physicochemical

Research Note
J.Res. ANGRAU 39(1&2)64-68, 2011
STUDIES ON EFFECT OF ORGANIC AGRICULTURAL INPUTS ON SOIL
NUTRIENT AVAILABILITY AND PLANT DEVELOPMENT IN GREEN GRAM
(Phaseolus aureus Wilczek)
CH ANURADHA, RAMESH THATIKUNTA, G SWARAJYALAKSHMI and PRABHU PRASADINI
Dept of Bioresources Management and Plant Physiology
College of Agriculture, Acharya NG Ranga Agricultural University, Rajendranagar 500030
In the present investigation, the problem of low
productivity in green gram has been sought to be
improved by the use of organic agricultural inputs
certified as “agri inputs” (www.Prathista.com). These
agri inputs, which have been recently introduced into
market, show high bio availability and readily
absorbable nature as compared to inorganic
fertilizers. Hence, the present investigation has been
taken up, to evaluate the effect of agri inputs on soil
nutrient availability, crop development and
productivity.
Pot culture study was taken up in the College
of Agriculture, Rajendranagar, during kharif 2009.
Organic agricultural inputs viz., Bio-PhosG and Bio-
PotashG granules @ 75 Kg ha -1 along with Bio-ZincG
@ 12.5 kg ha -1 + FYM @ 5 t ha -1 were added to pots
as given in table 1. Nitrogen basal dose was applied
as urea @ 20 kg ha -1 . Treatments with twelve pots
each were maintained, with three replications. WGG-
37 greengram variety was selected for the study.
Effect of organic inputs was quantified in terms of
OC (Walkley and Black, 1934) SPAD chlorophyll
content and number of effective nodules. N, P, K
and Zn were estimated in soil following standard
procedures. Data recorded was analyzed in two
factorial randomized block design. Seed yield and
its regression on soil nutrient content, was calculated
following Gomez and Gomez (1984).
Soil organic carbon estimated after harvest of
crop increased significantly (Table 1). The highest
mean organic carbon content of 1.44% was recorded
in treatment (20N-40P-20K) where K was applied
through Bio-Potash followed by the treatment where
P, K and Zn were applied through organic inputs which
recorded 1.33%. Inorganic fertilizer application
resulted in lower value (1.00%) and was on par with
control (1.06%). The mean organic carbon content
increased from 30 to 45 days and then decreased at
60 th day after sowing. In any case the soil organic
carbon content can be rated as high as per soil test
data values of >0.75% (Prasad Rao and Bhupal Raj,
2001). M/S Prathista products Bio-PhosG, Bio-
PotashG, Bio-ZincG themselves contain 3.24, 3.98
and 4.42% OC respectively improved soil OC.
Improvement in OC content was recorded also upon
application of urban garbage compost (Poornesh et
al., 2004).
Application of inorganic fertilizers alone and
along with organic agricultural inputs improved the
soil N. The interaction between treatments and DAS
was also found significant (Table 1). The highest soil
available nitrogen (179.17 kg ha -1 ) was recorded where
20N-40P-20K were applied through inorganic
fertilizers, followed by the treatment, where K was
substituted by Bio-PotashG (151.43 kg ha -1 ) and the
lowest (82.22 kg ha -1 ) was recorded in control. With
increase in days after sowing from 30 to 60 there
was decrease in soil available nitrogen from 152.09
to137.27 kg ha -1 . Use of Bio-PhosG improved the
soil N when used in combination, as Bio-PhosG
contains 3.5 to 4% ammonical N readily available to
crops and hence most effective than inorganic salts
applied alone (Prathista.com). The N value reported
were in the low range for soils of