Assessment of conservation agriculture and intercropping practices for enhanced productivity and profitability in maize (Zea mays)

Abstract

A field experiment was conducted to study the effect of tillage and intercropping on yield, net returns and weed density in maize (Zea mays L.) at ICAR-Indian Agricultural Research Institute, New Delhi during 2010, 2011 and 2012. The experiment was conducted in split-plot design with three replications. In main plots, tillage systems, viz. conventional tillage (CT), CT + residues at 3 t/ha, zero-tillage (ZT) and ZT+ residues at 3 t/ha were taken. In sub plots, intercropping systems such as sole maize, sole groundnut, maize + groundnut (1:1) and maize + groundnut (1:2) were taken. The results indicated that ZT + residue at 3 t/ha recorded the highest dry matter (DM) accumulation in maize at all the growth stages except 30 DAS followed by CT + residue at 3 t/ha over the years. The yield attributes such as number of gain rows/cob and number of grains/grain row were recorded highest in ZT + residue at 3 t/ha followed by CT + residue at 3 t/ha. The residue retention at 3 t/ha in ZT enhanced 25.3-28.9% grain yield in maize compared to CT over the years. ZT + residue at 3 t/ha recorded the highest net returns (49.8 × 103 /ha) and B:C ratios (1.7) in maize. In 2010, weed population of broad-leaved weed (BLWs), narrow-leaved weed (NLWs) and total was recorded highest in ZT + residue at 3 t/ha. However, the population of BLWs and total increased in CT compared to ZT at the end of the study period. The intercropped system, viz. maize + groundnut in 1:1 and 1:2 recorded the lowest DM accumulation than the sole maize over the years. The number of grain rows/cob and number of grains/ grain row were recorded highest in sole maize compared to intercropped maize. However, higher grain yield and net returns was found in maize + groundnut in 1:1 and 1:2 than sole maize. The intercropped maize + groundnut in 1:1 and 1:2 recorded the lowest population of BLWs, NLWs and total during the years.