Abiala Moses, Sadhukhan Ayan, Sahoo Lingaraj
Department of Biological Sciences, College of Basic and Applied Sciences, Mountain Top University, Prayer City, Ogun State, Nigeria.
Department of Biosciences and Bioengineering, Indian Institute of Technology, Guwahati, Assam, India.
Curr Microbiol. 2023 Mar 16;80(5):140. doi: 10.1007/s00284-023-03246-8.
This study aimed to isolate stress-tolerant phytobeneficial bacteria as bio-inoculants for cowpea's sustainable growth under drought and nutrient deficiency conditions. However, the application successful of phytobeneficial bacteria is subject to effective in vitro screening under different physiological conditions. We isolated several Priestia species from cowpea rhizosphere that tolerates polyethylene glycol (PEG6000)-induced drought and nutrient deficiency. Of them, C8 (Priestia filamentosa; basonym: Bacillus filamentosus), followed by C29 (Priestia aryabhattai; basonym: Bacillus aryabhattai), tolerated up to 20% PEG in a low-nutrient medium. In the presence of PEG, Priestia filamentosa and Bacillus aryabhattai exhibited optimal growth in different temperatures and pH but failed to survive at extreme temperatures of 45 °C and pH 11. Priestia filamentosa preferred L-proline and L-glutamate, while L-tryptophan and L-tyrosine were the least utilized. Interestingly, Priestia filamentosa and Bacillus aryabhattai used more complex nitrogen sources, peptone, and yeast extract, than inorganic nitrogen for growth. Most importantly, under drought and nutrient deficiency, Priestia filamentosa exhibited multiple plant growth-promoting traits and more amylase and protease production than C29. Our results indicate that Priestia filamentosa is a potential bacterium to enhance the growth of cowpea plants under stressful conditions.
本研究旨在分离耐胁迫的植物有益细菌，作为豇豆在干旱和养分缺乏条件下可持续生长的生物接种剂。然而，植物有益细菌的成功应用取决于在不同生理条件下进行有效的体外筛选。我们从豇豆根际分离出几种Priestia属细菌，它们能耐受聚乙二醇（PEG6000）诱导的干旱和养分缺乏。其中，C8（丝状Priestia菌；异名：丝状芽孢杆菌），其次是C29（阿氏Priestia菌；异名：阿氏芽孢杆菌），在低养分培养基中能耐受高达20%的PEG。在PEG存在的情况下，丝状Priestia菌和阿氏芽孢杆菌在不同温度和pH值下表现出最佳生长，但在45℃的极端温度和pH值为11时无法存活。丝状Priestia菌偏好L-脯氨酸和L-谷氨酸，而L-色氨酸和L-酪氨酸的利用率最低。有趣的是，丝状Priestia菌和阿氏芽孢杆菌在生长过程中使用比无机氮更复杂的氮源、蛋白胨和酵母提取物。最重要的是，在干旱和养分缺乏条件下，丝状Priestia菌表现出多种促进植物生长的特性，并且比C29产生更多的淀粉酶和蛋白酶。我们的结果表明，丝状Priestia菌是一种在胁迫条件下促进豇豆植株生长的潜在细菌。
