【作者】 严君；

【导师】 祖伟；

【作者基本信息】 东北农业大学 ， 作物栽培学与耕作学， 2011， 博士

【摘要】 大豆体内的氮素主要有三个来源,根瘤固氮、土壤氮和肥料氮。由于大豆依靠根瘤固定的氮远远无法满足大豆生长发育及高产的需要。同时土壤中能为大豆直接吸收利用的铵态氮和硝态氮含量不足1%,因此生产上必须施用适量的氮肥。氮肥施入到土壤中以后与土壤本身的无机氮一起统称为土壤环境无机氮,大豆对氮肥的反应实际上是大豆根系及其共生固氮系统对土壤环境无机氮含量的感知和响应。本试验采用盆栽试验方法,选用具有不同土壤环境无机氮含量的土壤,研究大豆结瘤固氮及生长发育对土壤环境无机氮含量的响应。主要研究结果如下:1)根瘤固氮对土壤环境无机氮含量的响应土壤环境无机氮含量与不同生育时期根瘤干重、数量、根瘤固氮酶活性及豆血红蛋白含量间均具有负相关关系,而不同生育时期的根瘤干重和数量间具有正相关关系。不同供氮方式不同土壤环境无机氮含量对大豆R₆期根瘤干重和数量的（或相对）抑制大小表现为:R₃期> V₂期> R₁期> R₅期>播期>持续供氮。M3处理时(334.31 mg·kg^-1),零结瘤;土壤环境无机氮含量≥M4处理(380.43 mg·kg^-1)时,产生烧苗,大豆致死。R₁期土壤环境无机氮含量达到H3处理(309.09 mg·kg^-1),零结瘤。根瘤固氮酶活性和豆血红蛋白含量间具有正相关关系。不同供氮方式不同土壤环境无机氮含量对大豆根瘤豆血红蛋白含量和固氮酶活性的（或相对）抑制表现为:R₃期> R₁期> V₂期> R₅期>持续供氮>播期。土壤环境无机氮含量≥J4处理时(290.20 mg·kg^-1),根瘤固氮酶活性和豆血红蛋白含量为零。2)大豆生长发育对土壤环境无机氮含量的响应干物质积累过程和根系生长过程均呈“S”型曲线。播期不同土壤环境无机氮含量与干物质积累总量呈正相关关系,而持续供氮方式、V₂、R₁、R₃和R₅不同土壤环境无机氮含量与干物质积累总量均呈极显著负相关关系。持续供氮和播期不同土壤环境无机氮含量处理干物质积累总量由R₆期的干物质积累量所决定;而V₂、R₁、R₃和R₅期不同土壤环境无机氮含量处理干物质积累总量由R₈期的干物质积累量所决定。不同供氮方式不同土壤环境无机氮含量处理对大豆干物质积累总量的促进大小表现为:R₅期> R₁期> R₃期>播期>持续供氮> V₂期,其中R₅期不同土壤环境无机氮含量处理的干物质积累总量高于其它不同土壤环境无机氮含量处理。不同土壤环境无机氮含量的根冠比随着生育时期的推进均呈逐渐下降的变化趋势。R₄期以前,CK2处理的根冠比显著高于其它施氮处理,R₆期以后不同土壤环境无机氮含量处理下的根冠比差异不显著。不同生育时期根长、根表面积、根体积间均具有正相关关系。持续供氮方式不同土壤环境无机氮含量与根长、根体积间均具有负相关关系。适宜的土壤环境无机氮含量有利于根长、根表面积、根平均直径、根体积的增加。播前不同土壤环境无机氮含量与根长、根表面积、根体积间均具有负相关关系,而与根平均直径呈正相关关系。3)大豆干物质积累对土壤环境无机氮含量的响应不同的土壤环境无机氮含量与大豆氮素积累总量均具有极显著负相关关系,适量的土壤环境无机氮含量有利于大豆氮素积累总量的增加。非持续供氮方式不同土壤环境无机氮含量处理的氮素积累总量均高于持续供氮处理,但随着土壤环境无机氮含量的增加氮素积累呈逐渐下降的变化趋势。4)大豆产量对土壤环境无机氮含量的响应播期不同土壤环境无机氮含量大豆产量低于持续供氮不同环境无机氮处理,而V₂期、R₁期、R₃期和R₅期不同土壤环境无机氮含量处理下大豆产量高于持续供氮不同环境无机氮处理。播期、V₂、R₁、R₃和R₅期不同土壤环境无机氮含量对产量影响的大小表现为:R₅期> R₃期> R₁期> V₂期>持续供氮>播期,以R₅期G2处理的产量最大,达13.47 g·pot^-1。更多还原

