ChileanJAR

An experiment was carried out to determine systemic action, ascendent and descendent translocation as well as persistence of the new fungicides Benlate (benomyl), EL-273 (triarimol), Sclex (dichlozoline), Cercobin M (metyltiophanate), CELA W524 (triforine) and Tecto 40 (thiabendazole).
Sunflower (Helianthus annuus L.), grown under greenhouse conditions, was the test plant.
Bioassay evaluation using Sclerotinia sclerotiorum (Lib.) de Bary as the pathogen was made through agar plate diffusion test. Persistence of the fungicides applied into the soil, was also evaluated through artificialinoculation of sunflower plants at flower- bud stage, using toothpicks infested with the fungus.
For studying ascendent translocation and persistence in the plants only one rate of the fungicide was applied to the soil at seeding time, and for observe descendent movement, each fungicide was sprayed, at one rate, over the apical leaves during the flower-bud stage.
All fungicides showed upward movement. Persistence varied with diferent como pounds when appliedto soil, ranging between 15 and 70 days. Benlate, Cercobin M and Sclex had a 70 days persistenee both in roots and Stem. However, Cercobin M and Teeto 40 exhibited deseendent transloeation and persistenee in stem tissues up to 10 and 20 days after applieation, respeetively.
Benlate and Cereobin M controlled S. sclerotiorum satisfactorily in vivo, under greenhouse eonditions, thus confirming previous results on their persistenee in stems.