Influence of rates and methods of manganese application on yield and nutrition of wheat in a reclaimed sodic soil

Abstract

SUMMARYA field experiment was conducted at the experimental farm of the Central Soil Salinity Research Institute, Karnal, India during 1992/93 to evaluate the effects of rates and methods of manganese application on the yield and nutrition of wheat on a reclaimed and intensively cropped Mn-deficient sodic soil (pH = 8·7, exchangeable sodium percentage = 18 and DTPA-extractable Mn = 2·7 mg kg-1). There were eight treatments which consisted of a control (no Mn application), three rates of 25, 50 and 100 kg MnSO4. H2O ha-1 each either as a basal or a top-dressing at first irrigation or a foliar spray of 1·0% MnSO4.H2O at crown root initiation (CRI), tillering and jointing stages. Grain and straw yield of wheat increased significantly with increasing rates of Mn application. A foliar spray of Mn produced a significantly higher yield than 25 and 50 kg MnSO4. H2O ha-1 applied either as a basal or a top-dressing but similar to that from 100 kg MnSO4.H2O ha-1. Efficiency of Mn was higher with a foliar spray (82·6 kg grain kg-1 Mn) than with soil application (4·4–6·4 kg grain kg-1 Mn). Application of Mn increased its concentration in the crop but decreased Fe and Cu crop concentrations. Grain yield had a significant positive correlation with the Mn content of the grain (r = 0·72) and straw (r = 0·78). Grain yield was positively correlated with 1000-grain weight (r = 0·90). Recovery of applied Mn ranged from 28·1 to 33·0%.