Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
EA3000). The glomalin content of aggregate samples were extracted using 50 mM sodium
tricitrate, pH 8.0, 121OC for 1 hr (Wright and Upadhyay, 1999). The total polysaccharides
were analyzed by phenol sulphuric acid method by Lowe (1994). The total carbohydrate was
analyzed by phenol sulphuric acid methodby Dubois et al, (1956). Total polyphenols of POM
fractions were determined by Prussian Blue spectrophotometric method.
Results
The effect of different treatments on mean weight diameter (MWD), geometric mean
diameter (GMD) and water stable macro-aggregates (WSMA) in the rice-rice cropping
system of BHNS and PTMBare given in the table. The study showed that the C associated
with 2.00-0.25mm aggregates varied from 3.53 g kg -1 in 50 % NPK to 10.11 g kg -1 in plots
treated with 100% NPK+FYM in soils of BHNS and from 11.7 g kg -1 in control to 23.1 g kg
-1
in plots treated with 100%NPK+FYM in that of PTMB. In the 0.25-0.053 mm fraction,
inBHNS,100% NPK+FYM (11.1 g kg -1 ) had higher C content, whereas in the effect of
different treatments on biochemical stability of aggregates showed that addition of 100%
NPK+FYM increased glomalin content (3.43 mg g -1 ) significantly in macro aggregates and
also in micro-aggregates (3.25 mg g -1 ) in BNHS. Similar trend was observed in both the
macro and micro-aggregates of PTMB. The combined application of FYM with 100% NPK
significantly increased polysaccharide content in macro-aggregates (i.e. 6.09 g kg -1 ) and
micro-aggregates (5.6 times compared to control) indicating that addition of FYM increases
biochemical stability of aggregates at BHNS. However, in the soils of PTMB, the application
of 150% NPK increased polysaccharide content in the macro-aggregate fractions and the
combined application of FYM with 100% NPK (i.e. 12.8 g kg -1 ) in micro-aggregates
compared to other treatments. The biochemical stability of micro-aggregates with application
of fertilizers only, was significantly lower in general. The control soils had the lowest
polysaccharide content and hence biochemical stability. The addition of either FYM or lime
with 100% NPK significantly increased carbohydrate content in the POM fractions obtained
from aggregates at both the sites. Addition of FYM with 100% NPK significantly increased
polyphenol content by 1.73 times and by 1.65 times in the POM fractions at BHNS and
PTMB respectively.
Long-term effect of manuring and fertilization on mean weight diameter (MWD),
geometric mean diameter (GMD) and water stable macro aggregate (WSMA>0.25mm) at
0-15 and 15-30 cm soil under rice-rice cropping system in Bhubaneswar and Pattambi
Treatments
Bhubaneswar
MWD (mm) GMD (mm) WSMA >.25mm
0-15 cm 15-30 cm 0-15 cm 15-30 cm 0-15 cm 15-30 cm
50% NPK 0.88bc 0.92c 1.001e§ 1.003c 0.69c 0.74d
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soil-microorganisms-plant interactions