Interaction between different nitrogen fertilizer levels and maize-bean intercropping patterns

Abstract

In order to investigate the effects of different maize-bean intercropping patterns, and of nitrogen fertilizers on morphological and yield related traits, a factorial study based on Randomized Complete Block Design (RCBD) was performed during the 2010 and 2011 growing seasons in a research filed of Shiraz University, Iran. The first factor of the study was seven different ratios of Maize-Bean intercropping system (Maize sole cropping, Bean sole cropping, and intercropping of maize/bean at the ratios of 1/3, 1/1, 2/3, 3/2 and 3/1) and the second factor was three nitrogen (N) fertilizer application levels (0, 100 and 200 kg N/ha). Results showed that with respect to increasing the levels of N fertilizer, the yield of bean sole cropping decreased but the yield of maize sole cropping increased. On the other hand, in intercropping systems with N fertilizer application, the yield of both crops increased. Results of total land equivalent ratio (LER) for both crops showed that the highest LER value under both 100 and 200 kg N/ha application was that of M1B1 (1 seed of maize after 1 seed of bean, consecutively, on a row with same distance). Under no N fertilizer application the highest LER value was that of M2B3 (2 seeds of maize after 3 seeds of bean, consecutively, on a row with same distance). Overall, it can be concluded that M1B1 is the best intercropping pattern in maize-bean intercropping systems and that the application of N fertilizer can be effective within practical settings of intercropping agriculture, resulting in higher yields.