Malus Antioxidant Metabolism Following Bacterial–Fungal Inoculation in Organic Farming: From Root to Fruit

This study investigated the antioxidant status of roots, leaves, and fruit upon microbial inoculation (AMF+PGPR, arbuscular mycorrhizal fungi, and plant growth-promoting rhizobacteria, respectively) of young organically farmed apple trees over two growing seasons. Three cultivars—‘Topaz’, ‘Chopin’, and ‘Odra’—were selected to test the relationship between inoculation and enzymatic and non-enzymatic antioxidant components. The antioxidant metabolism was highly dependent on tissue type and growing season. The greatest effect on antioxidant status following application of the inoculum was found in roots, then leaves, but it was almost negligible in fruit. Roots were influenced most by application of the inoculum in the first growing season, while leaves were influenced most in the second season. Considerable differences between the inoculated and control plants were found for root glutathione reductase (GR) and catalase (CAT) activity, as well as glutathione and ascorbate contents; root phenolics were not influenced by inoculation. In the case of leaves, effect of microbial inoculation on GR activity was revealed in the first growing season, while for global phenolics in the second season, and only the concentration of glutathione was significantly higher in the leaves of inoculated trees in both growing seasons. Leaf ascorbate content and CAT activity were not influenced by the microbial inoculation. The control and inoculated trees expressed a similar total antioxidant capacity, irrespective of the tissue type tested. Furthermore, the response of the cultivars to inoculation varied and also changed in consecutive growing seasons. Based on this study, it is likely that the effect of microbial inoculum as a tool for enhancing health-promoting properties in the fruit of perennial plants is weaker than that described for vegetables where different plant organs are edible.

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Towards a Sustainable Agriculture: Strategies Involving Phytoprotectants against Salt Stress

Agronomy ◽

10.3390/agronomy10020194 ◽

2020 ◽

Vol 10 (2) ◽

pp. 194 ◽

Cited By ~ 1

Author(s):

José Ramón Acosta-Motos ◽

Consuelo Penella ◽

José A. Hernández ◽

Pedro Díaz-Vivancos ◽

María Jesús Sánchez-Blanco ◽

...

Keyword(s):

Salt Stress ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Plant Growth Promoting Rhizobacteria ◽

Antioxidant Metabolism ◽

Water Demands ◽

Industrial Sectors ◽

Treatment Conditions ◽

Plant Growth Promoting ◽

Related Compounds

Salinity is one of the main constraints for agriculture productivity worldwide. This important abiotic stress has worsened in the last 20 years due to the increase in water demands in arid and semi-arid areas. In this context, increasing tolerance of crop plants to salt stress is needed to guarantee future food supply to a growing population. This review compiles knowledge on the use of phytoprotectants of microbial origin (arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria), osmoprotectants, melatonin, phytohormones and antioxidant metabolism-related compounds as alleviators of salt stress in numerous plant species. Phytoprotectants are discussed in detail, including their nature, applicability, and role in the plant in terms of physiological and phenotype effects. As a result, increased crop yield and crop quality can be achieved, which in turn positively impact food security. Herein, efforts from academic and industrial sectors should focus on defining the treatment conditions and plant-phytoprotectant associations providing higher benefits.

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Effect of Lime, Compost and Microbial Inoculants on Micronutrient Removal by Mustard and Maize in Trace Metal Contaminated Soil of Jharkhand

Current Agriculture Research Journal ◽

10.12944/carj.5.2.07 ◽

2017 ◽

Vol 5 (2) ◽

pp. 196-199

Author(s):

Amrit Kumar Jha

Keyword(s):

Trace Metal ◽

Contaminated Soil ◽

Mycorrhizal Fungi ◽

Metal Removal ◽

Cropping System ◽

Arbuscular Mycorrhizal ◽

Plant Growth Promoting Rhizobacteria ◽

Microbial Inoculants ◽

Microbial Inoculation ◽

Plant Growth Promoting

A field experiment was conducted on trace metal contaminated soil at Patratu (Ramgarh) to study the effect of lime, compost, plant growth promoting rhizobacteria and arbuscular mycorrhizal fungi on micronutrient removal viz. Zn, Cu, Mn and Fe in mustard-maize cropping system. Results reveal that inoculation with Glomus mossae, Pseudomonas striata and Azotobacter chroococcum increased Zn concentration to the extent 13 to 32, 10 to 24 and 9 to 24 (%), respectively over control. Copper, manganese and iron uptake followed almost similar trend as that of Zn. Microbial inoculants with or without vermicompost increased the trace metal removal, however, vermicompost alone decreased the removal. It was observed that microbial inoculations reduced the total Zn, Cu, Mn and Fe content in soil. However, available micronutrients were significantly reduced by microbial inoculation and amendments.

