Enhancement of Zea mays (L.) growth performance using indole acetic acid producing endophyte Mixta theicola isolated from Solenostemma argel (Hayne)

• Published in: South African journal of botany 2020-11, Vol.134, p.64-71
• Main Authors: Hagaggi, Noura Sh.A., Mohamed, Amal A.A.
• Format: Article
• Language: English
• Subjects: Biochemical traits; Indole acetic acid; Mixta theicola; Solenostemma argel; Zea mays
• ISSN: 0254-6299; 1727-9321
• DOI: 10.1016/j.sajb.2020.02.034

•Mixta theicola strain SAR (accession no. MN414603) was isolated from the roots of Solenostema argel plant.•Strain SAR was characterized by its superior ability to produce the phytohormone IAA.•Inoculation of Zea mays grains with strain SAR significantly affected seed germination, root elongation, seed vigor index as well as fresh and dry biomasses.•The biochemical traits, e.g., chlorophyll, total carbohydrates, anthocyanins, total phenolics and flavonoids were up-regulated in SAR-inoculated seedlings.•The total antioxidant capacity was altered in response to SAR inoculation.•Strain SAR can be used as biofertilizer in agriculture. Indole acetic acid (IAA) is one of the most important phytohormones as it is incorporated in various growth regulation processes in plants. In the present study, Solenostemma argel (Hayne) plant was investigated for the first time for potential isolation of associated plant growth-promoting endophytic bacteria, i.e, IAA producing bacteria. Mixta theicola strain SAR was isolated from the roots of S. argel. The isolated strain was used for the inoculation of the grains of Zea mays (L.). The germinated seedlings were transplanted in pots and grown at 28 °C for 15 days. Then, the growth performance of seedlings was measured. Inoculation resulted in a significant enhancement of seed germination, root elongation and seedling vigor index. In addition, both fresh and dry biomasses of the seedlings of Z. mays were significantly increased (P < 0.05). Biochemical constituents, e.g., chlorophylls, carbohydrates, proteins, anthocyanins, total phenolics and total flavonoids were increased in the inoculated seedlings. Total antioxidant capacity (TAC) was also enhanced in the inoculated seedlings. Therefore, the study suggested the use of strain SAR for seed coating in agricultural application for enhancement of crop growth performance.