he olive trees had been suffering from attacks by a problem commonly known as Olive Leaf Spot (OLS) or Peacock Spot Disease caused by Spilocea oleaginea. The fungus was isolated and identified from diseased olive leaves orchards which collected from Ismailia and Behira Governorates. Inoculation procedures were performed under aseptic conditions by spraying spore suspension of S. oleagina (2 x 104, 2 x 105 and 2 x 106 spores/mL). The fungus S. oleagina decreased a photosynthetic pigments (chlorophyll A, B and carotenoid) and carbohydrate contents in all infected olive leaves cultivars. Two fungicides are currently registered for the control of Peacock spot in olives. Amistar (40cm/L.w) and Copper oxychloride rate(.05g/200mL) .In vitro, different concentrations were prepared and tested for their efficiency and to include the active ingredient. Amistar at rates 0.04, 0.004, 0.0004, 0.00004 (cm/100mL media) as well as copper oxychloride at rates 0.5, 0.05, 0.005, 0.0005 (g/100mL media) were prepared and tested against linear growth rate and sporulation density of the tested fungus. In vivo, The recommended dose of each fungicide were used. Both fungicidal treatments received three sprays at 15-days interval. The first spray was done at the 1st of October of 2013. The foliage was carefully covered with the fungicidal solution. After 15 days from the last spray the trees were examined against the disease and the data were recorded for each treatment on the basis of the percentage and severity of leaf infection involved by the number of lesion. The two fungicides, Amistar and Copper oxychloride improved all chlorophyllA,B, carotenoid and carbohydrate contents in all infected olive leaves cultivars. |
