Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges & Opportunities
during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
increasing amounts of crop residue maintained on the surface (Sharma et al., 1990). Greater
infiltration, less evaporation, and effective weed control contributed to the higher soil water
contents with conservation tillage.
Methodology
To achieve the objective, an experiment with surface application of 4 levels of sorghum residues
@ 0, 2, 4, 6 t ha -1 in combination with N (30 kg N ha -1 for cowpea and 60 kg N ha -1 for Sorghum
through urea) and uniform dose of 30 kg P2O5 ha -1 (through super phosphate) with minimum
tillage, was initiated during 2005 at ICAR-CRIDA Research farm Hayathnagar, Hyderabad. The
cropping system adopted in this study was Sorghum-Cowpea with yearly rotation. The soil
moisture was measured using Soil Moisture Meter (Micro Gopher, Nu-Tech). Soil moisture were
recorded in treatment plots at 8 depths viz., 0-10 cm, 10-20cm, 20-30 cm 30-40 cm, 40-50cm,
50-60 cm, 60-70 cm, 70-80cm. Soil moisture at field capacity (1/3 bars) and permanent wilting
point (15 bars) was measured using pressure plate apparatus. The difference in soil moisture at
field capacity and permanent wilting point was recorded as soil available moisture.
Results
Soil Moisture: It was observed that, during the crop season (June-September), on an average, the
soil moisture at 0-10 cm depth varied from 11.2 to 16.6% across the treatments. The increase in
soil moisture at 0-10 cm depth was 18%, 25%, 49%, with 2, 4 and 6 t ha -1 residue treatments
respectively over control. The soil moisture contents increased with increase in level of
application of residues in all the depths studied (0-80cm). The results pertaining to the effect of
residue application on soil moisture % (January- April) are given hereunder (Fig.1). It was
observed that the residue applied @ 6t ha -1 (T4) recorded higher soil moisture content at all the
depths studied. At 0-10 cm depth, application of residues at 6t ha -1 resulted in highest moisture
storage in the soil compared to other treatments after the harvest of the crop. The treatments @ 2,
4 and 6 t ha -1 , on an average recorded 25%, 34% and 57% higher soil moisture contents
respectively over control. It was observed that at 10-20 cm soil depth, on an average, soil
moisture was lower compared to surface soil. At this depth, the residue treated plots stored 27%,
51% and 78% higher moisture compared to no residue treatment. On an average, at 20-30 cm
depth also, residues influenced soil moisture storage. The treatments viz T2, T3 and T4
maintained 47%, 58% and 80% higher soil moisture compared to control. During the first three
weeks and between 11-13 th meteorological weeks, there was no receipt of rainfall. Despite non
receipt of rainfall, T4 treatment maintained higher soil moisture storage followed by T3 and T2
treatments. The control treatment (no residue) stored the least amount of soil moisture.
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