Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease ca...Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P1 to improve plant growth of locally important horticultural crops: lettuce, tomatoes and peppers and to prevent disease in the greenhouse and field. The effect of the Trichoderma treatment was evaluated by determining the weight of fresh and dry roots and above ground plant biomass, measuring plants height, counting the number of emerged leaves (lettuce, tomatoes and peppers) and quantifying production (tomatoes and peppers). No disease symptoms were found during production, although Fusarium sp. strains pathogenic to tomato were detected in the soil. Compounds containing copper oxychloride are frequently used for fungal disease control in agriculture. In order to investigate the compatibility of T. harzianum T22 and T. atroviride P1 with copper oxychloride applications, the effect on mycelia growth was monitored in both liquid and solid medium. In general, the tests indicated a high level of tolerance of the Trichoderma strains to concentrations of copper oxychloride varying from 0.1 to 5 mmol/L.展开更多
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soi...Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere mi-croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial bio-technology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.展开更多
文摘Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P1 to improve plant growth of locally important horticultural crops: lettuce, tomatoes and peppers and to prevent disease in the greenhouse and field. The effect of the Trichoderma treatment was evaluated by determining the weight of fresh and dry roots and above ground plant biomass, measuring plants height, counting the number of emerged leaves (lettuce, tomatoes and peppers) and quantifying production (tomatoes and peppers). No disease symptoms were found during production, although Fusarium sp. strains pathogenic to tomato were detected in the soil. Compounds containing copper oxychloride are frequently used for fungal disease control in agriculture. In order to investigate the compatibility of T. harzianum T22 and T. atroviride P1 with copper oxychloride applications, the effect on mycelia growth was monitored in both liquid and solid medium. In general, the tests indicated a high level of tolerance of the Trichoderma strains to concentrations of copper oxychloride varying from 0.1 to 5 mmol/L.
文摘Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere mi-croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial bio-technology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.
