Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
Results
Tillage practices and mineral nitrogen levels significantly influenced the aggregate stability
indices. Significantly higher mean weight diameter (MWD) of soil aggregates recorded in the
NT (35%) and RT (25%) as compared to the CT in 0-7.5 cm soil depth. Similarly,
significantly higher MWD were recorded under N-125 as compared to the other N levels (Fig
1 A). A similar trend was observed in 7.5-15 and 15-30 cm soil depth with respect to the
MWD. About 70% higher aggregate ratio (AR) was observed in NT, and about 33% higher
AR was observed under RT as compared to the CT. Similarly, nitrogen treatment follows the
order: N-0< N-750.5-0.25>0.25-0.106>1-0.5>2-1>4.75-2
mm>silt+clay at all the soil depths, irrespective of tillage and nitrogen levels. The order of
aggregate and silt+clay associated C content follows: NT>RT>CT, while in case of N levels,
it follows: N-125 >N-100>N-75>N-0. In NT and RT, the C stocks in different macroaggregates
(4.75-2, 2-1, 1-0.5 and 0.5-0.25 mm) increased, while these decreased in microaggregates
(0.25-0.106 and 0.106-0.053 mm).
Effect of different tillage practices and mineral nitrogen levels on A) MWD (mm) and water stable
aggregates (%) in 0-7.5 cm soil depth.
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