Forage yield and yield component traits of Zea maysZ.mexicana hybrid responses to planting density and nitrogen application

The effects of planting density and nitrogen application on the forage yield, yield component traits of Zea maysZ.mexicana hybrid were studied using a split plot experiment with two factors. The results showed that there were significant responses of yield and yield component traits of Z.maysZ.mexicana hybrid to planting density and nitrogen application, and the forage yield had changed with planting density and nitrogen application enrichment. The forage yield was negatively associated with green leaves, leaf length and leaf area, positively associated with density, nitrogen application, main stem perimeter, tillers, leaf broad and single plant fresh yield and very significantly positively associated with grass length. The single plant fresh yield was highly significantly associated with planting density, grass length, main stem perimeter, tillers and leaf broad and leaf area. Meanwhile, the direct actions of planting density (P0.05), single plant fresh yield (P0.05), grass length (P0.05) on forage fresh yield were significant at levels of 0.05, 0.01, 0.1, respectively. These results suggested that the planting density, single plant fresh yield and grass length were important characters for improving forage yield. The fresh forage yield of Z.maysZ.mexicana reached the highest at 59 444.74 kgha-1 with the planting density and nitrogen application of 40 000 plantha-1 and 450 kgha-1, respectively; meanwhile, the maximum dry forage yield reached the highest at 12 374.39 kgha-1 when the planting density and nitrogen application of 40 000 plantha-1 and 600 kgha-1, respectively. In conclusion, planting at 40 000 plants per hectare and applying 450 kg nitrogen per hectare were best management practices.