氮肥和根瘤菌剂互作对花生氮素吸收、氮代谢及产量的影响OA北大核心CSTPCD

Unreasonable application of nitrogen fertilizer led to inhibition of biological nitrogen fixation ability.Interaction effect of nitrogen fertilizer and rhizobium agent was studied for high-efficiency production-increasing of peanut.Two peanut varieties,Nonghua 5(NH5,low nodulation)and Honghua 16(HH16,high nodulation)were used as materials.Based on outdoor pot experiments,effects of different nitrogen application rates(N0,N45,N75,N105,N135,N165)were determined,also as seed dressing with distilled water(W),and seed dressing with rhizobi-um agent(R)on the morphological indexes,nodulation characteristics,photosynthetic characteristics,nitrogen accu-mulation,enzyme activities related to nitrogen metabolism and yield of peanuts at podding stage(80 days after emer-gence),in order to investigate the interactive effect of nitrogen fertilizer and rhizobium agents on peanuts.Results in-dicated that the main stem length,branch length,net photosynthetic rate,chlorophyll content,photosynthetic relat-ed enzyme activity,nitrogen metabolism related enzyme activity and yield of peanut exhibited a trend of increasing initially,and followed by decreasing with the increase of nitrogen application rate.Nitrogen application inhibited peanut nodulation to a certain degree.Seed dressing with rhizobium agent could significantly alleviate this inhibito-ry effect.The number of root nodules of NH5 and HH16 increased by 28.4%-130.5%and 40.5%-178.3%,respec-tively,compared with distilled water seed treatment.Under the condition of seed dressing with distilled water(W),the photosynthetic enzyme activities and nitrogen metabolizing enzyme activities in peanut leaves reached their max-imum value at the nitrogen application rate of N135.Under the condition of seed dressing with rhizobium agent(R),the activities of photosynthetic enzyme and nitrogen metabolizing enzyme in leaves reached their maximum at N105.Compared with W,the yields of NH5 and HH16 were increased by 1.2%-8.3%and 7.5%-11.0%at each nitrogen application rate,respectively.The yields of NH5 and HH16 per plant reached the maximum under N105-R treat-ment.In conclusion,the combination of nitrogen fertilizer and seed dressing with rhizobium agent could significant-ly improve peanut nodulation and reduce the dependence on nitrogen fertilizer.Therefore,suitable nitrogen fertilizer combined with rhizobium agent could improve nitrogen fixation ability while maintaining a high yield,which might be a green and effective way to increase peanut output.