Biological control against Alternaria solani

Early blight disease caused by Alternaria solani is one of the most important damaging diseases common in most plants from the family solanaceae. At present, the most practical way to control this disease is to use fungicides. Considering the importance of early blight disease and excessive consumption of chemical pesticides, this study aimed to evaluate the efficacy of non-toxic compounds (Mycorrhiza agent) in controlling the disease. In this study, the mycorrhizal fungi Glomus moseae, G. rubi and Scutellospora sp were extended on corn roots. Then the effects of these factors were monitored and evaluated on plant indices as well as on pathogenicity of the fungus Alternaria solani under greenhouse conditions. The results from greenhouse experiments suggested significant impacts of arbuscular mycorrhizal compounds in reducing wave spot disease of tomato. The best treatment on the height of the stems and roots of tomato, respectively, were Scutellospora with G. mousae + Scutellospora (growth increases of 30.86% & 19.05%), and the highest influence on fresh s (31.37% & 47.81%, respectively) of shoot and root was found with G. moseae. The treatment G. mousae + Scutellospora obtained the greatest root dry weight (40.79% & 52.60%, respectively). The same treatment reduced the symptoms caused by the fungus A. solani up to 46.08%. Mycorrhizal treatments, therefore, are very effective on tomato growth increase and reduced disease severity by A. solani fungus, and can be a suitable choice to replace chemical pesticides yielding completely organic products.