新开垦土壤上构建玉米/蚕豆-根瘤菌高效固氮模式的试验研究

o construct an efficient nitrogen-fixation crop pattern in a reclaimed soil, the greenhouse and field experiments are carried out to identify an efficient Rhizobium species and inoculation method to construct a maize/fababeanRhizobium intercropping system using newly-reclaimed low-fertility soil. Four rhizobia (NM353, CCBAU, G254 and QH258) and four inoculation methods (seed inoculation with water absorbent, seed inoculation with water, dip root at 3-leaf stage and seed obducens & inoculaiton) were employed to investigate their relative advantages with respect to grain-yield productivity, above-ground nitrogen acquisition, nodule characteristics, biological nitrogen fixation, and so on. The results show that inoculation with Rhizobium leguminosarum biovar viciae NM353 (seed inoculation via water absorbed onto the intercropping system) produces an average increase in yield of faba bean of 152.84%. While the yield of maize remained stable, the nitrogen acquired by the faba beans was the highest among the different treatments used. In addition, the number of nodules, nodule biomass, nitrogen derived from air (Ndfa), and percentage Ndfa (%Ndfa) were all greater in the newly-established system compared to non-inoculated faba beans. Especially, %Ndfa of faba bean inoculated with NM353 was 19.1% and 11.1% higher than that inoculated with CCBAU, at peak flowering and pod-filling stage, respectively, and there both showed significant differences. The differences in Ndfa of faba bean were significant between rhizobium inoculation NM353 and CCBAU at each growth stage. Relatively, the difference between NM353 inoculation and other strains was more significant, irrespectiveof %Ndfa or Ndfa. Therefore, we successfully managed to set up an efficient cropping system for nitrogen fixation. The maize/faba beanRhizobium intercropping system based on seed inoculated with Rhizobium NM353 and reclaimed low-fertility soil thereby provides a sustainable development model for the rational development and utilization of arable soil.