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By TC Sood
In India, farmers have traditionally used urea mainly because it
is a cheap fertiliser. This helps in foliage formation, and this
leads to insect and pest problems.
For crops such as oil seeds, it is far better to use more balanced
fertilisers with more emphasis on organic manures (such as farmyard
manures) for better seed setting, improved oil content and oil quality.
However deficiencies of secondary nutrients like calcium and sulphur
in oilseeds, pulses and maize, and that of micronutrients in all
these crops affects their productivity adversely. Similarly, soil
acidity in upland areas, and soil alkalinity / salinity in low lying
and water logging prone areas adversely affects growth and yields
of these crops.
There are some critical inputs that are needed by pulses and other
crops as secondary and micronutrients:
Gypsum/pyrites/liming agents
Gypsum, pyrites or rock phosphate are the cheapest sources of important
secondary nutrients. Their application is known to increase both
production and oil content in oilseed crops and yield and quality
of pulses and maize. Gypsum application requires special attention
and thrust because farmers mostly use non-sulphur containing fertilisers
like DAP and mixtures. High transport costs is one of the major
constraints for farmers in using gypsum.
Bacterial agents
Rhizobium culture and phosphate solubilising bacteria (PSB) are
bacteria that enable crops to fix crucial inputs from the soil.
Rhizobium culture is one of the cheapest inputs in increasing production
of pulses and other leguminous crops. The treatment of seed with
this culture helps in fixation of atmospheric nitrogen through its
symbiotic activity. The treatment is particularly beneficial in
areas where groundnut and soybean are a new introduction.
PSB has a capacity to release phosphorus and has been recommended
as one of the low cost inputs for all crops. It helps to reduce
nearly 20 per cent of phosphatic fertiliser input to crops.
But though the treatment of seed with these cultures is highly
recommended, it is necessary to follow certain precautions for usage:
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The culture should be obtained from a reliable source. It
should not be outdated. The date of expiry should be checked
before using the culture. Only cultures with ISI/BIS specifications/standards
should be used. |
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The culture should be well protected from heat and light during
transportation and storage. It should not be stored in places
contaminated with either pesticides or fertilisers. |
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Before using the culture, please ensure that the culture is
meant for that specific crop. |
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The seed treatment with culture should be done either on the
same day or on the previous night. After treatment, the treated
seed should not be exposed to sunlight or high temperatures,
as this kills the bacteria present in the culture. As far as
possible, it should be stored at lower temperatures. Rooms contaminated
with either pesticides or with fertiliser materials should not
be used for storing the culture. |
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It is advisable that the sowing operation is undertaken either
early in the morning or in the evening, so that mortality of
the bacteria is reduced to minimum. |
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If the culture does not possess stickiness, then either rice
starch or jaggery solution should be used to moisten the seed,
so that the culture sticks to the seed coat. |
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Most pesticides are toxic to culture. Thiram is the least
toxic fungicide and dieldrin least toxic insecticide. If these
chemicals are used, culture treatment (slurry-inoculate) should
be given to seed (after pesticide treatment) with double the
normal dose. |
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Slurry-inoculated with Rhizobium culture should never be mixed
with super-phosphate as this is acidic and will kill the bacteria.
In case of PSB, in acidic or alkaline soils, treated seed may
be sown after coating with calcium carbonate or gypsum. |
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The culture use is specifically recommended in areas where
the crop is being grown for the first time. In such areas, culture
application should be repeated for two to three years continuously.
In rice fallow areas the use of culture is very beneficial;
because of anaerobic conditions in rice fields, there is mortality
of native rhizobia. |
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PSB can be mixed with Rhizobium. The bio-fertiliser should
be mixed in equal quantity and applied as mentioned above. The
response to PSB is very good in acidic soils. |
Source: DAC note on National Pulses Development Project (NPDP)
and Integrated Scheme Of Oilseeds, Pulses, Oilpalm & Maize(ISOPOM)
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