Initial effects of nitrogen rate on nodulation of peanut in sole and intercropping system in semi-humid area in Liaoning

The maize/peanut intercropping is an important cereal/legume intercropping system in Liaoning. This intercropping system can reduce wind erosion, increase yield and resource use efficiency. To clarify the effects of nitrogen rate on nodulation characteristic of peanut in sole and intercropping system in semi-humid area, a micro-plot experiment was conducted at the Drought-resistant Cultivation Simulation Test Site, Liaoning, Northeast China. Including two cropping system (sole peanut and maize/peanut intercropping) and seven N rates (0, 50, 75, 100, 150, 200 and 300 kg/ha) based on the cropping pattern. The results showed that maize/peanut intercropping have the potential to enhance the nodulation of peanut and there was alleviatory effect on the inhibitory effect of N fertilization on the nodulation of peanut when intercropped with maize in earlier stage in semi-humid area. These advantages can be due to the enhancement of nodule number or facilitation of the single nodule development, or both of them by intercropping with maize. There was interaction between cropping system and the N input. More tests should be done in different climate conditions, agronomics, growing stages, and N rates to clarify the potential of peanut nodulation forming and to maximize the biological N fixation of peanut in intercropping system.