【摘要】 以缺铁的石灰性紫色土为供试土壤进行盆栽实验,选用三株慢生型花生根瘤菌Spr3 5、Spr3 7、Spr4 5及gusA和celB标记的菌株gusA3 5、gusA3 7、gusA4 5、celB3 5、celB3 7、celB4 5接种天府9号花生。通过标记根瘤菌形成的根瘤能与检测试剂产生颜色反应的特征,检测施铁肥及施不同浓度的铁肥对花生 根瘤菌有效性和竞争性的影响。结果发现:缺铁的石灰性紫色土上单施铁肥、单接种根瘤菌、接种根瘤菌配施铁肥均能促进花生与根瘤菌的共生固氮效应和竞争结瘤能力,但接种根瘤菌配施铁肥的效果最好,单接种根瘤菌的效果次之,单施铁肥的效果差。喷施0 .2 %硫酸亚铁溶液的效果比0 .3%的好。植株全氮含量和叶绿素含量都是指示共生固氮效应的重要指标,与花生产量间存在极显著的相关性,相关系数分别为0 .76 3和0 .795。gusA和celB两种标记方法检测的结果基本一致,两种标记根瘤菌的平均占瘤率分别为79.6 4 %、75 .6 2 %、74 .4 1%。供试菌株中Spr4 5的有效性和竞争性最强,Spr3 7次之,Spr3 5最差更多还原

【Abstract】 In this research, calcareous purple soil deficient in Fe was used for pot experiment. Three strains of Bradyrhizobium Spr3 5, Spr3 7, Spr4 5 and gusA and celB labeled strains gusA3 5, gusA3 7, gusA4 5, celB 3 5, celB3 7, celB 4 5 were selected inoculate TianFu 9 peanut. Root nodule formed by gene marker strains would have color reaction with the test reagent. This characteristic can be used to detect effect of Fe fertilization and its application rate on effectiveness and competitiveness of the peanut Bradyrhizobium symbiosis. Results show that in calcareous purple soil deficient in available Fe, spraying of FeSO 4·7H 2O solution, inoculation of Bradyrhizobium or combination of the two could all promote symbiotic nitrogen fixtion and competitive ability of peanut Bradyrhizobium in nodulation, but the effect was the best with the combination, followed by inoculation and then Fe application. The effect of spraying 0.2% FeSO 4·7H 2O solution was much better than that of spraying 0.3% FeSO 4·7H 2O solution. Plant total nitrogen content and total chlorophyll content, which are both important indices of symbiotic nitrogen fixation, showed extremely significant correlations with peanut yields, with correlation coefficient being 0.763 and 0.795, respectively. Results of the test with either gusA or celB labeled strains were almost the same. The nodulation rate of the three labeled Bradyrhizobium strains, Spr3 7, Spr4 5 and Spr3 5 was averaged to be 79.46%, 75.62% and 74.41%, respectively. In terms of effectiveness and competitiveness, Strain Spr4 5 took the lead and was followed by Spr3 7 and Sp3 5 in the end.更多还原