Tillage and nutrient management effects on productivity and nutrient use efficiency of maize

A field experiment was carried out at research farm of ICARIndian Agricultural Research Institute, New Delhi, India during Kharif 2014 on sandy loam soil to study the ‘Tillage and nutrient management effects on productivity and nutrient use efficiency of maize’. The results of study indicated that growth attributes (plant height, dry matter accumulation and leaf area index) and yield attributes (cobs/ha and cob length) were increased significantly with zero tillage (ZT) and SSNM based nutrient management practices over conventional tillage (CT) and traditional nutrient management practices (FFP and control), respectively. In maize, 50% silking and days to maturity were significantly influenced by different tillage practices and these were advanced by about two days in PB and ZT compared to CT. However no significant effect on physiological indices (CGR and RGR) of crop were found in our study. Among the nutrient management practice SSNM gave significantly higher crop growth rates (CGR), cob girth, cob length, grain rows/cob and grains/row over other nutrient management. However, non-significant variation was observed on cob girth, grain rows/cob, grains/row and 1000-grains weight of maize. The ZT and PB increased yield to the tune of 30.0 and 21.5% in grain, 9.5 and 7.6% in stover and 17.8 and 13.2% in biological yields of maize over to CT. But there was only a marginal non-significant difference in 1000-grains weight, harvest index and shelling (%) of maize was noticed under different tillage practices. Amongst the nutrient management treatments, the grain yield in SSNM increased to the tune of 8.2, 31.8 and 75.1% over 100% RDF, FFP and control, respectively. The maximum N, P and K content and their uptake in grain and stover as well as the protein content in grains of maize were recorded in ZT and SSNM fertilized plot over CT and other nutrient management practices. However, the highest water productivity was observed under PB (1.75 kg/ha-m 3 ) and SSNM (1.77 kg/ha-m 3 ). The maximum use efficiency of applied NPK in terms of partial factor productivity, agronomic efficiency and nutrient harvest index was recorded with ZT and SSNM which were followed by PB planting and RDF, respectively. Similarly net returns (42,612 `/ha) and BC ratio (1.76 `/` invested) were observed under ZT flat planting. While among the nutrient management the highest net returns (46,706 `/ha) and BC ratio (1.77 `/` invested) were fetched with SSNM, which was statistically at par with 100 % RDF and significantly higher over FFP and control. However among the tillage treatments, the higher BD and penetration resistance (PR) was recorded in CT and absolute control, while irrespective of treatments the maximum BD and PR were recorded in 30-40 cm soil depth as compare to other soil depth. Beside this, the ZT/PB and SSNM practices registered increase in soil organic carbon by 13-15% and 18-22%; available NPK by12-33 % and 29-81% in different soil layers compared to CT and control plots, respectively. Significantly higher values of soil microbial properties (MBC, FDA hydrolysis, dehydrogenase