Azospirillum Sp245 was tested for its ability to control prunus seedlings damping-off caused by Rhizoctonia solani during acclimatation, in which plants are very vulnerable to phytopathogens. The rooted seedlings at the time of transplantation in peat become possible hosts of fungal agents such as Rhizoctonia solani, which is one of the major responsible for damping-off and root rot diseases (Matta, 1996). In this perspective the use of systemic fungicides to protect plants against these pathogens is widely necessary. A sustainable alternative can be represented by rhizobacteria of the genus Azospirillum that have been extensively used as inoculum for crop phytostimulation thanks to their positive interaction with plants at root level (Dobbeleare et al., 2001; Russo et al., 2005). Azospirillum brasilense Sp245 is a motile, free-living, Gram-negative bacterium that occur in the soil, capable of nitrogen fixation, phytohormone production, particularly indole acetic acid (IAA), and an auxin-like molecule production, identified as phenylacetic acid (PAA) (Somers et al., 2005). This last molecule, seems to be involved in the biocontrol activity of the bacterium; thus, suggesting A. brasilense use not only for phytostimulation but also for plant protection. In vitro/in vivo tests and DGGE analysis has been carried out to evaluate beneficial effects of Sp245. Beside the positive effects of Sp245 inoculum on the micropropagation of plum Prunus cerasifera L. clone Mr.S 2/5, the biocontrol activity against Rhizoctonia spp. infection has been demonstrated in vitro evaluating the inhibition played by Azospirillum in the development of mycelium of Rhizoctonia solani and in vivo by means Mr.S 2/5 plants infected by Rhizoctonia spp. The biocontrol effect of Sp245 on rhizospheric fungi and particularly on R. solani has been confirmed by DGGE profiles of the rhizosferic microbial community
Biocontrol activity of Azospirillum brasilense Sp245 against Rhizoctonia solani by in vitro/in vivo tests, DGGE analysis
MORINI, STEFANO;TOFFANIN, ANNITA;
2010-01-01
Abstract
Azospirillum Sp245 was tested for its ability to control prunus seedlings damping-off caused by Rhizoctonia solani during acclimatation, in which plants are very vulnerable to phytopathogens. The rooted seedlings at the time of transplantation in peat become possible hosts of fungal agents such as Rhizoctonia solani, which is one of the major responsible for damping-off and root rot diseases (Matta, 1996). In this perspective the use of systemic fungicides to protect plants against these pathogens is widely necessary. A sustainable alternative can be represented by rhizobacteria of the genus Azospirillum that have been extensively used as inoculum for crop phytostimulation thanks to their positive interaction with plants at root level (Dobbeleare et al., 2001; Russo et al., 2005). Azospirillum brasilense Sp245 is a motile, free-living, Gram-negative bacterium that occur in the soil, capable of nitrogen fixation, phytohormone production, particularly indole acetic acid (IAA), and an auxin-like molecule production, identified as phenylacetic acid (PAA) (Somers et al., 2005). This last molecule, seems to be involved in the biocontrol activity of the bacterium; thus, suggesting A. brasilense use not only for phytostimulation but also for plant protection. In vitro/in vivo tests and DGGE analysis has been carried out to evaluate beneficial effects of Sp245. Beside the positive effects of Sp245 inoculum on the micropropagation of plum Prunus cerasifera L. clone Mr.S 2/5, the biocontrol activity against Rhizoctonia spp. infection has been demonstrated in vitro evaluating the inhibition played by Azospirillum in the development of mycelium of Rhizoctonia solani and in vivo by means Mr.S 2/5 plants infected by Rhizoctonia spp. The biocontrol effect of Sp245 on rhizospheric fungi and particularly on R. solani has been confirmed by DGGE profiles of the rhizosferic microbial communityI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
