Promiscuous soybeans are grain legumes that nodulate with diverse strains of indigenous Bradyrhizobium and play a significant role in biological nitrogen fixation through symbiosis. However, experiments on the potential use of promiscuous soybean varieties have recorded very low nodulation and poor nitrogen fixation probably due to ineffective native Bradyrhizobium isolates. Experiments were designed to investigate symbiotic nitrogen fixation of two promiscuous soybean varieties (SB8 and SB126) with indigenous Bradyrhizobium isolates in contrasting agroclimatic zones through greenhouse and field experiments. Inoculation of soybeans in the greenhouse had a significant (p < 0.001) effect on shoot and nodule dry weight. The best performing indigenous isolates RI9 and RI4 from the greenhouse study outperformed the commercial inoculant (Biofix) in symbiotic effectiveness with 119.17%, 142.35% and 101.01%, respectively. Inoculation in the field experiments showed a significant (p < 0.0001) increase in shoot dry weight and grain yield of promiscuous soybean. Agroclimatic zones showed significant (p < 0.0001) variability in above ground biomass of soybean due to inoculation. Despite the apparent promiscuity of the soybean varieties used, the response in nodulation suggests the cultivars grown under contrasting agroclimatic zones have a preference to specific Bradyrhizobium isolates.

中文翻译：

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不同农业气候条件下混杂大豆对当地和商业化慢生根瘤菌接种的差异反应

混杂大豆是豆科植物，与不同的本地慢生根瘤菌菌株结瘤，并通过共生在生物固氮中发挥重要作用。然而，关于混杂大豆品种的潜在用途的实验记录了极低的结瘤和较差的固氮作用，这可能是由于无效的天然慢生根瘤菌分离物所致。实验旨在通过温室和田间试验研究两种混杂大豆品种（SB8 和 SB126）与本土慢生根瘤菌分离株在对比农业气候区的共生固氮作用。在温室中接种大豆对芽和根瘤干重有显着影响（p < 0.001）。温室研究中表现最好的本土分离株 RI9 和 RI4 在共生有效性方面优于商业接种剂 (Biofix)，分别为 119.17%、142.35% 和 101.01%。田间试验中的接种表明混杂大豆的地上部干重和籽粒产量显着增加（p < 0.0001）。由于接种，农业气候区显示出大豆地上生物量的显着（p < 0.0001）变异性。尽管使用的大豆品种明显混杂，但结瘤反应表明在对比农业气候带下生长的品种偏爱特定的慢生根瘤菌分离株。0001) 增加混杂大豆的芽干重和籽粒产量。由于接种，农业气候区显示出大豆地上生物量的显着（p < 0.0001）变异性。尽管使用的大豆品种明显混杂，但结瘤反应表明在对比农业气候带下生长的品种偏爱特定的慢生根瘤菌分离株。0001) 增加混杂大豆的芽干重和籽粒产量。由于接种，农业气候区显示出大豆地上生物量的显着（p < 0.0001）变异性。尽管使用的大豆品种明显混杂，但结瘤反应表明在对比农业气候带下生长的品种偏爱特定的慢生根瘤菌分离株。