Plant parasitic nematodes are important pathogens of many field, horticultural- and fiber-crops and without appropriate control they may cause significant losses of both yield and quality. The effective management of diseases caused by nematodes is multifactorial, however at the present in most crops it heavily relies on the use of chemical nematocides to maintain the nematode populations below economic threshold levels. However, chemical control is costly and poses safety and environmental concerns, therefore suppression of plant parasitic nematodes with predators, parasites or disease agents is a desirable alternative to chemicals. Soil fungi belonging to the genus Trichoderma have long been known to be a feasible biological alternative to chemicals for control of several soil-borne plant pathogen and are also known for their ability to enhance plant growth (Druzhinina et al., 2011). Studies have shown that Trichoderma spp. have a potential also for biological control of plant parasitic nematodes. We have investigated the three-way interaction between one antagonistic strain of Trichoderma harzianum and the root-knot nematode Meloidogyne incognita on susceptible tomato plants in a pot experiment. Tomato germlings were seeded in clay pots containing sterile river sand and subsequently treated with a conidia suspension of Trichoderma, to reach the density of 107 CFU/g of soil. Plants were grown in a growth chamber for ten days, then inoculated with M. incognita juveniles (J2) and grown for 40 days. The amount of J2 which were able to establish feeding site and develop into the roots, as well as nematode reproduction, were lower if plants were pre-treated with fungi. To obtain new insights into the events underlining the processes of plant-nematode-Trichoderma interactions, we identified and characterized a set of systemic induced resistance genes normally activated in a wide range of different defensive traits. These processes are possible because plants and microorganisms can communicate with each other through various signalling mechanisms. Depending on the kind of pathogen, the plant strongly activate those signalling pathway that are most efficient in suppressing the intruder. Changes in gene expression of tomato plants (Cai et al, 2013) treated with Trichoderma and infected with M. incognita are under further investigation in the perspective of a practical use of fungi as an effective and safe alternative to chemical control. Reference: "Trichoderma: the genomics of opportunistic success". I.S. Druzhinina, et al.; Nature Review Microbiology (2011). "Harzianolide, a novel plant growth regulator and systemic resistance elicitor from T. harzianum". Feng Cai et al.; PPB 73 (2013) 106-113. This research was carried out within the project CISIA, sub-project SOS-POM, funded by the National Research Council (CNR) of Italy
How fungi interact with nematode to activate the plant defence response in tomato plants
Leonetti P;Zonno M;
2014
Abstract
Plant parasitic nematodes are important pathogens of many field, horticultural- and fiber-crops and without appropriate control they may cause significant losses of both yield and quality. The effective management of diseases caused by nematodes is multifactorial, however at the present in most crops it heavily relies on the use of chemical nematocides to maintain the nematode populations below economic threshold levels. However, chemical control is costly and poses safety and environmental concerns, therefore suppression of plant parasitic nematodes with predators, parasites or disease agents is a desirable alternative to chemicals. Soil fungi belonging to the genus Trichoderma have long been known to be a feasible biological alternative to chemicals for control of several soil-borne plant pathogen and are also known for their ability to enhance plant growth (Druzhinina et al., 2011). Studies have shown that Trichoderma spp. have a potential also for biological control of plant parasitic nematodes. We have investigated the three-way interaction between one antagonistic strain of Trichoderma harzianum and the root-knot nematode Meloidogyne incognita on susceptible tomato plants in a pot experiment. Tomato germlings were seeded in clay pots containing sterile river sand and subsequently treated with a conidia suspension of Trichoderma, to reach the density of 107 CFU/g of soil. Plants were grown in a growth chamber for ten days, then inoculated with M. incognita juveniles (J2) and grown for 40 days. The amount of J2 which were able to establish feeding site and develop into the roots, as well as nematode reproduction, were lower if plants were pre-treated with fungi. To obtain new insights into the events underlining the processes of plant-nematode-Trichoderma interactions, we identified and characterized a set of systemic induced resistance genes normally activated in a wide range of different defensive traits. These processes are possible because plants and microorganisms can communicate with each other through various signalling mechanisms. Depending on the kind of pathogen, the plant strongly activate those signalling pathway that are most efficient in suppressing the intruder. Changes in gene expression of tomato plants (Cai et al, 2013) treated with Trichoderma and infected with M. incognita are under further investigation in the perspective of a practical use of fungi as an effective and safe alternative to chemical control. Reference: "Trichoderma: the genomics of opportunistic success". I.S. Druzhinina, et al.; Nature Review Microbiology (2011). "Harzianolide, a novel plant growth regulator and systemic resistance elicitor from T. harzianum". Feng Cai et al.; PPB 73 (2013) 106-113. This research was carried out within the project CISIA, sub-project SOS-POM, funded by the National Research Council (CNR) of ItalyI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
