Recent research published in the journal ‘Rice’ has unveiled promising findings regarding the role of native actinobacterial strains in enhancing the growth of rice plants. Led by Dhivya P. Thenappan from the Systems Plant Physiology at Texas A&M AgriLife Research and Extension Center, the study focused on strains of Streptomyces isolated from both the rhizosphere and endosphere of rice plants in India.
The research highlights the plant growth-promoting (PGP) capabilities of these actinobacterial strains, which were shown to positively influence various growth metrics in rice. The team conducted extensive screenings, revealing that all tested isolates produced indole-3-acetic acid, a key plant hormone, and siderophores, which help in nutrient uptake. Notably, strain FT1 was identified as the only one capable of producing hydrogen cyanide, a compound that can deter pests.
In pot culture experiments, the results were striking. Rice seeds inoculated with the FB2 and FTSA2 strains exhibited increases in shoot dry mass by 7% and 34%, respectively, and total biomass by 8% and 30%. Furthermore, the strains contributed to enhanced nitrogen levels in the leaves, which is crucial for plant health and productivity. “These actinobacterial strains enhance both aboveground and belowground crop characteristics,” Thenappan noted, emphasizing their potential benefits for farmers.
The study also utilized qRT-PCR analysis to measure the expression of genes associated with phytohormone pathways, revealing that the actinobacterial treatments led to distinct changes in gene expression related to auxins, gibberellins, and cytokinins. This molecular insight provides a deeper understanding of how these beneficial microbes interact with plants at the genetic level.
The implications of this research extend beyond academic interest; they present significant commercial opportunities. As the agricultural sector increasingly seeks sustainable practices, these native actinobacterial strains could be developed into bioinoculants. Such products would not only enhance crop yields but also contribute to integrated nutrient management practices, reducing the reliance on chemical fertilizers.
Given the growing demand for sustainable agriculture solutions, the findings from this study could pave the way for new products that support healthier crops and more resilient farming systems. The potential for commercial bioinoculants derived from these Streptomyces strains could be a game-changer for farmers looking to improve productivity while minimizing environmental impacts.
