Comparative physiological and soil microbial community structural analysis revealed that selenium alleviates cadmium stress in Perilla frutescens

Abstract

Cadmium (Cd) toxicity not only affects plant growth and development, but also affects human health through the food chain. Several studies have demonstrated that Selenium (Se) alleviates Cd stress in plants; however, whether and how Se-alleviated Cd stress by regulating the structure of soil microbial community remain largely unclear. Here, we investigated the alleviating effects of exogenous applied Se (foliar spraying or root application) on plant growth under Cd stress in perilla (Perilla frutescens L.) by measuring the biomass, photosynthetic fluorescence parameters, root cell wall components and soil microbial community structure and diversity. Under Cd stress, perilla seedlings supplemented with Se increased chlorophyll content. Foliar spraying Se increased the levels of relative chlorophyll content (ΦII), photosynthetic system II (ΦPSII) and electron transport rate (ETR) in perilla leaves under Cd stress; while, root application of Se increased the levels of photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), water use efficiency (WUE) and stomatal limitation value (Ls) under Cd stress. Compared with Cd toxicity alone, root application of Se increased the contents of hemicellulosic 1 and hemicellulosic 2 in the cell wall of perilla roots. Cd toxicity or root application of Se did not affect soil bacterial community diversity. Root application of Se increased the relative abundance of Proteobacteria, Bacteroidetes, Fibrobacteres, Sphingomonas and Nitrosospira in Cd-contaminated soil, and thereby improving soil microbial community structure, finally promoting the growth of perilla seedlings.

Application of Selenium Can Alleviate the Stress of Cadmium on Rapeseed at Different Growth Stages in Soil

“…Studies have shown that treatment with Se alters the structural composition of soil microbial communities but does not have a significant impact on the diversity of soil bacterial microbial communities. Proteobacteria and Bacteroidetes decreased under Cd toxicity, whereas they increased after applying Se in [38], which is consistent with the results of this study. Proteobacteria and Bacteroidetes are involved in the degradation of organic matter and the biotransformation of mineral elements and play a role in the degradation of macromolecular organic matter in soil.…”

Variation of microbiological and small molecule metabolite profiles of Nuodeng ham during ripening by high-throughput sequencing and GC-TOF-MS

“…The relative abundance of Sphingomonas was positively correlated with L-proline, hydroxyisocaproic acid, xanthine, pantothenic acid and L-arginine (P < 0.05). Sphingomonas had extensive metabolic capacity for aromatic compounds and could promote the production of many metabolites [51] . The relative abundance of Bacillus was positively correlated with the content of inosine (P < 0.05).…”

Application of Selenocysteine Increased Soil Nitrogen Content, Enzyme Activity, and Microbial Quantity in Camellia oleifera Abel. Forests

“…The common inorganic Se is mainly elemental Se (Se 0 ), selenide (Se 2− ), selenite (Se 4+ ), and selenate (Se 6+ ); organic Se is mainly represented by selenocysteine and selenomethionine [4]. In recent years, studies on inorganic Se have been reported in many aspects, such as the effects of Se on crop growth and absorption [5,6], the interaction between Se and metals on plants or soils [7][8][9], and the morphology and transformation of Se in the soil [10]. To date, the application of inorganic Se (selenite and selenate) to the soil as Se fertilizer has become the norm [11].…”

“…Liu et al [20] found that selenite would be transformed into a stable and low-toxicity state in the soil, increase persistent free radicals, and thus reduce the abundance and diversity of microorganisms. Yang et al [7] showed that root application of Se could increase the bacterial abundance in cadmium-contaminated soil and improve the soil microbial community structure. Cheng et al [21] showed in a pot experiment of rapeseed that Se application could contribute to the enrichment of beneficial rhizosphere microorganisms in rapeseed rhizosphere soil, thus promoting plant growth.…”