Cowpea resistance induced against Fusarium oxysporum f. sp. tracheiphilum by crustaceous chitosan and by biomass and chitosan obtained from Cunninghamella elegans

Publication date: January 2016 Source:Biological Control, Volume 92 Author(s): Lúcia Raquel Ramos Berger, Newton Pereira Stamford, Lilia Gomes Willadino, Delson Laranjeira, Marcos Antonio Barbosa de Lima, Samuel Marcus Montarroyos Malheiros, Wanderson José de Oliveira, Thayza Christina Montenegro Stamford Pathogenic microorganisms increase the production of reactive oxygen species (ROS), and the response can cause oxidative damage and even death in a plant. Plant resistance inducers activate antioxidant enzymes such as catalase (CAT) and peroxidase (POX). The aims of this study were to evaluate the antimicrobial activity and the potential to induce the CAT and POX activities by the biopolymer chitosan in cowpea plants inoculated with the phytopathogen Fusarium oxysporum f. sp. tracheiphilum. The antimicrobial activity of crustaceous chitosan (CrCh) was tested in a laboratory assay and analyzed by optic and scanning electron microscopy. In a greenhouse experiment, the effectiveness of CrCh, fungal chitosan obtained from Cunninghamella elegans (C.eCh), and C. elegans biomass (C.eCh source) plus NPK biofertilizer, named bioprotector (C. elegans +NPKB), were evaluated in relation to the disease severity and the CAT and POX activities in cowpea plants infected with F. oxysporum f. sp. tracheiphilum. The higher rates of CrCh (4.0–6.0mgmL−1) showed the total fungicide ability, and the other concentrations (0.5–3.0mgmL−1) promoted a greater fungistatic e...
Source: Biological Control - Category: Biology Source Type: research