Quantitative and Qualitative Traits of Sweet Corn As Influenced by Delayed Cropping, Biofertilizers, and Nitrogen

In order to investigate the effect of sowing date, biofertilizers, and nitrogen levels on the traits of sweet corn, an experiment was conducted for two cultivation years in Takestan (Iran). Experimental treatments consisted of sowing date at two levels d(1): usual sowing date (June 4) and d(2): delayed sowing date (July 5); nitrogen fertilizer at two levels n(1): recommended amount of nitrogen (300 kg ha(-1)) and n(2): 20% lower than the recommended amount (240 kg ha(-1)); and biofertilizer at four levels b(1): no bacteria (control), b(2): bio-superphosphate, b(3): azotobacter + azospirillum + pseudomonas, and b(4): azotobacter + bio-superphosphate. The simple effect of sowing date, nitrogen, and biofertilizer, and the interaction of nitrog x biofertilizer on seed yield were significant. The sowing date of June 4 showed an increase of about 6% in seed yield compared to delayed sowing date (July 5). The b(3) treatment had the highest seed yield and seed yield components under conditions of nitrogen of 300 kg ha(-1). At 240 kg ha(-1) nitrogen treatments, the b(3) and b(4) treatments had the highest seed yield, significantly higher than non-application of fertilizer (even at 300 kg ha(-1)). The results of this study revealed that the use of biofertilizers could generate higher yields and even compensate for a 20% reduction in nitrogen use.