Evaluation of economical yield and radiation use efficiency of maize and cotton in sole and ‎intercropping systems as affected by different levels of Nitrogen

In order to study the potential of maize-cotton intercropping for improving radiation use efficiency (RUE), an experiment was conducted as a factorial arrangement based on completely randomized block design with three replications at experimental filed of Ferdowsi University of Mashhad. The experimental treatments were nitrogen in four levels (0, 50, 100 and 150 Kg N ha-1) and planting pattern in three levels (maize and cotton sole cropping and maize/cotton intercropping). LAI, dry matter and yields of maize and cotton were measured during the growing season. The results showed that economical yields of maize and cotton were significantly increased as affected by increase in N level. Economical yields of both crops in sole cropping were higher than intercropping system due to higher plant density. LAI and intercepted PAR in intercropping system were higher than sole cropping, and the traits were improved by increasing N levels. In all the N levels, LERPAR was greater than one, which represents the positive role of intercropping on radiation intercept compared to sole cropping. In general, the results showed that RUE in intercropping system was higher than sole cropping of the two species. Also, maize had higher RUE in comparison with cotton in all the experimental treatments. It seems that the intercropping system can be considered an appropriate approach for efficient use of resources.