不同花生品种氮素利用特征相关指标研究

为探讨不同花生品种氮素利用特点,采用¹⁵N示踪技术研究了19个花生品种氮素积累与若干指标的差异性及其与产量的关系。结果表明,不同品种在氮素含量与积累量、氮素荚果生产效率、氮素生物效率、氮肥利用率及氮肥偏生产力等指标均存在显著差异,品种间变异系数为6.2%~32.0%。花生不同器官氮积累量与其干物质积累量均呈极显著正相关,相关系数为0.801 1~0.920 8,而与氮含量相关性不明显;收获指数高有利于氮素荚果生产效率的提高,而增加营养体和总生物产量有利于提升氮素生物效率;总生物产量及其向生殖体的分配比例对氮肥利用率和氮肥偏生产力有很大影响;土壤氮和根瘤固氮是花生主要氮源,供氮比例平均值分别为46.4%和40.7%,生产上应注意充分挖掘其供氮潜力。综上可知,高产花生植株需要有足够的总生物产量和氮积累,并能够将其较多地分配到生殖体;选育产量和氮素或氮肥效率同时高的品种是可能的。本研究结果为花生氮高效品种筛选、培育及节氮栽培提供了理论依据。

Study on Related Indexes of Nitrogen Utilization Characteristics for Different Peanut Varieties

In order to explore nitrogen (N) utilization characteristics for different peanut varieties, changes in some related indexes of N accumulation and utilization of 19 peanut varieties and their relationship with yield were investigated by using¹⁵N tracer technique. Results showed that: Significant differences were observed in the indexes of the N content and accumulation, N pod production efficiency, N bio-efficiency, N fertilizer utilization rate, N fertilizer partial productivity among these 19 peanut varieties. The coefficient variations (CV) for different varieties ranged from 6.2% to 32.0%; N accumulation significantly positively correlated with dry matter accumulation in different organs of peanut, and the correlation coefficient varied from 0.801 1 to 0.9208, whereas no significant correlation was found with N content. The high harvest index was beneficial to increase the N pod production efficiency, while the increases of vegetative and total biological yield were beneficial to enhance N bio-efficiency. Total biomass and its allocation rate to the reproductive body exerted large impacts on N use efficiency and N fertilizer partial productivity. Soil N and nodule fixation were the main N sources of peanut, while the average N supplying proportions from soil and nodule fixation were 46.4% and 40.7%, respectively. Therefore, more attentions should be paid in exploiting N supply potential from soil and nodule fixation in agricultural production. For high-yield peanut plants, the sufficient total biomass and N accumulation were necessary, and also the high allocation rate to the reproductive body. It was possible to select and breed the peanut varieties with both high yield and high N element (or fertilizer) efficiency. This study provides theoretical basis for peanut variety selection and breeding of high N efficiency, and N-saving cultivation technology.