Intercropping of Grain and Fodder Maize Crops under Different Nitrogen Levels and Cutting Dates
Ahmed M. Shaalan; Hassan E. Khalil; Ali I. Nawar and Mohamed M. El-salamouni
Two field experiments were conducted in 2013 and 2014 summer seasons, at the Experimental Research Station, Alexandria University, Egypt, to investigate the response of grain maize and fodder maize crops grown in associations to three N levels; i.e, 252 (N1), 288 (N2) and 324 (N3) kg N/ha and three cutting dates; i.e., C1= (45), C2= (60) and C3= (75) days after sowing (DAS). The most important results are summarized as follows: 1) The two studied factors significantly affected plant height, ear leaf area, ear weight, 100-grain weight, grain yield and harvest index for grain maize, as well as green fodder yield/ha and percent of dry matter in fresh fodder in both seasons. 2) Each crop gave the highest and lowest values for its characters when they received, respectively, N3 and N1 levels, as well as at 75 and 45 DAS periods of association. 3) The highest NUE of the intercrops to that of pure maize (RNUE) was obtained with the highest N level over the two seasons. 4) The highest values of dry matter equivalent ratio (DMER) amounted to 1.23 and 1.26 (for N3), while, the lowest ones were 0.99 and 1.00 (for N1 level), corresponding to 1.25 and 1.29 for (C3), as well as, 1.09 and 1.10 for (C1) in 2013 and 2014 seasons, respectively. Keywords: Intercropping, grain maize, fodder maize, nitrogen levels and cutting dates.