Vermicompost and Azotobacter as an ecological pathway to decrease chemical fertilizers in the maize, Zea mays

Abstract

Iran is a major importer of maize in the world. Maize is one of the most important crops in the western Iran. Maize production in this region has two major problems: water shortage and low percentage of organic matter in soil. In this research, effects of vermicompost and Azotobacter as a boifertilizers and chemical fertilizers levels on yield and Some traits of leaves of Maize under normal and defi cit irrigation was investigated in two years (2014 and 2015). Results showed that grain yield, Leaf Area Index, leaf chlorophyll contents, the normalized difference vegetation index (NDVI) and Leaf relative water content (RWC) were decreased by defi cient irrigation. Use of Azotobacter and vermicompost signifi cantly increased these traits in normal and defi cit irrigation. Results also showed that using 6 ton/ha of vermicompost and Azotobacter in soil, 50% of the corn fertilizer supplied. The results showed that combined use of biofertilizers with chemical fertilizers increased the yield and other traits. Therefore the uses of biological fertilizers signifi cantly reduce the consumption of chemical fertilizers and reduce the adverse environmental effects. So biofertilizers could be considered as a suitable substitute for chemical fertilizer in organic agricultural systems. On the other hand from this experiment, application of vermicompost in combination with chemical fertilizers showed better performance than only chemical fertilizers, even in 100% recommendation based on soil test treatments. As a general conclusion these results suggest that integrating organic sources with 50% of recommended NPK fertilizers are appropriate for sustainable crop production in normal and defi cient irrigation.