Impact of Preceding Legume and Nitrogen Levels on Maize-preliminary Year Study

Abstract

An experiment on maize crop with preceding legumes and nitrogen levels were carried out at the Research Farm of Agronomy, the University of Agriculture, Peshawar during 2011-2012 using summer legumes-maize cropping pattern. The summer legumes were sown in the summer gap (60-65days) for grain, fodder and green manure purposes. Mungbean for grain and cowpea for fodder purpose and Sesbania was for green manure purpose using fallow as control. After legumes experiment each plot was split into four sub plots to accommodate four levels of N (0, 90, 120 and 150 kg ha^-1) for maize. Data were recorded on emergence, plant height, grains ear^-1 and ear weight. Soil parameters after legumes; pH, total soluble salts (TSS), electrical conductivity (EC), and calcium carbonate (CaCo₃) were not significantly affected by preceding legumes. Soil pH was higher in fallow plots while lower in plots previously cultivated with mungbean. Soil TSS, EC and CaCo₃ were higher in plots previously sown with mungbean compared with fallow plots. All the parameters under investigation were significantly affected by nitrogen levels except maize seed emergence. In legumes the plots previously sown with cowpea and mungbean significantly affected grain per ear and ear weight of maize. Taller plants were produced in plots where N was applied at the rate of 150 kg ha^-1 followed by N application of 120 kg ha^-1while control plots resulted in short stature plants. Plots fertilized with high N (150 kg ha^-1) had significantly higher ear weight which was at par with N application at the rate of 120 kg ha^-1. Higher grains per ear was recorded in plots treated with 120 kg ha^-1 N which was at par with plots fertilized with 150 kgha^-1N. Control plots resulted in fewer grains ear^-1. It is concluded from the results that plot previously sown with legume performed better than fallow and the use of legumes in cropping system will be a good strategy for sustainability in feature.