الفهرس 
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Abstract
Rhizoctonia solani, the most widely recognized species of Rhizoctonia was originally described by Julius Kühn on potato in 1858. R. solani is a very common Soil-borne pathogen with a great diversity of host plants. Rhizoctonia solani can survive for many years by producing small (1 to 3 mm diameter), irregular-shaped, brown to black structures (called sclerotia) in soil and on plant tissue. In this work, the results of testing of hematoporphyrins as photofungicides, which have been already approved for medical use in the photodynamic therapy of tumors and other disease. HP becomes toxic only when it is activated by light. We used natural and artificial light with porphyrine derivative and laser radiation for controlling R. solani Hematoporphyrine (IX) possesses several favorable features for such application as photofungicide due to the it is endowed a high quantum yield for generation of highly cytotoxic intermediatesit absorbs essentially all wavelengths in the sun emission spectrumit typically acts at the level of cell membranes minimizing the induction of mutagenic effectsit has high photosensitizing activity towards biological systems in addition, its already approval for medical use in photodynamic therapy of tumors and other disease The efficiency of the photosensitization reaction depends on the concentration of HP, the fluence rate of irradiation and exposure time. The results reveal that, the sclerotia of R solani treated with lowest concentration of HP and photoirradiated by solar simulator at highest intensity rate was exhibited 100% mortality during exposure time (3 hours But the highest concentration was more efficient when the sample, which exposed to direct sunlight, was found that the survival percentage of linear growth of R solani was zero % when irradiation at sunlight for 4 hour (fluence rate 504 W/m2) after treatment with concentration 10-2 mol dm-3 of HP It is found that the average solar irradiation in a sunny day in Cairo is about 650 W/m2 and 250 W/m2 in summer and winter respectively. On the other hand the laser radiation reaction depends on the exposure time and power of radiation, as shown in the results the mortality increased by increase of the exposure time and the power radiation.