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The Effect of Microbial Inoculation under Various Nitrogen Regimes on the Uptake of Nutrients by Apple Trees

Agronomy ◽

10.3390/agronomy11112348 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2348

Author(s):

Kamila Łucja Bokszczanin ◽

Dariusz Wrona ◽

Sebastian Przybyłko

Keyword(s):

Nutritional Status ◽

Mycorrhizal Fungi ◽

Negative Impact ◽

Arbuscular Mycorrhizal ◽

Plant Growth Promoting Rhizobacteria ◽

Negative Influence ◽

Microbial Inoculation ◽

Plant Growth Promoting ◽

Nitrogen Treatment ◽

Leaf P

The European Green Deal strategy currently implemented in the EU aims to, among others, reduce the negative impact of fertilization on the environment. One of the solutions influencing the nutritional status of plants and the improvement of soil quality is the use of plant symbiosis with microorganisms. Thus, in this study we investigated the effect of arbuscular mycorrhizal fungi (AMFs) and plant-growth-promoting rhizobacteria (PGPR) colonization on the nutritional status of apple leaves and fruit, depending on the nitrogen treatment. In a fully factorial experiment, trees were grown for nine years with or without AMFs and PGPR. We compared several ammonium nitrate treatments as well as growth without fertilization as a control. The interactions between inoculation and doses of nitrogen fertilization were observed. AMF + PGPR significantly increased the concentration of nitrogen (N), phosphorus (P), and potassium (K) in leaves up to 5%, 23%, and 19%, respectively, depending on the N dosage. Conversely, in uninoculated trees, the nitrogen treatment had a negative impact on the leaf P mineral status. On the other hand, under microbial inoculation conditions, the dose of 100 kg N∙ha−1 diminished the leaf phosphorus content in comparison to other N doses, by a maximum of 9.6%. AMF + PGPR, depending on the N treatment, either did not influence or it decreased the Mg and Ca concentrations in the leaves by maximums of 8% and 15%, respectively. Microbial inoculation had no effect on the acquisition of Ca and Mg by fruits, except for the coupled negative influence of the 100 kg N∙ha−1 treatment. Symbiosis positively conditioned the K in fruits under a specific N regime—100 kg N∙ha−1 divided into two applications during the season and 50 kg N∙ha−1 applied to the herbicide strip, increasing the concentration by approximately 4% and 8%, respectively. This study greatly contributes to our understanding of the benefits of AMF and PGPR on perennials and encourages the future exploration of their effects on apple yield and fruit quality.

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Plant Growth-Promoting Microorganisms in Coffee Production: From Isolation to Field Application

Agronomy ◽

10.3390/agronomy11081531 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1531

Author(s):

Narcisa Urgiles-Gómez ◽

María Eugenia Avila-Salem ◽

Paúl Loján ◽

Max Encalada ◽

Leslye Hurtado ◽

...

Keyword(s):

Plant Growth ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Plant Growth Promoting Rhizobacteria ◽

Agroforestry Systems ◽

Field Application ◽

Coffee Production ◽

Coffee Agroforestry ◽

Plant Growth Promoting ◽

Growth Promoting

Coffee is an important, high-value crop because its roasted beans are used to produce popular beverages that are consumed worldwide. Coffee plantations exist in over 70 countries and constitute the main economic activity of approximately 125 million people. Currently, there is global concern regarding the excessive use of agrochemicals and pesticides in agriculture, including coffee crops. This situation has motivated researchers, administrators, and farmers to seek ecologically friendly alternatives to decrease the use of synthetic fertilizers and pesticides. In the last decades, multiple studies of the rhizosphere, at the chemical, physical and biological levels, have improved our understanding of the importance of beneficial microorganisms to plant health and growth. This review aims to summarize the state of the use of plant growth-promoting microorganisms (PGPM) in coffee production, where the most extensively studied microorganisms are beneficial plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF). This review also contains information on PGPM, in regard to plantations at different latitudes, isolation techniques, mass multiplication, formulation methods, and the application of PGPM in nurseries, monoculture, and coffee agroforestry systems. Finally, this review focuses on relevant research performed during the last decade that can help us improve sustainable coffee production.

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The Effect of Mycorrhizal Inoculum and Phosphorus Treatment on Growth and Flowering of Ajania (Ajania pacifica (Nakai) Bremer et Humphries) Plant

Horticulturae ◽

10.3390/horticulturae7070178 ◽

2021 ◽

Vol 7 (7) ◽

pp. 178

Author(s):

Matej Vosnjak ◽

Matevz Likar ◽

Gregor Osterc

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Flowering Time ◽

Endophytic Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Growing Season ◽

Shoot Length ◽

Available Phosphorus ◽

Growing Seasons ◽

Number Of Shoots

The influence of mycorrhizal inoculum in combination with different phosphorus treatments on growth and flowering parameters of Ajania (Ajania pacifica (Nakai) Bremer et Humphries) plants was investigated in two growing seasons (2015 and 2016). Plants of the cultivar ‘Silver and Gold’ were transplanted into pots either with added mycorrhizal inoculum or without inoculum and assigned to four phosphorus treatments. Mycorrhizal colonization was assessed by evaluating the frequency of colonization, intensity of colonization and density of fungal structures (arbuscules, vesicles, coils and microsclerotia) in the roots. During the growing season, the content of plant available phosphorus in the soil was analyzed, and shoot length, number of shoots, number of inflorescences, number of flowers and flowering time were evaluated. Inoculated Ajania plants were successfully colonized with arbuscular mycorrhizal fungi and dark septate endophytic fungi. In the root segments, hyphae were mainly observed, as well as vesicles, coils, arbuscules and microsclerotia, but in lower density. The density of fungal structures did not differ among phosphorus treatments, but did differ between years, with a higher density of fungal structures in 2016. Mycorrhizal plants developed higher number of shoots in 2016, higher number of inflorescences, higher number of flowers, and they flowered longer compared to uninoculated plants.

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