关键词: 小麦, 药隔期, 倒春寒, 根际, 细菌群落

Abstract: Crop rhizosphere microorganisms is crucial for their growth, development and adaptability to stress. A field pot experiment was conducted using Yannong19(YN) with strong resistance to late spring coldness and Xinmai26(XM) with weak resistance to late spring coldness. 4℃(T1) and −4℃(T2) low temperature stress treatment were carried out in intelligent ultra-low temperature incubator during the anther differentiation period of young wheat spike differentiation, and 15℃ was used as control group(CK). High-throughput sequencing technology was used to determine the bacterial community in wheat rhizosphere soil, and to analyze the effects of late spring coldness during the anther differentiation period on the diversity and community structures of wheat rhizosphere bacteria. The results showed that: (1) late spring coldness decreased the ACE index of bacteria in rhizosphere soil of the two wheat varieties, and the ACE index of the variety XM with weak resistance to late spring coldness was significantly affected (P<0.05). (2) The bacterial community in rhizosphere soil of the two wheat varieties were mainly composed of 33 phyla and 819 genera, including Proteobacteria(53.20%−57.55%), Actinobacteria (13.34%−21.69%), Bacteroidetes(10.56%−12.37%), Gemmatimonadetes(6.17%−9.19%). The relative abundance of various bacterial phyla showed differences among different degrees of late spring coldness treatment. Late spring coldness increased the relative abundance of Actinobacte by 9.79%−19.11% in YN, and decreased by 26.43% −38.47% in XM. (3) Function prediction analysis indicated that that late spring coldness during the anther differentiation period increased the gene abundance of membrane transport, amino acid metabolism, carbohydrate metabolism, replication and repair in YN rhizosphere soil, and decreased their gene abundances in XM rhizosphere soil. In conclusion, late spring coldness during the anther differentiation period reduced the richness of the bacterial community in the wheat rhizosphere soil, changed the bacterial community structure, and affected the membrane transport, amino acid metabolism, carbohydrate metabolism, and replication and repair functions of the bacterial community.

Key words: Wheat, Anther differentiation period, Late spring coldness, Rhizosphere, Bacterial community