Seed-applied bioprotectants for control of seedborne Alternaria arborescens and growth enhancement of wheat

Abstract: Alternaria arborescens was recently detected as a new member of the Alternaria spp. complex causing black point in Argentina. Seed treatments with Trichoderma harzianum and Epicoccum nigrum; Lippia alba and garlic extracts; sodium bicarbonate (SB), salicylic acid (SA), potassium chloride (PC) and sodium phosphate dibasic (SP) were applied to grains of wheat cv BIOINTA 1004 previously to the infection with the pathogen following ISTA (blotter method) rules. After 7 days, seed germination, infected seeds, necrotic symptoms of emerged seedlings and fresh weight were evaluated. Remarkable results were obtained with L. alba, SA and SP that reduced symptoms from 50 to 78% compared with the control. Necrosis of radicles was significantly reduced by the application of all treatments tested. Moreover, fresh weight of seedlings was significantly increased with the application of the two antagonists, garlic and the three tested salts in comparison with control. It is concluded that compounds here tested have potential as biofertilizers and ecofriendly alternatives to control seed-borne fungi of wheat.