Agriculture Reference
In-Depth Information
Actinoplanes
ME3, and
Micromonospora
MM18 has been found to promote the
growth of
Discaria trinervis
in symbiosis with
Frankia
; however, no plant-growth-
promoting effect was observed when rhizoactinomycetes were applied alone to the
plant (Solans
2007
). In a similar study, Hamdali et al. (
2010
) isolated a population
of PS actinomycetes spp. from Moroccan phosphate mines and tested their growth-
promoting efficacy using wheat as a test plant. The most active RP-solubilizing
strains had the highest stimulatory effect on the production of plant biomass. Of the
various isolated actinomycetes strains, strain BH7 of
Streptomyces griseus
stimu-
lated aerial growth of the plant by 70 % in test tubes and more than 30 % in RP soil
compared to the non-inoculated control plants. In another study, the actinomycetes
showed P solubilization activity (1,916 mg l
1
) and produced phytase
(0.68 U ml
1
), chitinase (6.2 U ml
1
), IAA (136.5 mg l
1
), and siderophore
(47.4 mg l
1
). Furthermore, inoculation of
Streptomyces
mhcr0816 and
mhce0811 with
Triticum aestivum
(wheat) significantly improved plant growth,
biomass (33 %), and mineral (Fe, Mn, P) content in non-axenic conditions (Jog
et al.
2014
).
6.4 Conclusion
In order to reduce the environmental and economic stress due to massive use of
synthetic fertilizers and to achieve food security goals, the use of actinomycete as
biofertilizers in intensive agriculture practices appears to be a sound, inexpensive,
and eco-friendly option. Even though the physiological functions and symbiotic
roles of actinomycetes have been revealed under in vitro condition, the role of
actinomycetes in sustainable crop production is not adequately explored. Consid-
ering the importance of actinomycetes in plant growth promotion via disease
suppression and some other mechanisms, there is urgent need to popularize and
maximize the use of actinomycetes in crop production in order to reduce depen-
dence on chemical fertilizers and hence to preserve soil fertility without damaging
the soil dwellers.
References
Abdulla H (2009) Bioweathering and biotransformation of granitic rock minerals by actinomy-
cetes. Microb Ecol 58:753-761
Ahmad E, Khan MS, Zaidi A (2013) ACC deaminase producing Pseudomonas putida strain PSE3
and Rhizobium leguminosarum strain RP2 in synergism improves growth, nodulation and
yield of pea grown in alluvial soils. Symbiosis 61:93-104
Amoroso MJ, Benimeli CS, Cuozzo SA (2013) Actinobacteria: application in bioremediation and
production of industrial enzymes. CRC, Boca Raton, FL, p 296
Ara´ jo JM, Silva AC, Azevedo JL (2000) Isolation of endophytic actinomycetes from roots and
leaves of maize (
Zea may
L.). Braz Arch Biol Technol 43:447-451
