final leaf two was checked did the epoxiconazole and kresoxim-methyl in Landmark come into their own and provide superior disease control.

He attributed the difference to the formulation of Opus. &#42