Pigeon pea ( Cajanus cajan (L.) Millspaugh) is among the top ten legumes grown globally not only having high tolerance to environmental stresses along, but also has the high biomass and productivity with optimal nutritional profiles. In the present study, 55 isolates of rhizobia were identified from 22 nodule samples of pigeon pea collected from semi-arid regions of India on the basis of morphological, biochemical, plant growth promoting activities and their ability to tolerate the stress conditions viz . pH, salt, temperature and drought stress. Amongst all the 55 isolates, 37 isolates showed effective nodulation under in vitro conditions in pigeon pea. Further, five isolates having multiple PGP activities and high in vitro symbiotic efficiency were subjected to 16S rRNA sequencing and confirmed their identities as Rhizobium, Mesorhizobium , Sinorhizobium sp. Further these 37 isolates were characterized at molecular level using ARDRA and revealed significant molecular diversity. Based on UPGMA clustering analysis, these isolates showed significant molecular diversity. The high degree of molecular diversity is due to mixed cropping of legumes in the region. The assessment of genetic diversity and molecular characterization of novel strains is a very important tool for the replacement of ineffective rhizobial strains with the efficient strains for the improvement in the nodulation and pigeon pea quality. The pigeon pea isolates with multiple PGPR activities could be further used for commercial production.

中文翻译：

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从印度半干旱地区分离的木豆根瘤菌的生化、功能和分子特征

豌豆 ( Cajanus cajan (L.) Millspaugh) 是全球种植的十大豆科植物之一，不仅对环境压力具有高耐受性，而且还具有高生物量和生产力以及最佳营养状况。在本研究中，根据形态、生化、植物生长促进活性及其耐受胁迫条件的能力，从印度半干旱地区收集的 22 份木豆根瘤样本中鉴定出 55 株根瘤菌。pH、盐分、温度和干旱胁迫。在所有 55 个分离株中，37 个分离株在体外条件下在木豆中显示出有效的结瘤。此外，对具有多种 PGP 活性和体外共生效率高的 5 个分离株进行了 16S rRNA 测序，并确认了它们的身份为根瘤菌、中生根瘤菌、中华根瘤菌属 此外，使用 ARDRA 在分子水平上对这 37 个分离株进行了表征，并揭示了显着的分子多样性。基于 UPGMA 聚类分析，这些分离株显示出显着的分子多样性。高度的分子多样性是由于该地区豆类的混合种植。新菌株的遗传多样性评估和分子表征是用有效菌株替代无效根瘤菌菌株以改善根瘤菌和木豆品质的非常重要的工具。具有多种PGPR活性的木豆分离株可进一步用于商业化生产。这些分离株显示出显着的分子多样性。高度的分子多样性是由于该地区豆类的混合种植。新菌株的遗传多样性评估和分子表征是用有效菌株替代无效根瘤菌菌株以改善根瘤菌和木豆品质的非常重要的工具。具有多种PGPR活性的木豆分离株可进一步用于商业化生产。这些分离株显示出显着的分子多样性。高度的分子多样性是由于该地区豆类的混合种植。新菌株的遗传多样性评估和分子表征是用有效菌株替代无效根瘤菌菌株以改善根瘤菌和木豆品质的非常重要的工具。具有多种PGPR活性的木豆分离株可进一步用于商业化生产。新菌株的遗传多样性评估和分子表征是用有效菌株替代无效根瘤菌菌株以改善根瘤菌和木豆品质的非常重要的工具。具有多种PGPR活性的木豆分离株可进一步用于商业化生产。新菌株的遗传多样性评估和分子表征是用有效菌株替代无效根瘤菌菌株以改善根瘤菌和木豆品质的非常重要的工具。具有多种PGPR活性的木豆分离株可进一步用于商业化生产。