Endophytic bacterial strain GF-55 improves the growth and lodging resistance of maize

Abstract:

[Background] Endophytic bacteria play an important role in crop growth, development and stress tolerance. In this study, an endogenous bacterial strain Pseudomonas moraviensis GF-55 was isolated from maize. [Objective] To analyze the role of GF-55 in the growth and lodging resistance of maize. [Methods] Pot trial was conducted to analyze the role of GF-55 in the growth of maize seedlings and greenhouse trial to study the lodging resistance of maize after GF-55 inoculation. [Results] The pot trial results showed that GF-55 treatment increased the height, dry weight, and fresh weight of maize seedlings by 43.47%, 26.67%, and 82.44%, respectively, compared with the control. Furthermore, it increased the dry weight, fresh weight, length, volume, surface area, and mean diameter of maize root by 231.25%, 96.42%, 141.68%, 46.51%, 37.07%, and 52.38%, respectively. The strain had the indole-3-acetic acid (IAA) production, siderophore relative content, and phosphorus-solubilizing ability of 30.88 μg/mL, 50.20%, and 58.43 mg/L, respectively. The greenhouse trial demonstrated that GF-55 treatment significantly improved the stalk resistance of maize after the silking stage. Specifically, GF-55 treatment increased the stalk puncture, bending, and crushing strength of maize by 15.78%, 55.83%, and 33.71%, respectively, compared with the control. After GF-55 inoculation, the hemicellulose, cellulose, and lignin content in the stalk increased by 10.56%, 2.91%, and 48.01%, respectively. [Conclusion] P. moraviensis GF-55 promoted the growth of maize at the seedling stage and enhanced the lodging resistance after silking stage. It has important application value in maize growth promotion and lodging resistance and provides theoretical support for the development and utilization of this strain.

Key words:maize;endophytic bacteria;growth promoting;lodging resistance