兼具固氮、解磷功能菌株固氮特性的研究

Research on N-fixing property of bacteria with N-fixation and dissolving P function

试验研究 9株兼具固N、解P功能菌株在无N、N源充足不同P源条件和混合培养时菌株固N特性结果表明 ,供试菌株在无N培养基上均有固N活性 ,但固N量差异较大 ,菌株“N5 1”固N量最高达 5 5 .4mg/kg ,为固N量最低菌株“K10 2”的 3.1倍。在以Ca3 (PO4) 2 作P源、培养液N素供应充足时“K10 2”和“N17”菌株仍有较高固N能力 ,培养 3d后培养液全N含量增幅达 5 5 .2 % ;“N11”、“N12”和“P14 2”菌株固N量也维持在较高水平 ,全N含量增加30 %左右 ;“K16”菌株培养液全N含量略有增加 ,“N5 1”、“N13 1”和“K3”菌株则导致N的挥发损失。以磷矿粉作P源可使该过程逆转。在Ca3 (PO4) 2 P源培养基上混合培养能有效降低“N5 1”、“N13 1”和“K3”菌株单独培养时所造成的N损失。

The N-fixing property of 9 bacteria with N-fixation and dissolving P function was studied under the conditions of non-nitrogen, different P resources with sufficient nitrogen and their mixed incubation. The results show that there are different N-fixation activities under the non-nitrogen condition, however, the volume of N-fixation has more diversity. The bacteria with the highest N-fixation amount is N5-1, reaching 55.4mg/kg and 3.1 times as much as the lowest 'K10-2'. When taking Ca 3(PO 4) 2 as P resource, 'K10-2' and 'N17' still have an active N-fixing ability under sufficient nitrogen supplied, the increasing range of total nitrogen in the culture solution gets to 55.2% after 3 days incubation. The N-fixation content of 'N11', 'N12', 'P14-2' also maintain on a higher level, the total nitrogen increases by 30% or so. The total nitrogen of 'K16' in the culture solution has a little increase. 'N5-1', 'N13-1' and 'K3' result in the volatilization loss of nitrogen. These processes will be reserved when taking the ground phosphate rock as the P-resource. Compared to the single culture, the mixed incubation on Ca 3(PO 4) 2 medium can effectively decrease N-loss of 'N5-1', 'N13-1', and 'K3'.