Wheat Rhizosphere Metagenome Reveals Newfound Potential Soil Zn-Mobilizing Bacteria Contributing to Cultivars’ Variation in Grain Zn Concentration

Frontiers in Microbiology

Zikang Guo¹  Yuwei Ren¹  Li Wang¹  Fan Jiang¹  Xingshu Wang¹  Hengchao Wang¹  Wei Fan²  Lijuan Yin²  Zhaohui Wang²  Bo Liu²  Sen Wang²  Conghui Liu²  Anqi Wang³  Yan Zhang⁴  Hangwei Liu⁴ 

[1] F University, Yangling, China;Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China;;Key Laboratory of Plant Nutrition and Agri-Environment in Northwest China, Ministry of Agriculture, College of Natural Resources and Environment, Northwest A&;State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&

关键词: wheat cultivar;    rhizosphere;    microbiome;    soil Zn mobilization;    bacteria;    Zn biofortification;   

DOI  :  10.3389/fmicb.2021.689855

来源: DOAJ

【 摘 要 】

An effective solution to global human zinc (Zn) deficiency is Zn biofortification of staple food crops, which has been hindered by the low available Zn in calcareous soils worldwide. Many culturable soil microbes have been reported to increase Zn availability in the laboratory, while the status of these microbes in fields and whether there are unculturable Zn-mobilizing microbes remain unexplored. Here, we use the culture-independent metagenomic sequencing to investigate the rhizosphere microbiome of three high-Zn (HZn) and three low-Zn (LZn) wheat cultivars in a field experiment with calcareous soils. The average grain Zn concentration of HZn was higher than the Zn biofortification target 40 mg kg–1, while that of LZn was lower than 40 mg kg–1. Metagenomic sequencing and analysis showed large microbiome difference between wheat rhizosphere and bulk soil but small difference between HZn and LZn. Most of the rhizosphere-enriched microbes in HZn and LZn were in common, including many of the previously reported soil Zn-mobilizing microbes. Notably, 30 of the 32 rhizosphere-enriched species exhibiting different abundances between HZn and LZn possess the functional genes involved in soil Zn mobilization, especially the synthesis and exudation of organic acids and siderophores. Most of the abundant potential Zn-mobilizing species were positively correlated with grain Zn concentration and formed a module with strong interspecies relations in the co-occurrence network of abundant rhizosphere-enriched microbes. The potential Zn-mobilizing species, especially Massilia and Pseudomonas, may contribute to the cultivars’ variation in grain Zn concentration, and they deserve further investigation in future studies on Zn biofortification.

【 授权许可】

Unknown