Effect of Frankia and Micromonospora on growth and health improvement in Casuarina clones

ABSTRACT

Casuarinas have been used for paper and pulp, and many Casuarina clonal plantations were made in India. Two actinobacteria, Frankia and Micromonospora, colonize in root nodules of Casuarinas and improve the growth of their host plants as a symbiotic nitrogen fixer and a biocontrol agent against Ralstonia solanacerum, a wilt desease bacteria damaging young clonal plantations, respectively. In the present study, antimicrobial activity of Micromonospora against Ralstonia solanacearum was examined. Then, effects of Frankia and Micromonospora on the growth and nitrogen content in Casuarina hybrid clones were examined in the greenhouse. The biocontrol activity of Micromonospora against a bacterial wilt was also evaluated in Casuarina plantations. The results showed that Micromonospora suppressed the growth of R. solanacearum under laboratory conditions and that the growth of Casuarina clones was improved by the addition of cultured Frankia and/or Micromonospora. The bacterial wilt in Casuarina clonal plantations might be suppressed due to the biocontrol activity of Micromonospora.

KEYWORDS:

• Casuarinas
• Frankia
• Micromonospora
• bacterial wilt
• Ralstonia solanacearum

Acknowledgments

The authors thank the Indian Council of Forestry Research and Education, India, for financial support and facilities in a form of research project.

Author contributions

A. Karthikeyan conceived the idea of research and conducted the experiments with all statistical analyses. K. Kanchanadevi assisted in collecting data, maintenance of plants and microbes used in this research. A. Nicodemus provided the Casuarina plants for this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was a part of a research project entitled ‘Bioformulations of Micromonospora for bio control and biofertilization activity in Casuarinas’ funded by the Indian Council of Forestry Research and Education, Government of India vide project No. [IFGTB/RP-173/2018].