20.12.2022 Views

Book of Extended summaries ISDA

Book of Extended summaries ISDA

Book of Extended summaries ISDA

SHOW MORE
SHOW LESS
  • No tags were found...

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges & Opportunities<br />

during 22-24, December 2022 at ICAR-CRIDA, Hyderabad<br />

adoption <strong>of</strong> reduced tillage, crop rotations and residue retention. Several successful case<br />

studies on CA were reported in irrigated systems (Aulakh et al., 2012), but very limited<br />

efforts were made in rainfed production systems. In this background, an attempt was made to<br />

find out the impact <strong>of</strong> CA on system productivity, pr<strong>of</strong>itability, nutrient use efficiency and<br />

GHGs emission in maize-horsegram cropping sequence in rainfed Alfisol.<br />

Methodology<br />

A field experiment was conducted during 2010-2020 at Gunegal Research Farm <strong>of</strong> Central<br />

Research Institute for Dryland Agriculture (CRIDA), Hyderabad. These sandy loam soils are<br />

slightly acidic in reaction, low in soil organic carbon, medium available nutrients (N, P and<br />

K). Among micronutrient Zn was deficient (0.48 mg kg -1 ). Experiment was laid out in split<br />

plot design consisting 2 tillage treatments (conservation= zero tillage and residue retention<br />

(CA) and conventional= 2 ploughing, complete removal <strong>of</strong> residues (CT)) as main plot and<br />

nutrient management (control, NPKSZnB (120-60-40-55-10-0.5 kg N, P 2O 5, K 2O, S, Zn, B<br />

respectively), N, P, K, S, Zn, B omission) as sub plot. Each treatment was replicated thrice.<br />

Chemical fertilizers as N, P, K, S, Zn and B were applied in the form <strong>of</strong> urea (46% N),<br />

diammonium phosphate (DAP) (18% N and 46% P 2O 5), muriate <strong>of</strong> potash (MOP) (60%<br />

K2O), single super phosphate (SSP), Zinc sulfate (21% Zn) and Borax respectively. Hybrid<br />

maize (DHM 117) was grown in rainy season (June-October) following 60x25 cm spacing<br />

and horsegram (CRIDA 18R) was sown just after the harvesting <strong>of</strong> maize.<br />

Results<br />

Pooled data showed that system productivity increased through CA in maize-horsegram<br />

sequence through successful raising <strong>of</strong> Rabi season horsegram crop utilizing <strong>of</strong>f season<br />

rainfall through better soil moisture conservation. Out <strong>of</strong> 11 years (2010-2020), 8 years total<br />

system yield in CA was higher than or at par with CT and in 7 years horsegram crop was<br />

successful. Agronomic efficiency (AE) <strong>of</strong> N, P, K in CA was 22.1, 55.3 and 26.6 kg yield<br />

increase per kg <strong>of</strong> fertilizer nutrients applied compared to 18.8, 40.7, 24.1 kg yield increase<br />

per kg <strong>of</strong> fertilizer nutrients applied respectively in CT due better soil water nutrient<br />

interaction (Aulakh et al.,2012). Higher grain yield <strong>of</strong> horsegram in CA was due to 4.2%<br />

higher soil moisture compared to CT during flowering and grain filling stage <strong>of</strong> horsegram<br />

which helped better grain filling <strong>of</strong> horsegram (Kundu et al., 2013). Significantly higher<br />

gross return (Rs. 37308 ha -1 ), net return (Rs. 20951 ha -1 ) and B:C ratio (2.25) was found in<br />

CA compared to CT. Significantly higher available N (207 kg ha -1 ) and K (180 kg ha -1 ) was<br />

observed in balanced fertilization and N omission treatment respectively. Significantly higher<br />

buildup <strong>of</strong> available K (32 kg ha -1 ) and soil organic carbon sequestration (13.6 Mg ha -1 ) was<br />

observed in CA. Higher SOC was observed in CA (0.64%) compared to CT (0.48%). SOC<br />

decreased with depth irrespective <strong>of</strong> tillage systems. There was no significant difference in<br />

SOC beyond 30 cm soil depth. Higher very labile C was observed in CT (0.38%) compared<br />

Resource conservation and rainfed agriculture<br />

578 | Page

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!