DefinePK

Abstract

Nitrogen (N) and sulfur (S) are important crop nutrients limiting the crop growth and yield. In order to study N and S effect on growth, dry mater partitioning and grain yield of maize, a field experiment was conducted at the New Developmental Research Farm of Khyber Pakhtunkhwa (KPK), The University of Agriculture, Peshawar during summer 2011, which was designed in randomized complete block design (RCBD) replicated thrice. Growth, dry matter partitioning, yield & yield components, and harvest index responded positively to N and S fertilization, but the magnitude of response varied with level of N and S application. Days to tasseling, silking and physiological maturity delayed, plant height and mean single leaf area increased with increase in N and S levels. Similarly, dry matter partitioning in stem, leaf, ear, and grains was increased with an increase in N and S levels and decreased in the control plots. The heaviest thousand grains weight was obtained when both N and S were applied at the highest rates. The highest grain yield viz., 3122 kg ha-1 was obtained in the plots where N was applied @ 160 kg ha-1, while minimum grain yield i.e. 2039 kg ha-1 was obtained in control plots. Grain yield increased to maximum (2882 kg ha-1) when S was applied @ 40 kg ha-1, and the lowest grain yield (2458 kg ha-1) was recorded in control plots. The harvest index ranked first when both N (27.8%) and S (27.7%) were applied at the highest rates of 160 kg N and 40 kg S ha-1. Harvest index showed positive relationship with the increase in grain yield and yield components in maize. The results indicated that all the three levels of N and two levels of S increased the yield components and grain yields as well as harvest index in maize, and increased with an increase in N and S levels when compared with the control (N and S not). It is therefore, suggested that application of the highest S @ 40 kg S ha-1 and N levels @ 160 kg N ha-1 could increase maize productivity in the study area.
Keywords: Maize, nitrogen and sulfur fertilization, yield components
http://dx.doi.org/10.19045/bspab.2015.42004