Deep-rooted gains

-- FIELD experience of farmers and extensive research conducted in the farms of
Tamil Nadu-based Sakthi Soyas Ltd.,
have established the profitability of
soyabean intercropping with sugar cane.
During the last 3 years, soyabean intercropping with the major cultivated
crops was tried and its intercropping
with sugar cane was found to be the best
(Kisan World, Vol 22, No 6).

Because growing sugar cane involves
a long gestation period of about 12
months, small and marginal farmers
resort to intercropping of short-
duration crops like vegetables, pulses
and groundnuts to sustain
them through this time span.

With a minimum spacing of 80 to 90 cm that
is required to be left
between rows of sugar
cane plants, adequate area
is available for easy intercropping of soyabean.

An excellent compatibility for co-existence of
these 2 crops is found on
account of mutually accommodating physical structures of
the plants. While the sugar cang plant
has erect leaves, soyabean has broad
leaves of horizontal spread that makes
utilisation of solar radiation full and effective.

Further, there is found to be no
competition between sugar cane and
soyabean plants for essential resources,
as water and nutrient requirements for soyab6an are low.

Moreover, researchers found that
this intercropping considerably reduces
the dependence of sugar cane on chemical fertilisers. This is due to bio-fixation of nitrogen by the root
nodules of soyabean. As
only one-third of nitrogen
thus fixed is used by soyabean, the rest is left in the
soil for sugar cane.

Heavy soyabean leaf
shedding is regarded as
another -benefit of this
intercropping. Occurring, Rm at a rate of about 3 tonnes
of soyabean leaves per
hectare, it adds to the
humus content of the soil
making it more fertile.
Besides, it is found to create a leaf-covering of the
area between the cane rows,
thereby preventing excessive
evaporation of moisture and
nutrients. It is found to
smother weed growth as well.

Researchers found that
soya roots possess excellent
penetrating power which
aids in breaking clay-
colloids in heavy soils, thus
providing better porosity and
aeration.

In light sandy soils, these
roots aid the binding of soil particles,
helping in retention of moisture and
nutrients in the top layer.

Considering that sucking and boring pests cause tremendous damage to
cane growth, soya leaves which are softer and more succulent than sugar cane's
are found to provide a preferable feast
for these pests. Researchers have confirmed that soyabean proves to be a
good "trap-crop" for cane pests which
considerably reduces their attack on
sugar cane plants.

All findings indicate that soya
intercropping enhances sugar caneyield
by a minimum of 7 to 10 per cent as
compared to sole cropping of sugar
cane. In addition, soyabean crop residue
can provide cattle fodder to sugar cane
farmers who face immense problem in
raising enough cattle fodder till cane-harvest.

In view of the indirect benefits that
soyabean intercropping with sugar cane
provid4, agriculturists are convinced
that thi pattern of intercropping with
sugar cane is "agronomically advanta
geous &Ad economically more remunerative to, the needy farmers."