Abstract
Mycorrhizae contribute significantly for plant growth and development,
providing nutrients such as phosphate and nitrogen, while also enhancing
stress tolerance and resistance against phytopathogens. Plant symbiotic
mycorrhizal networks harbour bacterial communities that aid mycorrhizal
functions and augment plant nutrition and development. Various bacterial
associations of mycorrhiza bring forth advantageous traits to
mycorrhizal symbiosis and host colonization, which involves a wide range
of signalling and regulatory molecules. These regulatory molecules play
an important role in adapting and responding to new microenvironments
with different hosts through the production of metabolites and
expression of favourable genes. Small molecular components such as
non-coding RNA (miRNA and sRNA) are also involved in the regulation and
adaptation to these microenvironments. Regulatory pathways involving
protein kinases play an important role in the tripartite association of
bacteria and mycorrhiza with plants, and the subsequent promotion of
symbiotic interactions. This mini-review highlights potential bacterial
regulatory candidates which can influence mycorrhiza-plant interactions
to significantly benefit plant growth and development. An understanding
of these bacterial regulatory mechanisms may suggest new strategies for
knowledge-based application in crop productivity improvement programs.