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The effect of five different organic and systemic fungicides (Zineb,Captan, PCNB, PCNB+ Terrazol, Benomyi)on respiration rate of the mycelium of Sclerotinia sclerotiorum was studied.
This research was performed on the myceliums isolated from the collar of
sunflower plant,then cultivated on solid and shaking liquid media. The effect of
1/1000dose of each fungicide on the respiration rate of myceliums after 24 hours exposure was measured using the Warburg—Bar croft apparatus (Manometric technique).
The results showed that the fungicides can he catagorized in two different groups concerning their effects on the respiration rate of myceliums.Some of them such as Zineb,Captan and PCNB+ Terrezol decreased the respiration rate,whereas,the others such as PCNB and Benomyl had either no effect or in some cases caused an increase of the respiration rate.