Food Security and Safety Niche, Faculty of Natural and Agricultural Science, North-West University, Private Mail Bag X2046, Mmabatho, 2735, South Africa.
Curr Microbiol. 2021 Apr;78(4):1615-1627. doi: 10.1007/s00284-021-02432-w. Epub 2021 Mar 9.
Food insecurity is a serious threat due to the increasing human population particularly in developing countries and may be minimized by the use of microbial inoculants. Also, the problems of excessive use of chemical fertilizers including the fact that most of the fertilizers are relatively non-affordable and that they also contaminate underground and surface water, which can increase the risk of blue baby syndrome in infants and stomach cancer in adults. There is therefore the need to harness a more cost-effective, eco-friendly and beneficial biological agents to improve crops productivity especially under drought conditions. Thus, in this study, the ability of rhizobia species and arbuscular mycorrhizal fungi (AMF) to enhance soybean tolerance to drought stress under water regimens of 100, 70 and 40% field capacity (FC) was investigated. It was observed that co-inoculation of soybean with Rhizobium spp. (R1+R3) as well as with Rhizobium spp. and mycorrhizal consortium (R1+R3MY) had significant impacts (P < 0.05) on soybean leaf relative water content and electrolyte leakage, respectively. The levels of proline increased mainly in microbially amended soybean exposed to drought stress. Plants inoculated with R1+R3MY showed the highest number of spore and % mycorrhization in all the water regimes. At 40% FC, R1+R3MY treatment was found to promote soybean growth compared to the non-inoculated plants. Similarly, at 40% FC, R1+R3MY inoculum had the greatest impacts on soybean pod number, seed number, seed fresh weight, highest seed number per pod and seed dry weight while at 70% water stress, significant impacts of R1MY inoculation were observed on pod number, pod fresh weight and seed dry weight. These results revealed that co-inoculation of rhizobia and mycorrhizal fungi can be harnessed biotechnologically to proffer solution to food insecurity.
粮食不安全是一个严重的威胁，特别是在发展中国家，由于人口不断增加，这一问题可能会加剧，可以通过使用微生物接种剂来尽量减少这种威胁。此外，化肥的过度使用也带来了一些问题，包括大多数化肥相对负担不起，而且它们还会污染地下水和地表水，这会增加婴儿患蓝婴症和成年人患胃癌的风险。因此，需要利用更具成本效益、对环境友好和有益的生物制剂来提高作物的生产力，特别是在干旱条件下。因此，在这项研究中，研究了根瘤菌和丛枝菌根真菌（AMF）在 100%、70%和 40%田间持水量（FC）水培条件下增强大豆耐旱性的能力。结果表明，大豆与根瘤菌（R1+R3）以及根瘤菌和菌根共生体（R1+R3MY）共接种对大豆叶片相对含水量和电解质渗出率有显著影响（P < 0.05）。在受到干旱胁迫的微生物处理的大豆中，脯氨酸水平主要增加。在所有水培条件下，接种 R1+R3MY 的植物的孢子数和%菌根化率最高。在 40% FC 时，与未接种的植物相比，R1+R3MY 处理促进了大豆的生长。同样，在 40% FC 时，R1+R3MY 接种对大豆荚数、种子数、种子鲜重、每荚种子数和种子干重的影响最大，而在 70%水分胁迫下，R1MY 接种对荚数、荚鲜重和种子干重有显著影响。这些结果表明，根瘤菌和菌根真菌的共接种可以被生物技术利用，为解决粮食不安全问题提供解决方案。
