Vol. 7, Issue 6 (2018)

Author(s):
M Ramanjineyulu, M Srinivasa Reddy, PV Ramesh Babu and P Kavitha

Abstract:
Reduced atmospheric nutrient deposition, in conjunction with higher grain sale prices and steadily increasing yields of maize (Zea mays L.) has many growers considering an increase in secondary and micronutrient applications. Limited information exists quantifying requirements of S, Mg, Ca, Zn, Mn, Cu, Fe, and B across a wide yield range for modern maize production systems. The objective of this study was to evaluate macro- and micronutrient accumulation and partitioning in maize. Supplemental fertility modestly increased biomass and yield (2%), but did not alter nutrient partitioning or harvest index. Nutrients with high harvest index (i.e., percentage of total nutrient accumulation partitioned to grain) values included P (83%), N (71%), Cu (64%), and S (60%), which may serve as a limitation to high yield. Seasonal patterns of nutrient accumulation suggested that K and Fe were acquired primarily during late vegetative growth while the uptake of N, P, Ca, Mg, S, Zn, Mn, B, and Cu were more equally distributed between vegetative and seed-filling growth phases. These results document the rate and duration of macro- and micronutrient accumulation in maize, and highlight the importance of adequate nutrient availability during key crop growth periods.