施钙对酸性红壤花生根系内生细菌群落结构的影响

花生是我国重要的油料作物,也是嗜钙作物。为了探讨施钙对种植在酸性红壤下的花生根系内生细菌多样性的影响,本研究对不同处理、不同生育期的花生植株根系内生细菌基因组进行16SrRNA基因V3–V4区深度测序,分析种植于酸性红壤中施钙处理和对照下花生植株根系微生物群落结构。结果发现,根系内生菌群落中克雷伯氏菌属(Klebsiella)与肠杆菌属(Enterobacter)在所有样品组中均为优势属且相对丰度较高;花针期不同处理下假单胞菌属(Pseudomonas)与赖氨酸芽孢杆菌属(Lysinibacillus)在施钙组中相对丰度显著高于对照组,而劳尔氏属(Ralstonia)的相对丰度在施钙组中显著降低; Network共发生网络分析显示,施钙组根系内生菌的网络连接相对紧密。综上结果表明,花生根系内生菌群落组成受施钙处理和植株生长发育共同影响,施钙能改变根系内生菌群落结构,提高花生植株应对病原菌侵袭。所得结果为今后通过施钙改良酸性土壤品质进而提高花生植株抗病能力提供了理论参考。

Effects of calcium application on the structural diversity of endophytic bacterial community in peanut roots under acidic red soil cultivation

Peanut is an important economic crop and calcium-loving crop in China.In order to explore the effect of calcium application on the diversity of endophytic bacteria in peanut roots planted in acid red soil,the genomes of endophytic bacteria in peanut roots of different treatments and different growth stages were deeply sequenced by 16SrRNA gene V3–V4 region,and the root microbial community structure of peanut plants planted in acid red soil and control was analyzed.The results showed that Klebsiella and Enterobacter were the dominant genera with high relative abundance in the endophytic bacterial community from all sample groups.The relative abundance of Pseudomonas and Lysinibacillus were significantly higher than that from the control group,while the relative abundance of Ralstonia decreased significantly in the calcium application groups during the pod-pin stage at P≤0.05.The interaction network analysis showed that the connection of root endophytic bacterial in calcium application group was relatively close.We reasonably inferred that the composition of peanut root endophytic bacterial community was affected by calcium application and plant growing development.Calcium application could change the community structure and improve the ability of peanut to cope with external stress.This study may lay a foundation for improving the quality of acid soil and improving the disease resistance of peanut by applying calcium in the future.