Effect of Salicylic acid (SA) against the fungus Macrophomina phaseolina (Tassi) Goid and development of charecoal Rot disease on Sunflower Helainthus annus L.

The aim of the study was to evaluate the different concentration of Salicylic acid (SA)against the phytopathogenic fungus Macrophomina phaseolina (Tassi) Goid the causal of charcoal Rot disease on Sunflower plants . The result showed that the inhibitory effect of (SA) on development of M. phaseolina increased linearly with increasing concentration, the colony diameter reduced to 4.6, 1.2 cm at 200, 250 mg\ L respectively. The same concentration of (SA) inhibited the germination of sclerotia to 66.67%, 26.67% respectively. The result showed that the different treatment of (SA) were effective in reducing the disease infection significantly the least infection was 16.96% when 250 mg \ L of (SA) was applied while at control was 64.6%. Result indicate that (SA) at 200, 250 mg\L increased dry weight of shoot to 0.336, 0.363 gm respectively and dry weight of root to 0.056, 0.063 gm respectively compared to control ones which is 0.24, 0.039 gm respectively and reduced the number of sclerotia which was 27.2, 20.1 sclerotial \ gm of Rhizosphere soil compared to control which is 49.2 sclerotial \ gm soil. [ABSTRACT FROM AUTHOR]