【Abstract】 The nodule nitrogen fixation, soil nitrogen and fertilizer nitrogen were the main resource of the growth in soybean. Due to the the nitrogen fixation can not satisfy the growth of soybean, so it necessary to applicate some fertilizer. However, the fertilizer can improved the soybean yield, inhibited the ability of nitrogen fixation. Actually the reaction of nitrogen on soybean was the reaction on symbiotic nitrogen-fixing system and root to soil environmental inorganic nitrogen. It means the fertilizer was put into the soil, it was dissolved and changed into the environmental nitrogen and which was together with the intrinsic environmental nitrogen affect the nitrogen fixation and growth of soybean. The content of soil environmental inorganic nitrogen derived from the sand and clay soil with the same N application rate is different. Meanwhile this is the reason for the ability of nitrogen fixation and development of soybean was different with the same N application rate. In this paper, a pot experiment was conducted to study the effects of the content of the environmental inorganic nitrogen content, which derived from different nitrogen application rate and style, on the ability of nitrogen fixation and development of soybean, and quantify their relationship. The main research results are as follows:1)Effect of soil environmental inorganic nitrogen content on nitrogen fixation of noduleIt was found that the nodule dry weight, number, nitrogenase activity and Lb content had the obviously negative related with the soil environmental inorganic nitrogen content, respectively. The nodule weight had the positive related with the nodule number in different growth stage of soybean. The nodule weight and number was lower before R2 stage of the soil environmental nitrogen content in the sowing date than the soil environmental nitrogen content derived from the continuous N supply style. However, it was higher in the R₆ stage. The nodule number and weight was inhibited by different soil environmental inorganic N derived from the uncontinuous N supply style, the trend showed: R₃ > V₂ > R₁ > R₅ > sowing. Meanwhile, the nodule number and weight was inhibited more seriously with the different environmental inorganic nitrogen content at V₂、 R₁、R₃ and R₅ stage than the different environmental inorganic nitrogen content derived from continuous nitrogen supply style and in sowing date. The nodule number and weight was inhibited with the M3 and H4 treatment, by the soil environmental inorganic content was 264.10 and 238.88 mg·kg^-1 which was named as zero-nodulation content. And≥310.22 mg·kg^-1 with the M4 treatment causing death.The nitrogenase activity were obviously related with and Lb content. The nitrogenase activity and Lb content was inhibited more seriously with different soil environmental inorganic N derived from the continuous N supply style than the different soil environmental inorganic N derived from the N supply in the sowing date. The nitrogenase activity and Lb content was inhibited by different soil environmental inorganic N derived from the uncontinuous N supply style, the trend showed: R₃ > R₁ > V₂ > R₅ > sowing. It was found that the nitrogenase activity and Lb content was inhibited with the J4 treatment, by the soil environmental inorganic content was 219.99 mg·kg^-1 which was named as zero- nitrogenase activity and Lb content content.2) Effect of the environmental nitrogen content on the development of soybeanThe process of dry matter accumulation and root development showed the same change with“S”. The dry matter accumulation had the negative related with the soil environmental inorganic content derived from the treatment with continuous nitrogen supply style, amd at V₂, R₁, R₃ and R₅ stage, and had positive related with the different soil environmental inorganic nitrogen in sowing date. The dry matter accumulation of different soil environmental inorganic N derived from the continuous N supply style and in sowing date was decided by the dry matter accumulation at R₆ stage, and the dry matter accumulation with the treatment of different soil environmental inorganic N derived from the uncontinuous N supply style was decided by the dry matter accumulation at R8 stage. The total dry matter accumulation was lower with the treatment of different soil environmental inorganic N derived from the continuous N supply style than the treatment of different soil environmental inorganic N derived from the uncontinuous N supply style, and the treatment of different soil environmental inorganic N at V₂, R₁, R₃ and R₅ stage. The dry matter accumulation was increased by different soil environmental inorganic N derived from the uncontinuous N supply style, the trend showed: R₅ > R₁ > R₃ > sowing > V₂. The dry matter accumulation was higher of the treatment at R₅ stage than the other treatment. The R/S was decreased with the growth of soybean increased. The root dry weight was lower with the treatment of N supply in sowing date than the treatment of different soil environmental inorganic N derived from the continuous N supply style. The root dry weight at R₆ stage with the treatment of different soil environmental inorganic N derived from N applicated in V₂, R₁, R₃ and R₅ stage was increased with the soil environmental inorganic N content inceased.It was found that the root length, surfarea and root volume had the obviously negative related with each other. The root length and root volume had the obviously negative related with the soil environmental inorganic nitrogen content, respectively. The optimal soil environmental inorganic nitrogen content was benefit to the increase of root length, surfarea and root volume. The root length, root surfare and root volume had the obviously negative related with the soil environmental inorganic nitrogen content, and the root average diameter had positive with the soil environmental inorganic nitrogen content.3) Effect of the environmental nitrogen content on N accumulation of soybeanThe total nitrogen accumulation had the obviously negative related with the soil environmental inorganic nitrogen content. The optimal soil environmental inorganic nitrogen content was benefit to the total nitrogen accumulation. The total nitrogen accumulation was higher with the treatment of different soil environmental inorganic N derived from uncontinuous N supply style, however, showed the decreased trend in the growth stage.4) Effect of the environmental nitrogen content on the yield of soybeanThe yield was lower with the different environmental nitrogen content in sowing date than the the different environmental nitrogen content of continuous N supply style. Meanwhile, the yield with the different environmental nitrogen content at V₂, R₁, R₃ and R₅ stage was higher than the treatment of different soil environmental inorganic N derived from continuous N supply style. The yield was increase by different soil environmental inorganic N derived from the uncontinuous N supply style, the trend showed: R₅ > R₃ > R₁ > V₂ > sowing. The yield with different soil environmental nitrogen content at the R₅ stage was higher than the other treatment. The G2 treatment was had the highest yield at 13.47 g·pot^-1 than the other treatment.更多还原