Arbuscular Mycorrhizal Fungi Enhance Growth and Increase Concentrations of Anthocyanin, Phenolic Compounds, and Antioxidant Activity of Black Rice (Oryza sativa L.)

Abstract

Black rice (Oryza sativa L.) contains high concentrations of bioactive compounds that are associated with human-health benefits. Arbuscular mycorrhizal fungi (AMF) can increase plant performance and concentrations of these bioactive compounds. In a pot experiment, the effects of four different species of AMF (Claroideoglomus etunicatum; Rhizophagus variabilis; Rhizophagus nov. spec.; Acaulospora longula) were assessed on growth performance, grain yield, concentrations of phenolic compounds and anthocyanin, and antioxidant activity of two black-rice cultivars. The experiment was a completely randomized factorial design with two factors, viz. cultivar (Niew Dam Hmong and Maled Phai) and treatment (four different species of AMF and two non-inoculated treatments, without and with mineral fertilizer). Results showed that cultivar, treatment, and their interaction were almost always significant sources of variation for both plant performance parameters and concentrations of bioactive compounds. Maled Phai showed higher performance and higher concentrations of phenolics and anthocyanins but lower antioxidant activity than Niew Dam Hmong. The non-inoculated treatment without mineral fertilizer showed the lowest performance. The non-inoculated treatment with mineral fertilizer resulted in larger root and shoot biomass than the mycorrhizal treatments, but grain yield was higher in the mycorrhizal treatments. Inoculation with R. variabilis resulted in the highest concentration of phenolics and anthocyanins. We conclude that R. variabilis was the best inoculum for increasing grain yield and bioactive compounds, especially in Maled Phai.

Accumulation of Health-Promoting Compounds in Upland Black Rice by Interacting Mycorrhizal and Endophytic Fungi

“…The upregulation of anthocyanin biosynthesis in black rice as a consequence of AMF symbiosis has also been reported by Tisarum et al [44] and Wangiyana et al [45]. A previous study on Maled Phai black rice cultivar has shown that AMF-inoculated plants exhibit higher productivity and concentrations of phytochemicals compared with non-mycorrhizal plants [14]. In the current study, the presence of AMF remarkably improved the root dry weight, grain weight, antioxidants, and anthocyanin, compared with non-inoculated plants.…”

“…The AMF used in this study were molecularly identified as Rhizophagus variabilis strain KS-02 [14]. They was obtained from the Mycorrhiza and Mycotechnology Laboratory, Department of Microbiology, Faculty of Science, Khon Kaen University, Thailand.…”

“…They was obtained from the Mycorrhiza and Mycotechnology Laboratory, Department of Microbiology, Faculty of Science, Khon Kaen University, Thailand. These fungi strongly promoted the growth of Maled Phai [14]. AMF soil inoculum was multiplied by the pot culture technique, using maize (Zea mays L.) as a host plant.…”

“…Mycorrhizal plants have a greater ability to acquire nutrients and soil water than non-mycorrhizal plants, resulting in increased plant fitness both under normal and adverse environmental conditions [13]. Previous studies reported the beneficial effects of AMF on the growth promotion of several plants, including rice (Oryza sativa) [14][15][16][17][18][19]. Endophytic fungi (EPF) live inside plant tissues or organs such as seeds, leaves, flowers, twigs, stems, and roots, but do not form a symbiotic interface, contrary to AMF.…”

Inoculation of black turtle beans (Phaseolus vulgaris) with mycorrhizal fungi increases the nutritional quality of seeds

“…The commercial Rhizophagus irregularis products have shown positive, but less consistent yield results, which are often contributed to inconsistencies in viable AMF spores in products that are stored and shipped over long distances (Corkidi et al., 2004; Faye et al., 2013; Salomon et al., 2022). In addition to the success of AMF inoculation in bolstering yield, additional benefits of AMF inoculation on plant nutritional quality include increases in mineral nutrient uptake (Chandrasekaran, 2020; Clark & Zeto, 2000), anthocyanin concentration (Avio et al., 2017; Baslam et al., 2011; Chiomento et al., 2019; Nacoon et al., 2023; Tisarum et al., 2019), and overall antioxidant activity across a range of vegetables and fruits (Hart et al., 2015; Mollavali et al., 2016; Toussaint et al., 2007). Increases in the mineral nutrient concentration of foods can improve public health by preventing nutrient deficiency which affects over 2 billion people worldwide (Tulchinsky, 2010).…”