Influence of Salt Stress on Growth of Spermosphere Bacterial Communities in Different Peanut (Arachis hypogaea L.) Cultivars.

Yang Xu,Dunwei Ci,Dai Zhang,Liangxiang Dai,Guanchu Zhang,Feifei Qin,Zhimeng Zhang,Hong Ding

doi:10.3390/ijms21062131

Abstract

Background: Exposure of seeds to high salinity can cause reduced germination and poor seedling establishment. Improving the salt tolerance of peanut (Arachis hypogaea L.) seeds during germination is an important breeding goal of the peanut industry. Bacterial communities in the spermosphere soils may be of special importance to seed germination under salt stress, whereas extant results in oilseed crop peanut are scarce. Methods: Here, bacterial communities colonizing peanut seeds with salt stress were characterized using 16S rRNA gene sequencing. Results: Peanut spermosphere was composed of four dominant genera: Bacillus, Massilia, Pseudarthrobacter, and Sphingomonas. Comparisons of bacterial community structure revealed that the beneficial bacteria (Bacillus), which can produce specific phosphatases to sequentially mineralize organic phosphorus into inorganic phosphorus, occurred in relatively higher abundance in salt-treated spermosphere soils. Further soil enzyme activity assays showed that phosphatase activity increased in salt-treated spermosphere soils, which may be associated with the shift of Bacillus. Conclusion: This study will form the foundation for future improvement of salt tolerance of peanuts at the seed germination stage via modification of the soil microbes.

Highlights

Peanut or groundnut (Arachis hypogaea L.), an important nutritious food and cash crop, is consumed both as oilseed and livestock fodder, forming an important revenue source for farmers [1,2]
To explore the influence of salt stress and different peanut cultivars on the composition of the spermosphere bacterial community, we sequenced the bacterial genomes around various peanut seeds under normal and salt stress conditions
Numerous studies report the presence of seed microorganisms but few have examined the presence of these microbes around plant seeds, especially the oilseed crop peanut [32,33]

Summary

Introduction

Peanut or groundnut (Arachis hypogaea L.), an important nutritious food and cash crop, is consumed both as oilseed and livestock fodder, forming an important revenue source for farmers [1,2]. As a moderately salt-sensitive species, cultivation of peanuts was attempted in low-salinity fields in China to gain more crop production [3,4]. Peanuts growing in these types of fields are impaired by soil salinity throughout their life cycle and their seed germination is the more sensitive stage to salt stress [3,5]. Improving the salt tolerance of peanut (Arachis hypogaea L.) seeds during germination is an important breeding goal of the peanut industry. Bacterial communities in the spermosphere soils may be of special importance to seed germination under salt stress, whereas extant results in oilseed crop peanut are scarce. Conclusion: This study will form the foundation for future improvement of salt tolerance of peanuts at the seed germination stage via modification of the soil microbes

Methods

Results

Conclusion