Chemistry Research Journal, 2018, 3(4):105-109 Chemistry Research Journal 105 Available online www.chemrj.org Research Article ISSN: 2455-8990 CODEN(USA): CRJHA5 Antifungal activity of alcoholic extract of Juglans regia against phytopathogenic Rhizoctonia solani Mohammed Nadeem Kasim Hantoosh 1 , Hussein Ali Salim* 2 , Emad Adnan Mahdi 1 , Hassan Ali Majid 1 , Mohammed Abdalrahem Jalal 1 1 College of Agriculture, University of Diyala, Iraq 2 Directorate of Diyala Agriculture, Ministry of Agriculture, Iraq Abstract A current study was conducted at University of Diyala, College of Agriculture, during 9\2016-3\2017 to evaluate in-vitro different concentrations (5, 10, 15 and 20%) of the stem bark of Juglans regia L. against three isolates of phytopathogenic fungi Rhizoctonia solani were isolated from (cauliflower ,tomato and eggplant) through poisoned food technique. The findings showed that fungal growth of three R. solani isolates were decreased with increasing of J. regia concentration with significantly differences between them, a minimum of mycelia growth of three isolates of R. solani was 3.5 cm at 5% concentration and decreased gradually to 0.4 cm at 20% concentration, R. solani isolates were showed significant differences in radial growth, R. solani (Eggplant) was susceptible to all concentrations from other isolates in radial growth (2.1 cm) followed by R. solani (Tomato) 3.5 cm and R. solani (cauliflower) 3.9 cm whereas data further exhibited a significant interaction between concentrations of J. regia with isolates of R. solani, all of the tested concentrations were inhibited the growth of pathogen strains, % inhibition of R. solani growth were 94.8% at concentration 20% followed by 90.7, 75.9 and 60.7% at concentrations (15, 10 and 5%) respectively, inhibition percentage of different R. solani isolates were with variable degrees of sensitivity to concentrations of Juglans regia (76.6, 60.4, 56.2%.) at (R. solani, Eggplant), (R. solani, Tomato) and (R. solani, cauliflower) respectively, a significant interaction between concentrations (10, 15 and 20 %) of J. regia with isolates of R. solani were most effective to suppressed mycelia growth of all the R. solani strains that recorded 100%.The concentrations of 10, 15 and 20 % were most effective to restrict the growth of all the pathogen isolates that recorded 100% in inhibition percentage of radial growth of R. solani (Tomato) and R. solani (Eggplant). Keywords Juglans regia, Rhizoctonia solani, poisoned food technique Introduction Rhizoctonia solani is soil-borne fungus that causes losses in many crops [1]. R. solani causing several of seedlings diseases with high losses of up to 80–100% [2,3,4]. R. solani cause necrosis of root, cortex tissue, root rot, damping- off, subsequent death [5]. Chemical pesticides application have hazardous impacts of including problems of environmental pollution, public health, causing resistance in disease agents and toxic effect on no target organisms, In spite of synthetic pesticides are the most effective method of the disease control [6,7]. There are environmentally safe methods are needed to replace or reduce chemical pesticides. Biocides are easily biodegradable and environmentally safe [8]. Some of plants was containing natural antimicrobial compounds[9,7]. Several works have demonstrated in laboratory trials that different plant tissues, such as leaves, roots, flowers and seeds possess