Isolation, characterization and screening of bacterial endophytes from Zea mays L. var. rugosa (sweet corn) Sugar King variety with biotechnological potential in agriculture

DANILEE JOSHUA S. HALABA, JONATHAN S. MOLINOS, JP P. SUPERFICIAL and ANDREA LUCYLE BELA-ONG

Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology, Philippines

Abstract

This study aimed to determine the plant growth promoting activities exhibited by bacterial endophytes isolated from the roots of Zea mays L. var. rugosa (sweet corn) Sugar King. A total of eight different bacterial strains were isolated and characterized through Gram staining and screened for a positive reaction for nitrogen fixation, ammonia production and zinc solubilization through the use of Jensen’s media, peptone water with Nessler’s reagent, and zinc incorporated media, respectively. Results showed that Gram-negative bacteria were the dominant group. Colony characterization showed that circular forms comprised the majority. Similarly, the colonies with entire forms and either pulvinate or flat elevation were recurrent throughout the isolates. Cell characterization revealed that all isolates were rod in shape. The plant growth promoting screenings revealed that all isolates were plant growth promoters. All were found to be positive for ammonia production and zinc solubilization; however, none were found to be positive for nitrogen fixation.

Keywords: endophytes, nitrogen fixation, ammonia production, zinc solubilization, Zea mays L. var. rugosa