Agriculture Reference
In-Depth Information
So, in such cases, “soil inoculation” method should be adopted wherein a large
population of a bacterial strain can be introduced directly into the soil. For soil
inoculation, in general, granular inoculant is placed into the furrow under or
alongside the seed. This enhances the chance for the inoculated strain to be in
contact with plant roots. Alternatively, four packets of microphos are mixed with
20 kg of dried and powdered farmyard manure (FYM) and then broadcasted in one
acre of main field just before transplanting. This method allows a rapid and greater
colonization of P-solubilizing organisms per unit area. In addition, the direct
contact of inocula with chemically treated seeds is minimized. This method also
offers advantages like (i) it is quick compared to seed inoculation technique which
requires mixing of seeds with inoculants, (ii) inoculants can withstand low-moisture
conditions better than carrier-based inoculants and (iii) it is less expensive com-
pared to other inoculation methods. Thus, in accordance with these considerations,
two approaches can be applied for microphos applications: (i) the monoculture
approach [MCA] where P-solubilizing microorganisms can be used alone and
(ii) the co-culture or multiple culture approach [CCA], where microphos prepared
from two or more identical or different microbial strains can be mixed together and
then applied under natural field/pot house conditions. The bacterial inoculants,
however, should not be mixed with insecticide, fungicide, herbicide and fertilizers.
When seeds are treated with fungicides, the seeds should be treated first with
pesticides and then with microphos.
1.6 Conclusion
In high-input agricultural practices, the deficiency of soil P is circumvented mainly
through the use of chemical phosphatic fertilizers, the excessive and continued use
of which results in loss of soil fertility and, hence, the crop productivity. Microphos
in this context might play a pivotal and practicable role in enhancing the soil P pool
without adversely disturbing the soil microflora and the processes mediated by
them. Since majority of microbial inoculants developed so far are used for enhanc-
ing legume, cereal and some vegetable production, there is an increasing demand
from fruit and vegetable production sector, where use of chemical fertilizers is
either not allowed or is restricted for human health reasons. In this regard, the
development of microphos could serve a viable option for such crops, and using
microphos, some success has been achieved over in different production systems.
The challenge, however, is to find some novel phosphate-solubilizing microorgan-
ism expressing multiple growth-promoting activities that could be applied under
diverse agroecosystems. Moreover, there is a need to develop some simple tech-
niques for mass production of microphos and its delivery systems so that the use of
microphos could be popularized and increased across different regions in a sustain-
able manner. The commercialization of microphos is, however, a challenging task
which requires full-scale, cost-effective manufacturing, packaging and quality
control systems. Furthermore, the large-scale field trials for microphos are needed
