Elevation of Systemic Defense in Potato Against Alternaria Solani by a Consortium of Compatible Trichoderma Spp.

Abstract The crop loss due to phytopathogens is a serious problem affecting the entire world. To avoid economic losses due to phytopathogens synthetic chemicals have been used for years generating serious concerns about the human health and environment. Today the use of beneficial microorganisms to treat phytopathogens is gaining attention. In this way, Trichoderma spp. has been used for combating plant diseases and inducing defense response in plants. With this idea in mind, in this study we evaluate the effectiveness of Trichoderma viride and T. harzianum as single as well as in combination for elevating the defense response and growth promotion activities in potato challenged with Alternaria solani. The mycelial inhibition of A. solani by T. viride and T. harzianum was recorded and compared with control. Scanning electron microscope (SEM) observation revealed the collapsed hyphae and sunken conidia of A. solani due to antagonistic activity of T. viride and T. harzianum. Induction of defense enzymes including TPC, PAL, SOD and total protein content was increased in Trichoderma spp, treated plants as compared with pathogen inoculated plants. HPLC analysis demonstrated higher production in phenolic compounds during combined application of Trichoderma spp. treated potato plants in the response of A. solani infection. Moreover, treatment with Trichoderma spp. consortium showed significant growth promotion in potato plants comparing with the control.