Quality Control
RBDC, Imphal
has a lab for testing the quality of the products. As a
voluntary service to the farmers and channelising agencies, RBDC
undertakes the quality analysis of all types of biofertilizers.
This service is free for all. As the quality parameters are
highly technical, it is not to be done at farmers end. Details
of Quality control analysis since inception at RBDC is as
follows :
| Year |
Sample Tested |
Sub-Standard |
| 1995-96 |
84 |
6 |
| 1996-97 |
67 |
- |
| 1997-98 |
49 |
- |
| 1998-99 |
55 |
- |
| 1999-00 |
42 |
- |
| 2000-01 |
26 |
- |
| 2001-02 |
30 |
4 |
| 2002-03 |
69 |
16 |
How to send
the sample
The sample
should be sent in the forms of packet/parcel for each batch to
be tested (preferably in two packets) for quality analysis. The
address of the sender should be mentioned clearly in case the
result is to be delivered by post. The result/report will be
provided within 15-30 days time.
Precaution
As
bioferlilizers are live product, they should be handled
carefully and shall not be exposed to heat and direct sunlight.
While sending for testing, the packet/parcel should be properly
sealed and intact.
Standard
values of biofertilizes
| Parameters |
Rhizobium |
Azotobacter |
Azospirillium |
PSM |
| Total
Viable count within 15 days of manufacture |
>1X108 |
>
1X107 |
>1X108 |
>1X108 |
| Contamination |
Nil |
Nil |
Nil |
Nil |
| Total
Viable count within 15 days before Expiry |
>
1X107 |
>
1X106 |
>
1X107 |
>
1X107 |
| PH
Value |
6.0-7.5 |
6.0-7.5 |
6.0-7.5 |
6.0-7.5 |
| Strain
Efficiency |
Capable
of producing good modulation. dry weight of treated
plants should be 50% more over control |
Capable
of fixing 10mg of N/gm of sucrose consumed |
Capable
of fixing 10mg of N/gm of malate used |
Capable
of developing a P-solubilization zone of > 10mm |
Testing
quality of biofertilizers at user’s end
To obtain good
results, the biofertilizer packet must contain all the traits in
general and appropriate microbial load of appropriate strain in
particular as mentioned earlier, but as the quality requirements
are very specific and require the services of a full fledged
quality control laboratory, it is very difficult to ascertain it
as user’s point. However, for personal satisfaction one can
use following method to evaluate the efficacy of the product.
But remember this is only a qualitatively indicator method and
its correctness varies widely depending upon handling and
materials.
Steps to follow :
| 1 |
Take
4-5 kgs of good garden soil and sterilize it in a
pressure cooker for 30-40 minutes. After cooling fill
this soil in 6 small pots. |
| 2 |
Select
the right combination of seed and biofertilizer. |
| 3 |
Treat
half of the seeds with appropriate biofertilizer using
standard seed treatment method. |
| 4 |
3
pots should be sown with treated seeds while 3 pots be
sown with untreated seeds to serve as control. |
| 5 |
Keep
the pots in protected open space and ensure daily
watering. |
| 6 |
Observe
after 30-40 days. |
Observation :
| RHIZOBIUM |
In
case of leguminous seeds treated with right type of
Rhizobium biofertilizer, the treated plants will show
adequate nodulation on roots with higher plant weight
compared to untreated control, which will show either no
or very few small nodules. |
AZOTOBACTER/
AZOSPIRILLUM |
In
case of non legume, treat appropriate test host seeds
(such as maize) with Azotobacter or Azospirillium
biofertilizer, the treated plant will be healthier,
having green colour and higher plant weight compared to
untreated control which will show lesser plant weight
and pale green plant colour. |
Criteria for
geting good response of
biofertilizers
| 1 |
Product must contain good effective strain in appropriate population should be free from contaminating
microorganisams. |
| 2 |
Select right combination of biofertilizers and use before expiry. |
| 3 |
Use appropriate method of application and apply at appropriate time. |
| 4 |
For seed treatment use adequate adhesive for better results. |
| 5 |
For
problematic soils use corrective methods like lime or gypsum pelleting of seeds or correction of soil pH by use of lime. |
| 6 |
Ensure the supply of phosphorus and other nutrients. |
Reasons for poor
response
|
1 |
|
On accounts of quality of product. |
| |
a) |
Use of ineffective strain. |
| |
b) |
Insufficient population of
microorganisams |
| |
c) |
High level of contaminants |
|
2 |
|
On account of inadequate
storage facilities |
| |
a) |
May have been exposed to high temperature |
| |
b) |
May have been stored in hostile conditions. |
|
3 |
|
On account of usage |
| |
a) |
Not used by recommended method in appropriate
doses |
| |
b) |
Poor quality adhesive |
| |
c) |
Used with strong doses of plant protection
chemicals |
|
4 |
|
On account of
soil and environment |
| |
a) |
High soil temperature or low soil moisture |
| |
b) |
Acidity or alkalinity in soil |
| |
c) |
Poor availability of phosphorous and molybdenum |
| |
d) |
Presence of high native population or presence of bacteriophages |
|
