Augmenting yield and urea-nitrogen utilization efficiency in wheat through use of natural essential oils and dicyandiamide-coated urea in light-textured soils of central Uttar Pradesh

Abstract

A field study was conducted to compare the efficiency of Dicyandiamide (DCD)-coated urea with some natural essential oil and their derivatives viz. Mentha spicata oil, dementholized oil (DMO) and terpenes coated urea on wheat (Triticum aestivum L.) yield, nitrogen (N) uptake, and apparent N recovery on a sandy loam soil of Central Uttar Pradesh, India, where excessive loss of N due to NO3 leaching is a serious problem due to its light texture. Significant increase in grain and straw yield, N uptake, and apparent N recovery was observed on application of these nitrification inhibitors. However, their performance varied with the percentage used: it was higher with the higher level of application. All the three natural coating materials retarded nitrification significantly, throughout the growth period of wheat as compared to DCD coated urea as well as uncoated urea treated soil. Apparent N recovery by wheat with the application of these materials at 0.50% (v/w) level of coating on urea were 29.61%, 27.27%, and 22.73% with DMO, M. spicata oil and terpenes, respectively. Corresponding values at 1.00% (v/w) level of coating were 47.01%, 38.68%, 23.24%, respectively. With DCD coated urea (at 1.00% level of coating, w/w basis) it was 33.13%, while the corresponding value with uncoated urea was 22.78%. Economic analyses were done for the use of these natural coating materials for wheat cultivation. Benefits obtained from the use of DMO, M. spicata oil and terpenes at 0.50% level of coating were Rs. 5,210 ha−1, Rs. 1,400 ha−1, and Rs. 450 ha−1, respectively. While at 1.00% level of coating, corresponding profits were Rs. 9,040 ha−1, Rs. 4,570 ha−1, and Rs. 575 ha−1, respectively. Benefit obtained from the use of DCD at 1.00% level of coating was Rs. 1,005 ha−1.