Evaluation of yield and some physiological traits of forage corn affected by chemical and biological nitrogen fertilizers intercropped with sweet basil

In order to evaluate yield and some physiological traits of forage corn under nitrogen fertilizers (biological, chemical and integrated) in additive intercropping with basil a field experiment was carried out in the Experimental Farm of Faculty of Agriculture, Lorestan University during 2014-2015 growing seasons. Treatments were arranged in a factorial experiment based on randomized complete blocks design with three replications. Experimental treatments were 100% chemical fertilizer (N), bio-fertilizer (nitroxin), integration of bio-fertilizer + 50% chemical fertilizer and control in different intercropping systems consisted of sole cropping corn and the additive intercropping of corn + 25% sweet basil, corn + 50% sweet basil, corn + 75% sweet basil and corn + 100% sweet basil. The results showed that integration of bio-fertilizer + 50% chemical fertilizer had the highest number of green leaves per plant (11.72) and leaf area index (LAI) (3.75) and there was no significant difference between this treatment and using 100% chemical fertilizer (N) in plant height, stem dry weight, chlorophyll a, chlorophyll b and carotenoids contents. Among different intercropping systems the highest plant height (179.25 cm), number of green leaves per plant (11.4), leaf dry weight (5.64 ton*ha-1), ear dry weight (7.19 ton*ha-1), stem dry weight (6.11 ton*ha-1), total dry weight (19.22 ton*ha-1), chlorophyll a (0.62 mg*g-1 FW), chlorophyll b (0.42 mg*g-1 FW), and total chlorophyll (1.04 mg*g-1 FW) were obtained from sole cropping pattern. However, sole cropping pattern in terms of mentioned traits except for number of green leaves per plant, ear dry weight and total dry weight had no significant difference with corn + 25% sweet basil and corn + 50% sweet basil treatments The results showed that integration of bio-fertilizer + 50% chemical fertilizer could be considered as an approach to reduce the consumption of chemical fertilizers for sustainable agriculture