Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
Methodology
The field experiment was conducted for two consecutive years (2013-14 and 2014-15) to
evaluate the water use, yield and economic returns from maize under different irrigation
schedules and nitrogen levels at S.V. Agricultural College, wet land farm, Tirupati, Andhra
Pradesh. The experiment was laid out in split-plot design and replicated thrice. The treatments
comprised of four main plots viz., M1 (drip irrigation at 0.7 IW/CPE ratio), M2 (drip irrigation
at 0.8 IW/CPE ratio), M 3 (drip irrigation at 0.9 IW/CPE ratio) and M 4 (weekly check basin
irrigation) and three sub plots viz., N 1 (160 kg N ha -1 ), N 2 (200 kg N ha -1 ) and N 3 (240 kg N
ha -1 ). To schedule the drip irrigation at prescribed IW/CPE ratios the treatments were
maintained to field capacity in the top 0-45 cm depth i.e. only effective root zone depth,
whereas for check basin irrigation the depth of water was 50 cm.
Results
The study revealed that significantly, higher water use efficiency was recorded with irrigation
through drip at 0.9 IW/CPE ratio, but the yield and economics of maize were found to be higher
with weekly check basin method, which were on par to that obtained with drip irrigation at 0.9
IW/CPE ratio (Table 1&2). With regard to nitrogen levels tried, water use efficiency, yield and
economics were found to be superior with the nitrogen dose of 240 kg N ha -1 . This might be
due to the better availability of nutrients under higher soil moisture and at high nitrogen
conditions which might have increased the crop growth and translocation of photosynthates
from source to sink. The benefit from per rupee investment, gross and net returns were higher
with drip irrigation scheduled at 0.9 IW/CPE ratio.
Water use and yield of maize as influenced by drip irrigation schedules and nitrogen
levels
Treatment
M 1 : 0.7 IW/CPE under
drip irrigation
M 2 : 0.8 IW/CPE under
drip irrigation
M 3 : 0.9 IW/CPE under
drip irrigation
Water use efficiency
(kg ha-mm -1 )
Kernel yield (kg ha -1 )
2013-14 2014-15 2013-14 2014-15
Irrigation schedules
11.7 12.2 2582 2717
14.7 14.9 3774 3813
16.4 16.5 4572 4525
M 4 : Weekly check basin 12.9 12.4 4630 4724
Nitrogen levels
N 1 : 160 kg ha -1 11.5 11.8 3177 3289
N 1 : 200 kg ha -1 14.9 14.7 4166 4170
Resilience through land and water management interventions, water management and governance
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