Lima bean (Phaseolus lunatus L.) is the second most important species of the Phaseolus genus worldwide. In Brazil, it is grown primarily in the semiarid Northeast region. Although lima bean establishes symbiosis with N₂-fixing bacteria (rhizobia), there is not yet a recommended inoculant. The aim of this study was to phenotypically and genotypically characterize rhizobia strains isolated from root nodules of lima bean collected in a Northeast region, and to evaluate their efficiency in supplying N nutrition to the crop under axenic conditions and in a Humic Rhodic Hapludox with and without correction of acidity. The symbiotic efficiencies were evaluated in a greenhouse under axenic conditions and, afterward, in pots with nonautoclaved soil with and without liming. Treatments consisted of the strains under evaluation, controls without inoculation (with low or high concentration or without mineral N), and a strain efficient for the crop. In all, 66 strains were isolated from the root nodules with predominance of strains belonging to the Bradyrhizobium genus. Liming brought about increases in lima bean development as it interacted with some strains. Six strains of the Bradyrhizobium genus, belonging to groups of type strains that include B. elkanii and B. japonicum, stood out for their biotechnological potential as inoculants for lima bean, and they should be tested in the field with the aim of validating their recommendation as inoculants for that crop.

中文翻译：

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从半干旱地区收集的利马豆根瘤中分离出的根瘤菌的多样性和生物技术潜力

利马豆 ( Phaseolus lunatus L.) 是世界上菜豆属第二重要的物种。在巴西，它主要生长在半干旱的东北地区。虽然利马豆与 N ₂建立共生关系- 固定细菌（根瘤菌），目前还没有推荐的接种剂。本研究的目的是对从东北地区收集的利马豆根瘤中分离的根瘤菌菌株进行表型和基因型表征，并评估它们在无菌条件下和腐殖质红叶双歧杆菌中为作物提供 N 营养的效率。酸度的修正。在无菌条件下的温室中评估共生效率，然后在带有和不加石灰的非高压灭菌土壤的盆中进行评估。处理包括评估中的菌株、未接种的对照（具有低浓度或高浓度或不含矿物质 N）和对作物有效的菌株。总共从根瘤中分离出 66 株菌株，其中以属于慢生根瘤菌属。由于石灰与某些菌株相互作用，因此它促进了利马豆的发育。Bradyrhizobium属的6 个菌株，属于包括B. elkanii和B. japonicum在内的类型菌株，因其作为利马豆接种剂的生物技术潜力而脱颖而出，应在现场进行测试，以验证其建议作为该作物的接种剂。