Fortification of iron in finger millet (Eleusine coracana L.): Impact of conventional and nano NPK fertilizers combined with inorganic and organic iron sources in an acidic sandy loam soil
*1A. Mathesh, 2K. Arivazhagan, 3P. Senthilvalavan and 4S. Natarajan
1,2,3Department of Soil Science and Agricultural Chemistry, 4Department of Agronomy, Faculty of Agriculture, Annamalai University, Annamalai Nagar, Tamil Nadu-608002 (India) Email: arivuselvi@rediffmail.com, senkavin@gmail.com Email: sno1766@annamalaiuniversity.in *1Corresponding author email: mathesh.agri@gmail.com
ABSTRACT
The purpose of the present work was to assess the effect of combined application of conventional and nano NPK fertilizer and different iron (Fe) sources on yield and Fe uptake towards iron fortification of finger millet (Eleusine coracana L.). The experiment was carried out in a net house using factorial completely randomized design (FCRD). The factors consist of different Fe sources (Iron enriched biochar, iron enriched farmyard manure & ferrous sulphate), and different levels (75%, 100% &125 %) of conventional and nano NPK fertilizers application and replicated thrice. Results of the net house experiment revealed that the application of iron enriched biochar (FeEBC) with 125% of Nano NPK recorded higher grain (14.5 g pot-1) and straw (36.7 g pot-1) yield, Fe content (45.6 & 58.1 mg kg-1) and uptake (1.78& 2.30mg pot-1) in grain and straw, respectively. However, statistically similar results obtained by the application of Fe enriched biochar with 100% of Nano NPK on grain (13.6 g pot-1) and straw (35.6 g pot-1) yield, Fe content in grain (45.5 mg kg-1) and straw (58.6mg kg-1) and Fe uptake in grain (1.73mg pot-1) and straw (2.28 mg pot-1), respectively. So, considering the input reduction and higher net yield, nutrient content, and uptake; the application of 100% Nano NPK with Fe enriched biochar (FeEBC) can be a significant and suitable form and proportion of nutrient source for Fe fortification of finger millet grown in acidic soil conditions. From this study we found that application of nano NPK fertilizer plus FeEBC can significantly fortify the iron content in finger millet grain up to43.92 % over combined application of recommended dose of NPK conventional fertilizers and FeSO4 to finger millet.