Agunbiade Victor Funso, Fadiji Ayomide Emmanuel, Agbodjato Nadège Adoukè, Babalola Olubukola Oluranti
Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho 2735, South Africa.
Plants (Basel). 2024 May 8;13(10):1298. doi: 10.3390/plants13101298.
Drought is one of the main abiotic factors affecting global agricultural productivity. However, the application of bioinocula containing plant-growth-promoting rhizobacteria (PGPR) has been seen as a potential environmentally friendly technology for increasing plants' resistance to water stress. In this study, rhizobacteria strains were isolated from maize ( L.) and subjected to drought tolerance tests at varying concentrations using polyethylene glycol (PEG)-8000 and screened for plant-growth-promoting activities. From this study, 11 bacterial isolates were characterized and identified molecularly, which include A5-1, A1-2, C7_8, B8-3, A10-11, A9-10, B9-5, B15-6, B12-4, C6-7, and C1-9. All isolates were positive for indole-3-acetic acid (IAA), siderophore, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, ammonia production, nitrogen fixation, and phosphate solubilization, but negative for hydrogen cyanide production. strains A1-2 and C7_8, showing the highest drought tolerance of 0.71 and 0.77, respectively, were selected for bioinoculation, singularly and combined. An increase in the above- and below-ground biomass of the maize plants at 100, 50, and 25% water-holding capacity (WHC) was recorded. Bacterial inoculants, which showed an increase in the aerial biomass of plants subjected to moderate water deficiency by up to 89%, suggested that they can be suitable candidates to enhance drought tolerance and nutrient acquisition and mitigate the impacts of water stress on plants.
干旱是影响全球农业生产力的主要非生物因素之一。然而,应用含有促植物生长根际细菌(PGPR)的生物菌剂已被视为一种潜在的环境友好型技术,可提高植物对水分胁迫的抗性。在本研究中,从玉米中分离出根际细菌菌株,并使用聚乙二醇(PEG)-8000在不同浓度下进行耐旱性测试,并筛选其促植物生长活性。通过本研究,对11株细菌分离株进行了分子特征鉴定,包括A5-1、A1-2、C7_8、B8-3、A10-11、A9-10、B9-5、B15-6、B12-4、C6-7和C1-9。所有分离株的吲哚-3-乙酸(IAA)、铁载体、1-氨基环丙烷-1-羧酸(ACC)脱氨酶、产氨、固氮和溶磷试验均呈阳性,但氰化氢产生试验呈阴性。分别单独和组合选择耐旱性最高(分别为0.71和0.77)的菌株A1-2和C7_8进行生物接种。记录了在持水量为100%、50%和25%时玉米地上和地下生物量的增加情况。细菌接种剂使中度缺水植物的地上生物量增加了89%,这表明它们可能是增强耐旱性和养分获取以及减轻水分胁迫对植物影响的合适候选者。